Olympic weightlifting

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Olympic weightlifting (more correctly referred to as “weightlifting”) is a sport contested at the summer Olympic games. The sport involves two overhead barbell lifts called the snatch, and the clean and jerk.

Olympic weightlifters have a higher bone mineral density, less fat mass, and more muscle mass than normal, healthy control subjects. The distribution of the extra muscle mass differs from that in other strength and power sports.

Greater bodyweight, lower body fat percentage, greater type IIA muscle fiber proportion, and greater force producing ability per unit muscle cross-sectional area are all associated with superior Olympic weightlifting ability among Olympic weightlifters.

Stronger athletes are more successful than weaker athletes in Olympic weightlifting. Performance is strongly associated with both maximum isometric mid-thigh pull force and 1RM back squat. The snatch appears to be determined by leg strength but the jerk may be determined by both leg and back strength.

Olympic weightlifting training improves snatch and clean and jerk performance, lower body strength (as measured by 1RM squat and isometric force), lower body power output, short distance sprint running ability, vertical jump height, and maximum aerobic capacity (as measured by VO2-max). 

Olympic weightlifting training seems to be superior to resistance training but not plyometrics for increasing vertical jump height but whether it is superior to other types of training for any other measure (including lower body power output) is currently unclear. It can produce substantial improvements in body composition, by increasing lean body mass, as well as reducing body fat percentage.

Long-term Olympic weightlifting training seems to increase serum testosterone levels. Temporary periods of high volume Olympic weightlifting training reduce serum testosterone and serum testosterone-to-cortisol ratio, which return to normal during lower volume training. The optimal volume of Olympic weightlifting training for sport or performance enhancements is unclear.

Although the Olympic lifts are frequently described as good exercises for developing power output, they produce similar power output to sub-maximal power lifts and substantially less power output than vertical jumps.

The Olympic lifts or weightlifting derivatives may be able to produce a post-activation (PAP) effect on subsequent vertical jump height, although this may be affected by the type of exercise variation used. 

Maximum barbell vertical displacement prior to the catch in the snatch lift decreases with increasing load, is greater in males than in females, but smaller in more skilled athletes than in less skilled athletes.

In the snatch lift, the bar generally moves horizontally toward the athlete in the first pull, away in the second pull, and back again in the catch phase. The prevalence of different patterns used by lifters is unclear, and it is unknown whether one pattern is optimal. Patterns may be affected by both the load used and anthropometry.

The snatch lift has two pull phases, with the first being longer than the second. Heavier athletes and heavier loads involve a larger proportion of total lift time in the first pull. The second pull involves greater power outputs than the first pull. In the first pull, knee extension angular velocity is greatest, while in the second pull, hip extension velocity is greatest.

Hip extension net joint moments are very large in the snatch lift, with heavyweight lifters achieving 660Nm. In comparison, knee extension moments appear to be much smaller. This underscores the importance of the hip extensors for Olympic weightlifting success.

In the clean, the barbell moves horizontally toward the athlete during the first pull, away from the athlete in the second pull, and back toward the athlete in the catch phase. Superior Olympic weightlifting ability in the clean does not automatically lead to greater consistency in movement patterns.

Ground reaction forces and power outputs are greatest in the second pull phase of the clean. Transverse abdominis EMG amplitude is greatest when the barbell is at shoulder level, while erector spinae EMG amplitude and intra-abdominal pressure (IAP) are greatest when the barbell is at mid-shin level.

Although low back joint compressive and shear forces in the clean performed by elite Olympic weightlifters are high (around 8,600N and 1,200N, respectively), they are not as high as in the deadlift performed by elite powerlifters of similar bodyweight (around 14,500N and 1,700N, respectively).

The jerk is a much more knee-dominant movement than the vertical jump or jump landing, probably because the trunk is restricted from moving during this movement as a result of maintaining the barbell overhead. Training the jerk may require improving knee extension strength, and the jerk may transfer best to movements requiring substantial net knee joint moments.

A key question regarding Olympic weightlifting training is whether the apparent risks outweigh the potential benefits (called the risk-reward ratio). The answer to this question may vary according to the population (Olympic weightlifters, adult athletes, youth athletes, and general population).

As a sport, Olympic weightlifting appears to display a similar risk of injury to other strength sports, such as powerlifting and strongman. Injury incidence in elite Olympic weightlifters during training is around 2.4 – 3.3 injuries per 1,000 hours. Injury prevalence in the competition period is higher, at around 17 – 18% of athletes.

The most commonly-injured parts of the body in Olympic weightlifting are not entirely clear. The low back and knee are probably most frequently injured locations, followed by the shoulder. Olympic weightlifters may also be at a higher risk of developing long-term overuse joint damage at the low back (including spondylolysis) and knee.

Weightlifting derivatives are exercises that are produced when technique modifications are made to the two main lifts (the snatch, and the clean and jerk). They are less technically difficult to perform and are generally performed with lighter absolute loads.

Training with weightlifting derivatives improves weightlifting derivative performance, lower body strength (as measured by 1RM squat and force production), peak power output, and vertical jump height. Frequent expert demonstration may enhance technique improvements and technique improvements are related to gains in peak power output.

Whether weightlifting derivatives are superior to other types of training for any outcome is currently unclear, although preliminary results suggest that they may be better than conventional resistance training for improving vertical jump height, just like Olympic weightlifting.

In weightlifting derivatives, peak force occurs with the heaviest training loads and peak velocity occurs with the lightest training loads. The load at which peak power is achieved differs by exercise variation and is greatest with the heaviest loads in the power clean, moderate-to-heavy loads in the hang power clean and push press, moderate-to-light loads in the high pull, hang high pull and mid-thigh pull, and light loads in the jump shrug.

Peak force and peak power output tend to be greater in the mid-thigh power clean, mid-thigh pull and jump shrug weightlifting derivatives than in the power clean, hang power clean, and high pull. The power clean from the ground uses a heavier load than from blocks placed at the knee or mid-thigh. 

Technique can be enhanced by using short rests between repetitions, which reduce variability in horizontal displacement. Visual feedback can also help improve movement patterns. Technique differs in some weightlifting derivatives between more- and less well-trained weightlifters, with more well-trained lifters pulling the bar backwards early in the lift before catching it by moving the bar forwards. 

PRACTICAL PERSPECTIVE

Although learning the formal Olympic lifts may not be a good use of time for athletes, incorporating weightlifting derivatives may be beneficial. Weightlifting derivatives are modified versions of the two main lifts, and include the power snatch, hang snatch, power clean, hang clean, and jump shrug. They are easier to perform and use lighter loads. For maximising force and power output, the mid-thigh power clean, mid-thigh pull, and jump shrug exercises are the best choices. 

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CONTENTS

Full table of contents

  1. Background
  2. Effects of Olympic weightlifting training
  3. Olympic weightlifting biomechanics
  4. Olympic weightlifting injuries
  5. Effects of weightlifting derivative training
  6. Weightlifting derivative biomechanics
  7. References
  8. Contributors

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BACKGROUND

INTRODUCTION

Olympic weightlifting is a sport contested at the summer Olympic games. More correctly referred to as “weightlifting” (Garhammer, 1993; Newton, 1999), the sport involves two barbell exercises called the snatch, and the clean and jerk (Ho et al. 2014). The snatch involves lifting the barbell from the ground to overhead in a single movement. The clean and jerk involves lifting the barbell first to the shoulders in one movement, and then to overhead in a second movement (Ho et al. 2014). The goal of Olympic weightlifting is to put the greatest possible amount of weight overhead in a total calculated across the two lifts (Garhmmer, 1992b; Hedrick & Wada, 2008; Storey & Smith, 2012). Olympic weightlifting has been suggested as a training technique for general power development (Hydock, 2001), as well as for improving performance in many different sports, including rowing (Lawton et al. 2013), volleyball (Cross, 1993; Holmberg, 2013), baseball (Suchomel & Sato, 2013), and rugby (Barr et al. 2014). This is because the two lifts are performed at very high speeds, with great force, and through large ranges of motion (Fortin & Falco, 1997), while producing high power outputs, and are thought to have good transfer to athletic movements (Garhammer, 1993).

PHYSICAL FEATURES OF OLYMPIC WEIGHTLIFTERS

Olympic weightlifters are renowned for having a higher bone mineral density (BMD) or bone mineral content (BMC), having less fat mass, and having a greater amount of muscle mass than normal, healthy control subjects. Many cross-sectional studies have reported greater BMD and BMC in Olympic weightlifters (Virvidakis et al. 1990; Conroy et al. 1993; Karlsson et al. 1995; Heinonen et al. 1993; 2002; Nikander et al. 2005), which is of interest to researchers working to prevent osteoporosis. Additionally, several studies have found that Olympic weightlifters are leaner in comparison with control subjects (Katch et al. 1980; Stoessel et al. 1991), being similar in body composition (around 10% body fat) to bodybuilders during a standard training period (Katch et al. 1980). Finally, Olympic weightlifters routinely display much greater muscle size (Tesch et al. 1984; 1985; 1989)  and muscle mass (Katch et al. 1980) in comparison with control subjects. Additionally, this muscle is more pronounced in areas that contribute to performance in their sport and this differs from the muscular development observed in other strength and power athletes (Katch et al. 1980; Kanehisa et al. 1998; 1999a; Huygens et al. 2002).

PHYSICAL FACTORS ASSOCIATED WITH PERFORMANCE

Introduction

There are many factors that can influence Olympic weightlifting performance. In general, these can be divided into short-term factors, such as recovery status, hydration status, and recent sleep quality and duration (e.g. Blumert et al. 2007) and long-term factors. Long-term factors can be subdivided into psychological areas (e.g. Mahoney, 1989) and (more commonly researched) physical areas, such as age, anthropometrics, muscle fiber type, and strength, which are set out below.

Age

Many studies have assessed Olympic weightlifting ability and its relationship with age, particularly by examining the snatch, clean and jerk, and total performances of masters athletes of varying ages (Ward et al. 1979; Meltzer et al. 1994; Pearson et al. 2002; Thé & Ploutz-Snyder 2003; Anton et al. 2004; Baker & Tang, 2010). In most cases, researchers have concluded that the age-related decline in Olympic weightlifting ability follows a linear path, but non-linear relationships have also been observed (Meltzer et al. 1994). Assessing a range of sports, Wright & Perricelli (2008) noted that the decline in performance increased markedly at >75 years. Where linear relationships are assumed, the reduction in Olympic weightlifting performance seems to be around 1% per year (Meltzer et al. 1994), which is similar to the reduction in power output but is double the rate at which maximum strength is lost (Pearson et al. 2002). When compared with other sports, the reductions in Olympic weightlifting ability with age seem to occur at a greater rate (Baker & Tang, 2010), which may be because of the relationship between the Olympic lifts and power output. In addition, the decreases appear to be more pronounced in females than in males (Anton et al. 2004). The reductions in strength and power observed in masters Olympic weightlifters occur at a similar rate to those in the general population, albeit starting from a higher baseline. When comparing masters Olympic weightlifters with  control subjects, research shows that these athletes are as strong as untrained individuals 20 years younger (Pearson et al. 2002).

Anthropometry

Many studies have assessed the relationships between basic anthropometric measurements and Olympic weightlifting ability (Ward et al. 1979; Sinclair, 1985; Thé & Ploutz-Snyder 2003; Fry et al. 2006; Mattiuzzi & Lippi 2014). Bodyweight and body fat percentage are widely recognised as key drivers, with higher bodyweight and lower body fat percentage being associated with superior ability (Sinclair, 1985; Thé & Ploutz-Snyder 2003; Fry et al. 2006; Mattiuzzi & Lippi 2014). While few successful male Olympic weightlifters are taller than 6’0″ and few successful female Olympic weightlifters are taller than 5’9″ (Ford et al. 2000), body height does not appear to be a key issue that can differentiate between already successful athletes. In addition, although the possession of greater muscle mass or size does differentiate Olympic weightlifters from normal control subjects, it does not appear to differentiate well between elite and sub-elite athletes (Funato et al. 2008; Di Naso et al. 2012). Rather, in such cases, force production is greater per unit cross-sectional area. This lack of a strong relationship differs from observations made in resistance-trained individuals who are not Olympic weightlifters relationships, where a moderate-to-strong association between 1RM power clean and vastus lateralis muscle cross-sectional area has been observed (McMahon et al. 2015).

Muscle fiber type

[Read more: muscle fiber type]

Several studies have investigated the muscle fiber type of Olympic weightlifters and compared it with other athletes (Tesch et al. 1984; Tesch & Karlsson, 1985; Fry et al. 2003). Tesch et al. (1984) reported that vastus lateralis type II fiber proportion was greater in a combined group of Olympic weightlifters and powerlifters than in a group of endurance athletes, but did not differ from an untrained control group. Similarly, Tesch et al. (1985) found that vastus lateralis type II fiber proportion did not differ between a combined group of Olympic weightlifters and powerlifters and a control group, although there were differences with some groups of endurance athletes. However, Fry et al. 2003) found that Olympic weightlifters did display higher type IIA fiber proportion and lower type IIX fiber proportion than untrained controls. Moreover, the type IIA fiber proportion was very closely associated with Olympic weightlifting performance. This may be related to observations that Olympic weightlifters tend to display less step force-velocity curves and can better maintain force production at higher velocities than control subjects (Kanehisa & Fukunaga, 1999).

Strength

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Olympic weightlifting is a strength sport and therefore a certain level of strength is clearly a requirement for participation. Thus, Olympic weightlifters display greater strength than untrained controls (McBride et al. 1999; Harbili, 2015) and track and field sprinters (McBride et al. 1999) but similar strength to powerlifters when measured by 1RM back squat (McBride et al. 1999; Di Naso et al. 2012). Additionally, models have shown that leg strength is a key determinant of snatch performance, while both leg and back strength are determinants of clean and jerk ability (Shetty, 1990). There are some indications that stronger athletes display superior Olympic weightlifting ability and that greater leg strength is associated with Olympic weightlifting performance. Beckham et al. (2013) investigated a wide range of Olympic weightlifters, from novices to advanced athletes. They found that competition results in both the snatch and the clean and jerk correlated strongly with maximum isometric mid-thigh pull force (r =0.83 – 0.84). Haff et al. (2005) explored a smaller group of female Olympic weightlifters and also found close relationships between maximum isometric mid-thigh pull force and the snatch (r =0.93), the clean and jerk (r = 0.64), and the total (r = 0.80). Similarly, Stone et al. (2005) found a strong relationship (r = 0.84) between 1RM squat and 1RM snatch in a group of male and female Olympic weightlifters. However, Funato et al. (2008) compared the isokinetic concentric and eccentric knee extension and flexion torques between elite senior and college Olympic weightlifters. They found that there was no difference between the groups in respect of isokinetic concentric or eccentric knee extension torques, or in respect of eccentric knee flexion torque. The elite Olympic weightlifters did display a greater isokinetic concentric knee flexion torque but the extent to which hamstring strength is relevant to Olympic weightlifting is unclear.

SECTION CONCLUSIONS

Olympic weightlifting (more correctly referred to as “weightlifting”) is a sport contested at the summer Olympic games. The sport involves two overhead barbell lifts called the snatch, and the clean and jerk.

Olympic weightlifters have a higher bone mineral density, less fat mass, and more muscle mass than normal, healthy control subjects. The distribution of the extra muscle mass differs from that in other strength and power sports.

Greater bodyweight, lower body fat percentage, greater type IIA muscle fiber proportion, and greater force producing ability per unit muscle cross-sectional area are all associated with superior Olympic weightlifting ability among Olympic weightlifters.

Stronger athletes are more successful than weaker athletes in Olympic weightlifting. Performance is strongly associated with both maximum isometric mid-thigh pull force and 1RM back squat. The snatch appears to be determined by leg strength but the jerk may be determined by both leg and back strength.

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OLYMPIC WEIGHTLIFTING TRAINING

INTRODUCTION

The best way to train for Olympic weightlifting is a contentious issue. Many coaches and researchers have provided guidance regarding how Olympic weightlifting training should be performed (Thrush, 1995; Storey & Smith, 2012). In general, most elite Olympic weightlifters train very regularly, perhaps twice per day and six days per week (Storey & Smith, 2012). Dividing volume across multiple resistance training sessions per day is thought to allow for better recovery, and thereby improve results (Häkkinen & Kallinen, 1994; Hartman et al. 2007), although where only one training session per day is performed, the afternoon or evening is likely preferable to the morning (Ammar et al. 2015a; 2015b). While some groups have tended to use predominantly the Olympic lifts to the exclusion of other exercises, most programs also make use of a range of supplemental exercises, including weightlifting derivatives (e.g. the hang snatch, hang clean, power snatch, and power clean) and conventional free-weight resistance training exercises, such as front squats, back squats, lunges, the overhead press, back extensions and abdominal exercises (Storey & Smith, 2012). Within the management of Olympic weightlifting training programs, a topic that is often of great concern is the management of overreaching or overtraining, and guidance is often provided regarding this as well (Pistilli et al. 2008).

RUSSIAN AND BULGARIAN METHODS

Introduction

Several reviews have attempted to outline the frameworks and principles used by two of the most dominant Olympic weightlifting groups – the Bulgarian and the Russian national teams (Takano, 1991; Zatsiorsky, 1992; Poletaev & Cervera, 1995). These teams won the majority of the gold medals in Olympic weightlifting at the Olympic games in the 1980s and are therefore widely deemed to have the most effective approaches to training athletes for this sport (Zatsiorsky, 1992). Consequently, many modern programs base their approaches on these models (Garhmmer, 1992b). Indeed, the national Olympic weightlifting teams that have enjoyed success more recently (Greece, Turkey and Iran) are thought to derive their approaches from the Bulgarian model (Garhmmer, 1992b). However, it remains possible that the great success of the programs used by these teams might be driven more by the more extreme use of anabolic androgenic steroids (AAS) compared with other teams than by the specific training methods used (Fair, 1988; Franke & Berendonk, 1997; Storey & Smith, 2012).

The Russian weightlifting method

Outlining the traditional, Russian framework for training for Olympic weightlifting, Poletaev & Cervera (1995) provided some more detail about the way in which the plan is put together. This framework is based on a 4-week cycle, involving a planned amount of volume (number of repetitions), volume load (number of repetitions multiplied by weight), a variety of exercises, and volume of repetitions >90% of 1RM (Poletaev & Cervera, 1995). The supplemental exercises reported included the front and back squats, lunge, good morning, and both the power snatch and power clean from different starting positions (Poletaev & Cervera, 1995).

The Bulgarian weightlifting method

Outlining the Bulgarian framework for training for Olympic weightlifting, Garhmmer (1992b) provided some more detail. The framework involved only six primary exercises (the snatch, clean and jerk, power snatch, power clean and jerk, front squat and back squat) and training sessions were short (around 45 minutes) but are performed three times per day (Garhmmer, 1992b). In addition, training is designed around reaching a daily maximum weight on an exercise for the day, with weight being added as long as the previous lift is successful, up to a total of six lifts in a given exercise.

Comparing Russian and Bulgarian weightlifting methods

In most discussions of the subject, the Russian and Bulgarian methods are very starkly contrasted. The Russian method is characterised as being carefully planned, involving detailed planning and complicated periodisation, a wide variety of exercises, and a high volume of training performed at lower relative loads (Zatsiorsky, 1992; Garhmmer, 1992b; Poletaev & Cervera, 1995; Storey & Smith, 2012). In contrast, the Bulgarian method is characterised as involving much less planning and periodisation (being based around a simple 3-week loading cycle) far fewer exercises (mainly just the competition lifts), and a high volume of training performed at higher relative loads. The relative load is thought to be one of the main issues differentiating the two models. In the Russian system, few lifts are performed at >80% of 1RM and still fewer (around 400 total lifts per year) are performed at >90% of 1RM. In contrast, in the Bulgarian system, far more lifts (between 1,400 – 4,000) are performed at >90% of 1RM (Zatsiorsky, 1992; Storey & Smith, 2012).

Competition 1RM and training 1RM

Although the characterisation of the differences between the Russian and Bulgarian methods of training for Olympic weightlifting described above is now widely accepted, the differences may not be as stark as is generally believed. Zatsiorsky (1992) compared the Russian and Bulgarian methods, noting the main difference between the two groups is the number of lifts reported at >90% of 1RM. According to the calculations made by Zatsiorsky (1992), the Russian teams report just 600 lifts per year, while the Bulgarian athletes report 4,000 such lifts a year. Zatsiorsky (1992) explains that this is not as substantial a difference as immediately appears, as the 1RM used by the Russian method is the competition 1RM, while the Bulgarian approach uses a training 1RM, which is typically around 10 – 15% lower, depending on the weight class. When normalising both classifications to refer to competition 1RM, the number of lifts performed in the Bulgarian system that are >90% of 1RM is much reduced.

DIETARY HABITS

Energy intakes

Food intake is important for Olympic weightlifters to fuel their training and to recover effectively. Consequently, several researchers have analysed the actual dietary practices of Olympic weightlifters (Celejowa & Homa, 1970; Burke & Read, 1988; Chen et al. 1989; Heinemann & Zerbes, 1989; Grandjean, 1989; Van Erp-Baart et al. 1989; Burke et al. 1991; Hassapidou, 2001). Overall, energy intakes generally range between 3,000 – 4,500kcal (Slater & Phillips, 2011; Storey & Smith, 2012), which are exactly within the range of recommended intakes for strength and power athletes put forward by Rogozkin (2000). However, some outliers can be observed, as in the case of the former East German national team, which reported an astonishingly high average energy intake of 7,500kcal per day (Heinemann & Zerbes, 1989; Slater & Phillips, 2011). Despite these apparently quite high intakes, there are indications that athletes are under pressure to maintain a low bodyweight or body fat percentage, as dysfunctional eating behaviours and higher scores on eating disorder scales have been observed in female Olympic weightlifters than normal control subjects (Walberg & Johnston, 1991). This is likely caused by the need to remain within certain weight classes to stay competitive, as reducing bodyweight by up to 4% by rapid methods over the course of a single week has been reported to leave weightlifting performance comparatively unimpaired (Durguerian et al. 2015).

Macronutrient intakes

PROTEIN

Several researchers have analysed the dietary practices of Olympic weightlifters in relation to macronutrient intakes (Burke & Read, 1988; Chen et al. 1989; Heinemann & Zerbes, 1989; Grandjean, 1989; Van Erp-Baart et al. 1989; Burke et al. 1991; Hassapidou, 2001). Protein intake is generally either around 1.6g per kg of bodyweight per day (e.g. Van Erp-Baart et al. 1989) or higher, at up to 3.2g per kg of bodyweight per day (e.g. Chen et al. 1989; Heinemann & Zerbes, 1989). The upper end of this range is considerably higher than the range of recommended intakes of 1.4 – 2.0g per kg of bodyweight per day (Rogozkin, 2000). In general, it is thought that consuming protein above the recommended amounts confers no advantage to strength athletes (Slater & Phillips, 2011).

FAT

Several researchers have analysed the dietary practices of Olympic weightlifters in relation to macronutrient intakes (Burke & Read, 1988; Chen et al. 1989; Heinemann & Zerbes, 1989; Grandjean, 1989; Van Erp-Baart et al. 1989; Burke et al. 1991; Hassapidou, 2001). Based on these analyses, it seems that fat accounts for around 40% of total calories (Heinemann & Zerbes, 1989; Grandjean, 1989; Van Erp-Baart et al. 1989; Chen et al. 1989; Hassapidou, 2001). This is higher than the range of recommended proportion of 25% (Rogozkin, 2000). It seems probable that the high proportion of fat in the diet is a function of the high protein consumption, which is likely achieved by eating a high calorie diet including fatty meats (Storey & Smith, 2012).

CARBOHYDRATE

Probably in consequence of the high proportion of fat in the diet of Olympic weightlifters, carbohydrate intake is generally much lower than standard recommendations for strength and power athletes (Slater & Phillips, 2011), where 55 – 60% of caloric intake is generally proposed (Rogozkin, 2000). As a result, it has been suggested that the amount of carbohydrate consumed might be insufficient to fuel the anaerobic exercise being performed (Storey & Smith, 2012), particularly as strenuous resistance training sessions can deplete muscle glycogen substantially (Slater & Phillips, 2011). However, since no research has been performed investigating the effects of diets with different macronutrient compositions on Olympic weightlifting performance, this hypothesis has not been investigated. Additionally, as Slater & Phillips (2011) have noted, care should be taken before making recommendations regarding the replacement of fat with carbohydrate, if athletes are using fat to achieve energy balance.

ASSOCIATIONS WITH ATHLETIC PERFORMANCE

Introduction

Many researchers have reported strong correlations between performance in the Olympic lifts or weightlifting derivatives and measures of athletic performance. These associations are often taken as justification for including the Olympic lifts or weightlifting derivatives into athletic development programs, on the basis that they might be expected to produce improvements in athletic performance measures (Storey & Smith, 2012). However, strictly this evidence can only be properly deduced from the results of long-term trials, which are outlined later in this section.

Vertical jump and jump squat height or power output

Studies have found that performance in an Olympic lift or a weightlifting derivative is moderate-to-strongly associated with vertical jump height (Hori et al. 2008; Channell & Barfield, 2008; Loturco et al. 2015) as well as vertical jump power output (Carlock et al. 2004; Hori et al. 2008: Nuzzo et al. 2008) and vertical jump peak velocity (Nuzzo et al. 2008). However, the picture is not entirely clear, as Kawamori et al. (2005) reported no relationship between 1RM hang power clean and vertical jump height and Khamoui et al. (2011) reported no relationship between peak force in the mid-thigh pull and vertical jump height. Studies have also observed moderate-to-strong relationships between jump squat height and performance in an Olympic lift (Häkkinen et al. 1986), as well as between jump squat power output and performance in a weightlifting derivative (Baker & Nance, 1999).

Sprint running and agility

[Read more: sprinting]

A small number of studies have found that performance in an Olympic lift or a weightlifting derivative is moderate-to-strongly associated with sprint running speed over short distances (Hori et al. 2008; Loturco et al. 2015) and some investigations have also found an association with change of direction (COD) ability (Hori et al. 2008), although others have not (Loturco et al. 2015).

EFFECTS OF OLYMPIC WEIGHTLIFTING TRAINING

Selection criteria

Population – any healthy population

Intervention – any long-term study assessing the effects of training with Olympic weightlifting exercises (the snatch, and the clean and jerk)

Comparison – baseline

Outcomes – changes in strength, athletic performance measures (sprint running or vertical jumping), weightlifting performance, body composition, and hormone levels

Results

The following relevant studies were identified that met the inclusion criteria: Stone (1983), Häkkinen (1988), Häkkinen (1989), Busso (1992), Fry (1993), Nakao (1995), Hoffman (2004), Tricoli (2005), González-Badillo (2006), Hartman (2007), Wu (2008), Channell (2008), Haff (2008), Hawkins (2009), Siahkouhian (2010), Arabatzi (2010), Crewther (2011), Arabatzi (2012), Chaouachi (2014), Hackett (2015), Storey (2015).

Findings

EFFECTS ON OLYMPIC WEIGHTLIFTING PERFORMANCE

As might be expected, long-term periods of Olympic weightlifting obviously tend lead to increases in performance in the snatch and clean and jerk (Häkkinen et al. 1988; Tricoli et al. 2005; González-Badillo et al. 2006). Although Hartman et al. (2007) and Siahkouhian & Kordi (2010) failed to report increases in performance in either the snatch and clean and jerk in their investigations, the relatively short length of these programs (3 – 4 weeks) was most likely responsible for the lack of any result.

EFFECTS ON LOWER BODY STRENGTH

Most investigations have reported that long-term periods of Olympic weightlifting lead to increases in lower body strength, which are most commonly measured by reference to the 1RM back squat (Hoffman et al. 2004; Tricoli et al. 2005) but also isometric force production (Häkkinen et al. 1988; Haff et al. 2008) and isokinetic torque (Chaouachi et al. 2014). Although Hartman et al. (2007) and Siahkouhian & Kordi (2010) failed to report increases in performance in isometric knee extension torque or 1RM squat, respectively, the relatively short length of these programs (3 – 4 weeks) was most likely responsible for the lack of any result. In some cases, Olympic weightlifting has been reported to increase 1RM back squat to a greater extent than other programs (Hoffman et al. 2004) but other programs have sometimes proved superior, which makes it difficult to draw definitive conclusions about the relative superiority of the training methods (Tricoli et al. 2005).

EFFECTS ON LOWER BODY POWER

Although it is very frequently claimed that Olympic weightlifting is ideal for improving lower body power (e.g. Suchomel et al. 2015b), the literature does not provide unequivocal support for this view at present. Many investigations have reported that long-term periods of Olympic weightlifting do not increase lower body power across many measures (Häkkinen et al. 1988; Hoffman et al. 2004; Hartman et al. 2007; Chaouachi et al. 2014), although equally some investigations have reported improvements (Hawkins et al. 2009; Arabatzi et al. 2012; Chaouachi et al. 2014). It is also frequently claimed that Olympic weightlifting is better than other types of training for improving lower body power (e.g. Suchomel et al. 2015b). However, in direct comparisons with resistance training, this claim is only partly supported by some (Hawkins et al. 2009; Arabatzi et al. 2012; Chaouachi et al. 2014) but not all (Hoffman et al. 2004; Chaouachi et al. 2014) measures. Similarly, direct comparisons of Olympic weightlifting and plyometrics have yielded conflicting results, with some measures showing that Olympic weightlifting is superior (Hawkins et al. 2009; Arabatzi et al. 2012) while others have found no differences (Arabatzi et al. 2012; Chaouachi et al. 2014).

EFFECTS ON VERTICAL JUMPING

Olympic weightlifting is effective for improving vertical jump height (Hoffman et al. 2004; Tricoli et al. 2005; Channell & Barfield, 2008; Hawkins et al. 2009; Arabatzi et al. 2010; Arabatzi et al. 2012; Chaouachi et al. 2014; Hackett et al. 2015). Although Hartman et al. (2007) and Siahkouhian & Kordi (2010) failed to report increases in performance in vertical jump height in their investigations, the relatively short length of these programs (3 – 4 weeks) was most likely responsible for the lack of any result. Performing a meta-analysis of the effects of Olympic weightlifting on vertical jump height in comparison with plyometrics or traditional resistance training, Hackett et al. (2015) reported that Olympic weightlifting was superior to traditional resistance training (by 5.1%) but similar to plyometrics.

EFFECTS ON SPRINT RUNNING

Olympic weightlifting appears to be effective for improving sprint running performance, although few studies have been performed to assess this effect (Hoffman et al. 2004; Tricoli et al. 2005; Chaouachi et al. 2014). Comparing the effects of Olympic weightlifting and traditional resistance training, Hoffman et al. (2004) explored the effects of a 15-week period of training on 40-yard sprint times. The Olympic weightlifting group improved 40-yard sprint time to a greater extent than the traditional resistance training group. Comparing traditional resistance training, plyometrics and Olympic weightlifting, Chaouachi et al. (2014) found that Olympic weightlifting was superior to plyometrics but there was no difference between traditional resistance training and Olympic weightlifting. Tricoli et al. (2005) compared the effects of a resistance training program combined with either Olympic weightlifting (and weightlifting derivatives) or vertical jumping. They found that the Olympic weightlifting group improved 10m sprint time to a greater extent than the vertical jumping group.

CARDIOVASCULAR EFFECTS

Exploring the cardiovascular effects of an 8-week period of Olympic weightlifting training in a controlled trial, Stone et al. (1983) found that VO2-max increased from 39.5 ± 4.2 to 42.4 ± 5.5 ml/min/kg, indicating that maximum aerobic capacity was improved. In contrast, in a 3-year longitudinal observational trial of Olympic weightlifting training, Nakao et al. (1995) found that VO2-max reduced over the first year and then remained constant in the two years thereafter.

BODY COMPOSITION EFFECTS

Exploring the effects of an 8-week period of Olympic weightlifting training on body composition, Stone et al. (1983) found that lean body mass increased from 64.9 ± 7.4 to 67.3 ± 7.7kg, while body fat percentage decreased from 18.9 ± 6.3% to 15.9 ± 6.1%, indicating that body composition was improved. Similarly, in a 3-year longitudinal observational trial of Olympic weightlifting training, Nakao et al. (1995) found that lean body mass increased by 8% after 3 years. Although Hartman et al. (2007) and Siahkouhian & Kordi (2010) failed to report increases in performance in muscle cross-sectional area or lean body mass in their investigations, respectively, the relatively short length of these programs (3 – 4 weeks) was most likely responsible for the lack of any result. Indeed, over a 2-year period of Olympic weightlifting training, Häkkinen et al. (1988) observed 6% increases in size of the vastus lateralis muscle cross-sectional area.

HORMONAL CHANGES

Exploring changes in blood hormone levels with training volume, Häkkinen et al. (1987) found that a 2-week period of high volume Olympic weightlifting led to increases in luteinizing hormone (LH), reductions in serum testosterone (T), reductions in serum testosterone-to-cortisol (T-C) ratio, and reductions in serum testosterone-to-sex hormone binding globulin (T-SHBG) ratio. Subsequently, a period of lower volume Olympic weightlifting led to increases in serum T-SHBG ratio, reductions in serum cortisol (C) and reductions in serum LH. Similarly, during a period of high volume Olympic weightlifting, Busso et al. (1992) observed decreases in serum T and increases in serum LH concentrations. Fry et al. (1993) also observed reductions in serum T and in serum T-C ratio. Both Haff et al. (2008) and Wu et al. (2008) reported an inverse relationship between serum T-C ratio and training volume, with large reductions occurring with increased training volume and increases with reduced training volume. Over a 3-week period, Hartman et al. (2007) observed no changes in serum T, serum C or serum T-C ratio in two groups who performed Olympic weightlifting training with the same volume allocated into either one or two sessions per day. In addition, there were no differences between the groups. Crewther et al. (2011) assessed the effects of a 5-week period of high or low volume Olympic weightlifting training on salivary C levels and reported no changes in either group, or differences between groups. When studying a 2-year period that did not compare different volumes of training, Häkkinen et al. (1988) found that serum T levels were increased, as was the serum T-SHBG ratio, and serum LH levels.

EFFECTS OF TRAINING VOLUME

Exploring the effects of three different volumes during a 10-week training program in groups of Olympic weightlifters, González-Badillo et al. (2006) reported that low and moderate volume programs led to increases in 1RM squat, 1RM clean and jerk, and 1RM snatch. However, the high volume program only led to an improvement in 1RM squat. Additionally, they found bigger improvements in the moderate group than in the low volume group for the 1RM squat (10% vs. 3%) and 1RM clean and jerk (11% vs. 3%). Carrying out a purely observational study, Siahkouhian & Kordi (2010) failed to note any effect of a single week of double volume training, while Storey et al. (2015) noted temporary reductions in vertical jump height and snatch performance, but not in clean and jerk performance, as a result of a similar, single week of very high volume training.

SECTION CONCLUSIONS

Olympic weightlifting training improves snatch and clean and jerk performance, lower body strength (as measured by 1RM squat and isometric force), lower body power output, short distance sprint running ability, vertical jump height, and maximum aerobic capacity (as measured by VO2-max).

Olympic weightlifting training seems to be superior to resistance training but not plyometrics for increasing vertical jump height but whether it is superior to other types of training for any other measure (including lower body power output) is currently unclear.

Olympic weightlifting can produce substantial improvements in body composition, by increasing lean body mass, as well as reducing body fat percentage.

Long-term Olympic weightlifting training seems to increase serum testosterone levels. Temporary periods of high volume Olympic weightlifting training reduce serum testosterone and serum testosterone-to-cortisol ratio, which return to normal during lower volume training. The optimal volume of Olympic weightlifting training for performance enhancements is unclear.

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OLYMPIC WEIGHTLIFTING BIOMECHANICS

METHODOLOGICAL ISSUES

Introduction

Various methodological issues have been identified in relation to the study of Olympic weightlifting (and weightlifting derivative) biomechanics. Perhaps most important among these is the use of two-dimensiononal (2D) data collection methods for motion analysis, which can lead to misrepresentation of the real sagittal plane movements (Ho et al. 2014), although it remains a popular method for assisting coaches because it is easily available and very low cost (Garhammer & Newton, 2013). Recognition of the limitations of 2D analysis has led to the more common usage of three-dimensional (3D) data collection in research, using at least two linked cameras (Ho et al. 2014). Linked to this observation is the fact that the movement at one end of the barbell does not always reflect the movement at other parts of the barbell, either because of deformation of the bar (Chiu et al. 2008; Santos & Meltzer, 2009) or possibly because of asymmetry between sides (Rossi et al. 2007; Lake et al. 2012). Additionally, the exact method of measuring power output may affect the values recored (Garhammer, 1980). Power is both the rate of work done and the product of force times velocity, and therefore can be calculated in several ways, depending on the equipment available. As Garhammer (1980) noted, power output calculated by reference to barbell linear displacement over time will necessarily underestimate the true value, as peak displacement involves a period of deceleration in which no force is applied by the athlete. In contrast, using force plates to calculate force exerted by the athlete should lead to a more accurate result. In contrast to the problem of power outputs, the exact inverse dynamics approach to calculating net joint moments may not exert any substantial effect on the results recorded (Cleather & Bull, 2010).

Reliability

[Read more: reliability]

Another key concern when trying to quantify Olympic weightlifting biomechanics is the reliability of the measurements being taken. While many trials have reported reliability regarding their methods as part of the study protocol, few investigations have made reliability the primary outcome. Brandon et al. (2013) assessed the reliability of a novel analysis system for Olympic weightlifting, comprising surface electromyography (EMG) equipment (to measure EMG amplitude within a muscle), synchronised with electrogoniometry (to measure joint angles), and a barbell position transducer (to measure the height of the barbell and thereby its displacement and linear velocity). When assessing maximal knee angle (flexion), mean power output in the concentric phase a squat exercise, and vastus lateralis EMG amplitude, the test-re-test reliability measured by the coefficient of variation (COV) ranged between 5.3 – 7.8%, which suggests that these measurements are comparatively consistent but not perfectly replicable. Similarly, an accelerometer for measuring barbell acceleration was found to display high but not perfect test-re-test reliability, with an ICC = 0.88 (Sato et al. 2012). While an element of the unexplained variability will likely have arisen though measurement error, it is more likely that the variation occurred primarily through variation between performances within individuals, as snatch, clean and jerk, and total 1RM varies by around 2.3 – 2.7% in elite Olympic weightlifters (McGuigan & Kane, 2004), although test-re-test reliability of the 1RM power clean is nearly perfect in adolescent male athletes, with ICC = 0.98, a standard error of measurement (SEM) of 2.9kg and a smallest worthwhile change (SWC) of 8.0kg (Faigenbaum et al. 2012).

POWER OUTPUT

[Read more: power]

It is now strongly established in tradition that the Olympic lifts and their derivatives are among the best methods of increasing power output. However, such claims rest on relatively shaky ground, as there are few long-term trials to provide evidence. Rather, the tradition has arisen based upon calculations and observations in acute studies (Fletcher et al. 1958; Garhammer, 1980; Garhammer, 1993). And even in this respect, the picture has changed in recent years. Garhammer (1993) produced an influential review in which he compared the acute power outputs during the Olympic lifts and the power lifts. Here, it was suggested that acute power outputs in an elite-level Olympic clean for a heavyweight lifter would be around 4,200W while a deadlift performed by a similar calibre power-lifter in a comparable weight class would be around 1,300W. This was accepted as fact for many years until later studies reported that power outputs during sub-maximal deadlifts are actually comparable with those produced in the Olympic lifts (Swinton et al. 2011). Perhaps more importantly, it has also been found that the power outputs in both Olympic lifts and sub-maximal power lifts are much lower than those produced during vertical jumping, where values can reach 7,000W (Kawamori et al. 2006). And in fact, where the power output of vertical jumps and weightlifting derivatives has been directly compared, it has been discovered that power outputs in the vertical jump exceeds that in the power clean (MacKenzie et al. 2014).

POST-ACTIVATION POTENTIATION

As detailed by Maloney et al. (2014) in their review, there are at least three studies that have investigated the potential post-activation potentiation (PAP) effects of an Olympic lift or weightlifting derivative on subsequent performance (McCann & Flanagan, 2010; Andrews et al. 2011; Chiu & Salem, 2012). All of these studies assessed the effects of the ballistic exercise on subsequent vertical jump height (and power output). Two of the studies used the hang clean exercise (McCann & Flanagan, 2010; Andrews et al. 2011) and one used the power snatch (Chiu & Salem, 2012). However, only Chiu & Salem (2012) reported the presence of an appreciable PAP effect. Whether this was related to the choice of exercise (Maloney et al. 2014) or another reason is unclear.

TECHNIQUE

Introduction

A great deal of guidance has been published regarding the ways in which each of the Olympic lifts should be performed and coached (Vorobyev, 1978; Takano, 1987; 1988; 1993; Javorek, 1986; Medvedev, 1988; Walsh, 1989; Derwin, 1990; Whaley & McClure, 1997; Pierce, 1999; Waller et al. 2009; DeWeese et al. 2012; Favre & Peterson, 2012; DiSanto et al. 2015). Unfortunately, there is very little research assessing whether any of this technique guidance actually improves Olympic weightlifting performance (Ho et al. 2014) and whether any particular cues (or types of cues) are any better than others (Ho et al. 2014).

Phases of the snatch

Traditionally, researchers have analysed the snatch lift by subdividing it into different phases (Garhammer, 1980; Campos et al. 2006; Gourgoulis et al. 2009; Storey & Smith, 2012; Ho et al. 2014; Harbili & Alptekin, 2014). Ho et al. (2014) summarised the literature and presented six different positions, with five phases between each position. These six positions are as follows:

  1. The ground
  2. Barbell at knee level
  3. Power position
  4. Triple extension
  5. Catch in overhead squat
  6. Recovery in standing position

Correspondingly, the five phases that can be described between these positions are as follows: (1) the first pull happens between the ground and when the bar reaches knee level and is initiated by knee and hip extension; (2) the transition happens when the barbell is between knee level and the power position and involves a shift in the position of the body relative to the barbell, which involves a brief period of knee flexion and is therefore referred to as the double knee bend (Enoka, 1979; 1988); (3) the second pull is the most powerful phase of the lift and occurs while the barbell is between the power position and the point at which the lifter achieves triple extension; (4) turnover occurs as the lifter quickly drops down under the bar from the triple extension position to the catch position, in a deep overhead squat; (5) recovery occurs as the lifter stands from the catch position to upright.

Snatch techniques

In the snatch lift, the barbell typically does not travel vertically upwards in a straight line. Rather, there is usually some barbell horizontal displacement both toward and away from the athlete. Researchers and coaches have attempted to analyse and classify patterns of barbell horizontal displacement into different categories. One method of categorisation recognises three types: A, B and C (Vorobyev, 1978; Schilling et al. 2002; Rossi et al. 2007). In category A, the lifter pulls the bar backwards in the first pull, forwards in the second pull, and then as the barbell loops up and overhead, guides the barbell so that it is caught behind. In category B, the lifter again pulls the bar backwards in the first pull, but only pulls minimally forwards in the second pull, and then simply allows the barbell to stop overhead, where it is caught. In category C, the lifter reverses the above technique and pulls the bar forwards at the start of the first pull, then backwards in the second pull, and then as the barbell loops up and overhead, guides the barbell so that it is caught in front (Rossi et al. 2007).

Phases of the clean

Researchers have similarly analysed the clean element of the clean and jerk by subdividing it into different phases (Garhammer, 1980; Storey & Smith, 2012). The clean can similarly be divided into six different positions, with five phases between each position. These six positions are as follows:

  1. The ground
  2. Barbell at knee level
  3. Power position
  4. Triple extension
  5. Catch in front squat
  6. Recovery in standing position

Correspondingly, the five phases that can be described between these positions are as follows: (1) the first pull happens between the ground and when the bar reaches knee level and is initiated by knee and hip extension; (2) the transition happens when the barbell is between knee level and the power position and involves a shift in the position of the body relative to the barbell, which involves a brief period of knee flexion and is therefore referred to as the double knee bend (Enoka, 1979; 1988); (3) the second pull is the most powerful phase of the lift and occurs while the barbell is between the power position and the lifter is in triple extension; (4) turnover occurs as the lifter quickly drops down under the bar from the triple extension position to the catch position, in a deep front squat; (5) recovery into the standing position occurs as the lifter stands from the catch position to upright.

Jerk technique

Researchers have similarly analysed the jerk element of the clean and jerk by subdividing it into different phases (Garhammer, 1980; Storey & Smith, 2012). The jerk can be divided into six different positions, with five phases between each position. These six positions are as follows:

  1. Standing upright, with the barbell at the shoulders
  2. Dip position
  3. Jerk drive
  4. Mid-air split position
  5. Ground split position
  6. Recovery in standing position

Correspondingly, the five phases that can be described between these positions are as follows: (1) from the standing position, the athlete performs a dip, involving knee and hip flexion; (2) from the lowest point of the dip, where knee and hip flexion are greatest, the athlete performs the jerk drive by jumping upwards, which launches both the athlete and the barbell into the air; (3) as the athlete’s feet leave the ground, they reposition them under the barbell to form an unsupported split in mid-air; (4) from the unsupported split position in mid-air, the athlete falls briefly and lands on the ground while holding the weight overhead, ending in the supported split position; (5) from this supported split position on the ground, the athlete recovers by moving the back foot forwards to joint the front foot in a feet parallel position.

BIOMECHANICS OF THE SNATCH

Selection criteria

Population – any population with weightlifting experience

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the snatch lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Garhammer (1980), Garhammer (1982), Burdett (1982), Häkkinen (1984), Garhammer (1985), Baumann (1988), Garhammer (1992a), Isaka (1996), Hiskia (1997), Stone (1998), Garhammer (1998), Gourgoulis (2000), Garhammer (2001), Gourgoulis (2002), Burnett (2002), Schilling (2002), Gourgoulis (2004), Campos (2006), Hoover (2006), Coker (2006), Rossi (2007), Nejadian (2008), Okada (2008), Gourgoulis (2009), Chiu (2010), Saxby (2011), Ho (2011), Akkuş (2012), Ikeda (2012), Hadi (2012), Harbili (2012), Chen (2013), Harbili (2014), Musser (2014), Rahmati (2014), Tang (2014), Whitehead (2014), Wicki (2014), Lin (2015), Korkmaz (2015).

Findings

BARBELL VERTICAL DISPLACEMENT

Maximum barbell vertical displacement prior to the catch in the snatch lift ranges between 1.0 – 1.3m (Baumann et al. 1988; Garhammer, 1985; Garhammer, 2001; Campos et al. 2006; Gourgoulis et al. 2002; 2004; 2009; Okada et al. 2008; Akkuş, 2012; Harbili, 2012; Ho et al. 2014; Harbili & Alptekin, 2014) but decreases with increasing load (Garhammer, 1985; 2001; Hadi et al. 2012) and is greater in males than in females (Gourgoulis et al. 2002) but smaller in more skilled athletes than in less skilled athletes (Burdett et al. 1982). Maximum barbell vertical displacement is thought to be around 70% of body height (Campos et al. 2006; Ho et al. 2014). The barbell vertical displacement in the first and second pull phases tends to be around 0.50m and 1.0m, respectively (Gourgoulis et al. 2009; Harbili, 2012; Akkuş 2012; Harbili & Alptekin, 2014).

BARBELL HORIZONTAL DISPLACEMENT

Many researchers have found that the bar moves horizontally toward the athlete in the first pull, away in the second pull, and back again in the catch phase. Garhammer (1985) found that the barbell moved by around 3 – 9cm in the first pull, by around 3 – 18cm in the second pull, and by around 3 – 9cm in the catch phase. Based on more recent studies, the upper ends of these ranges are likely slightly larger than occur in modern elite lifters, with most studies reporting that the backward displacement in the first pull is around 4 – 7cm and the forward displacement in the second pull is around 2 – 7cm (Okada et al. 2008; Gourgoulis et al. 2002; 2009; Harbili, 2012; Akkuş, 2012; Harbili & Alptekin, 2014). It is unclear whether there are differences between males and females, as reports are conflicting (Gourgoulis et al. 2002; Harbili, 2012).

OPTIMAL LIFTING TECHNIQUE

Although modelling studies have been performed to identify optimal barbell trajectories (Nejadian et al. 2008), it may be that no consistent pattern of barbell horizontal displacement is associated with optimal performance. Gourgoulis et al. (2009) found that there was no difference in barbell horizontal displacement between successful and unsuccessful snatch lifts. And Whitehead et al. (2014), Chiu et al. (2010) and Musser et al. (2014) all found no relationship between the pattern of barbell horizontal displacement and weightlifting ability. In contrast, Lin et al. (2015) observed that superior weightlifters displayed less horizontal displacement the barbell. Interestingly, Garhammer (2001) showed that the pattern of barbell horizontal displacement changes with increasing load even in elite weightlifters, and Musser et al. (2014) reported that barbell horizontal displacement may be at least partly determined by anthropometry, as barbell horizontal displacement in the first pull was associated with thigh and shank lengths in female Olympic weightlifters.

PREVALENCE OF BARBELL TRAJECTORY CLASSIFICATION

Studies assessing the tendency for lifters to display either type A, B, or C barbell trajectories have not all reported similar results (Isaka et al. 1996; Hiskia, 1997; Garhammer, 1998; Stone et al. 1998; Schilling et al. 2002; Gourgoulis et al. 2002; Hoover et al. 2006; Rossi et al. 2007). Rossi et al. (2007) reported that most athletes used the type C trajectory, which was unexpected, as traditional observations tend to assume that the athlete will always pull the barbell towards them at the outset of the lift (Baumann et al. 1988). Even so, a comparatively high proportion of this type of lift trajectory has been observed in other weightlifters (Hoover et al. 2006). Schilling et al. (2002) suggested that barbell trajectories might be affected by actual feet displacement during the lift, as previous studies had observed that some lifters often jumped either forwards or backwards to catch the barbell at the end of the lift (Garhammer, 1985; Isaka et al. 1996). Schilling et al. (2002) confirmed that horizontal displacement of the feet was correlated with barbell horizontal displacement (r = ? 0.75).

BARBELL LIFT DURATION 

In the snatch lift, time to peak velocity is 0.6 – 0.8 seconds and time to peak vertical displacement prior to the catch is 0.9 – 1.1 seconds (Garhammer, 1985; Campos et al. 2006; Gourgoulis et al. 2009). Studies uniformly identify the first pull as the longest phase (Gourgoulis et al. 2002; Harbili, 2012; Korkmaz & Harbili, 2012; Akkuş, 2012; Harbili & Alptekin, 2014; Harbili, 2015). The individual durations of the first pull, transition, second pull, turnover, and catch phases of the snatch are around 0.45 – 0.55, 0.1 – 0.15, 0.15, 0.25, and 0.30 – 0.35 seconds, respectively (Gourgoulis et al. 2002; Campos et al. 2006; Gourgoulis et al. 2009; Harbili, 2012), with no differences between successful and unsuccessful lifts (Gourgoulis et al. 2009) but with heavier athletes and heavier loads spending a larger proportion of total lift time in the first pull (Campos et al. 2006; Hadi et al. 2012). Some studies have reported no differences in respect of individual phase durations between males and females (Harbili, 2012) while others have reported longer durations of the turnover and second pull phases in females (Gourgoulis et al. 2002).

BARBELL VERTICAL VELOCITY

In the snatch lift as performed in competition, peak vertical bar velocity can reach 2.1m/s (Garhammer, 1985; Okada et al. 2011) and the second pull is the fastest phase of the lift (Campos et al. 2006; Harbili, 2012; Korkmaz & Harbili, 2012; Akkuş, 2012; Harbili & Alptekin, 2014; Harbili, 2015), although peak vertical bar velocity is even higher with sub-maximal loads (Hadi et al. 2012). In a range of studies in senior and junior male and female Olympic weightlifters, peak vertical bar velocities in the first and second pull phases were 1.0 – 1.3m/s and 1.7 – 1.8m/s, respectively (Baumann et al. 1988; Campos et al. 2006; Gourgoulis et al. 2009; Harbili, 2012; Akkuş, 2012; Harbili & Alptekin, 2014). Peak vertical bar velocity achieved by the females appears to be greater than that reported for the males (Gourgoulis et al. 2002; Harbili, 2012). Peak vertical bar velocity achieved by heavier male junior weightlifters also appears to be greater than that reported for the lighter weight classes (Campos et al. 2006). Whether this is a function of anthropometry is currently unclear.

GROUND REACTION FORCES

Greater loads in the snatch are associated with greater ground reaction forces (GRFs), both between athletes and within athletes. Wicki et al. (2014) found that vertical GRF was greater when using 70% than with 30% of 1RM. Similarly, Baumann et al. (1988) found that heavier classes of weightlifter displayed higher GRFs, with lightweight (60kg) athletes displaying around 2,500N and heavyweight (150kg) athlete displaying around 4,000 – 4,300N of force.

POWER OUTPUTS

Power output actually increases with increasing load in the snatch lift (Hadi et al. 2012) is greater during the snatch lift in the second pull than in the first pull, being around 2,000 – 3,000W in the second pull phase and 600 – 1,000W in the first pull phase (Garhammer, 2001; Gourgoulis et al. 2009; Harbili, 2012; Akkuş, 2012; Harbili & Alptekin, 2014). There appears to be little difference in power outputs between maximal and near-maximal loads (Harbili & Alptekin, 2014) or between successful and unsuccessful snatch lifts (Gourgoulis et al. 2009), although power output is much greater in males than in females (Harbili, 2012).

JOINT ANGULAR VELOCITIES

Joint angular velocities in Olympic weightlifting are extremely fast, with the knee angular velocity being the fastest of the three joints in the first pull phase, and the hip angular velocity being the fastest of the three joints in the second pull phase. In the first pull phase, peak hip, knee and ankle joint angular velocities are around 120 – 180, 170 – 250, and 70 – 100 degrees/s, respectively (Gourgoulis et al. 2002; 2009; Akkuş, 2012; Harbili, 2012; Harbili & Alptekin, 2014). Only peak hip extension angular velocity is affected by load, being faster with greater weight (Harbili & Alptekin, 2014). Hip extension angular velocity is affected by gender, being higher in males than in females (Harbili, 2012), and some reports indicate that knee extension angular velocity may also be affected by gender, being higher in males than in females (Gourgoulis et al. 2002), although this has not been confirmed by all studies  (Harbili, 2012). In the second pull phase, peak hip, knee and ankle joint angular velocities are around 420 – 470, 280 – 400, and 210 – 370 degrees/s, respectively (Gourgoulis et al. 2002; 2009; Akkuş, 2012; Harbili, 2012; Harbili & Alptekin, 2014) and are not affected by the load used (Harbili & Alptekin, 2014) or whether the lift was successful (Gourgoulis et al. 2009). Ankle extension angular velocity is higher in females than in males in this phase (Gourgoulis et al. 2002; Harbili, 2012) and hip extension velocity may also be greater (Harbili, 2012).

NET JOINT MOMENTS

Overall, the net hip joint moment observed in maximal snatch lifts seems to be much larger than the net knee joint moment, even though Olympic weightlifting is often regarded as being a sport requiring substantial knee extension strength. Saxby & Robertson (2011) reported that the peak hip, knee and ankle net joint moment during both successful and unsuccessful snatch lifts were 315Nm, 174Nm, and 269Nm and 312Nm, 212Nm and 265Nm, respectively. Similarly, Baumann et al. (1988) reported that in lightweight (60kg) athletes, peak hip and knee net joint moments were 260 – 300Nm and 60 – 100Nm, respectively, while in heavyweight (150kg) athletes, peak hip and knee net joint moments were 560 – 660Nm and 175 – 185Nm, respectively.

EMG AMPLITUDE

Exploring EMG amplitude in the deltoid, biceps, triceps, pectoralis major, and latissimus dorsi muscles across the different phases of the snatch, Chen et al. (2012) assessed the effect of using a range of light, moderate and heavy loads. They found that EMG amplitude increased with increasing load in the deltoid only in the second pull, turnover, and recovery phases; in the biceps in the transition, second pull, turnover, and recovery phases; in the triceps only in the recovery phase, in the latissimus dorsi only in the first phase, and not at all in the pectoralis major. These findings underscore the importance of the latissimus dorsi in the early part of the lift and of the deltoids and arm muscles later in the lift.

EFFECT OF LOAD

In most analyses of Olympic weightlifting performed by Olympic weightlifters, the loads used are in competition and are therefore maximal or near-maximal. Comparing the effect of load during the snatch in Olympic weightlifters, Wicki et al. (2014) found that vertical ground reaction force (GRF) was greater when using 70% than with 30% of 1RM, but neither average nor peak rate of force development (RFD) differed between conditions. Also comparing the effect of load but using near-maximal and maximal loads, Harbili & Alptekin (2014) found that when comparing the maximal load to the near-maximal load, there was a reduction in both peak barbell vertical displacement (1.25 vs 1.27m) and peak vertical barbell velocity (1.72 vs. 1.82m/s). However, Ho et al. (2011) did not find any effect of load on peak barbell velocity across 133 attempts by a single weightlifter.

EFFECT OF EXTERNAL LOADING

Comparing the use of a barbell or a barbell plus chains for the snatch lift, using 75% or 80% of 1RM with 5% of chains replacing the same weight of barbell, Coker et al. (2006) found that there was no difference between conditions in relation to maximum vertical displacement of the bar, maximum bar velocity, RFD, and vertical GRF for the first pull, unweighting, and second pull phases of the snatch lift. However, the subjects rated the snatch with chains as perceptually more difficult to perform.

LOW BACK JOINT LOADS

Exploring low back joint loads in the snatch in nationally-ranked Olympic weightlifters weighing 94.1kg on average, Burnett et al. (2002) reported that compressive forces at the L5-S1 joint were 7,020 ± 1,463N (6.5 ± 1.1 times bodyweight), while shear forces were were 1,065 ± 112N (1.0 ± 0.1 times bodyweight). In a comparable study, Cholewicki et al. (1991) investigated low back joint loads in the deadlift in nationally-ranked powerlifters. In a lifters in the 90kg weight class, compressive forces at L4-L5 were 14,487 ± 1,282N and shear forces were 1,673 ± 104N. This indicates that although low back joint loads are high in the Olympic lifts, they do not appear to be as high as in the deadlifts performed by athletes of comparable status.

Summary

Maximum barbell vertical displacement prior to the catch in the snatch lift decreases with increasing load, is greater in males than in females, but smaller in more skilled athletes than in less skilled athletes.

In the snatch lift, the bar generally moves horizontally toward the athlete in the first pull, away in the second pull, and back again in the catch phase. The prevalence of different patterns used by lifters is unclear, and it is unknown whether one pattern is optimal. Patterns may be affected by both the load used and anthropometry.

The snatch lift has two pull phases, with the first being longer than the second. Heavier athletes and heavier loads involve a larger proportion of total lift time in the first pull. The second pull involves greater power outputs than the first pull. In the first pull, knee extension angular velocity is greatest, while in the second pull, hip extension velocity is greatest.

Hip extension net joint moments are very large in the snatch lift, with heavyweight lifters achieving 660Nm. In comparison, knee extension moments appear to be much smaller. This underscores the importance of the hip extensors for Olympic weightlifting success.

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BIOMECHANICS OF THE CLEAN

Selection criteria

Population – any population with weightlifting experience

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the clean lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Enoka (1979), Garhammer (1980), Häkkinen (1984), Garhammer (1985), Enoka (1988), Garhammer (1991), Collins (1994), Burnett (2002), Berning (2008), Anderson (2008), Eriksson Crommert (2013), Moolyk (2013), Calatayud (2015).

Findings

BAR PATH

Exploring the direction of the bar path during the clean pull, Garhammer (1985) found that the barbell moved horizontally toward the athlete during the first pull by around 3 – 9cm, horizontally away from the athlete in the second pull by around 3 – 18cm, and finally horizontally toward the athlete during the catch phase by around 3 – 9cm. In contrast, there was minimal horizontal displacement of the barbell during the jerk phase. Anderson et al. (2008) reported a similar pattern of movement. They also noted that the variability between similar efforts was not different between elite, experienced and novice Olympic weightlifters was similar, suggesting that the traditional idea that greater experience leads to less variability in movement patterns is false.

LIFT DURATION AND BAR VELOCITY

The time taken to perform the clean pull to the point of peak velocity is around 0.7 – 0.9 seconds (Enoka, 1988; Garhammer, 1985) and the time taken to reach peak vertical displacement is around 0.9 – 1.1 seconds, at a bar velocity of 1.5 – 2.2m/s (Garhammer, 1985; 1991). Exploring the effect of load by taking measurements during the first pull and transition phases of the clean with 69%, 77% and 86% of 1RM, Enoka (1988) found that the duration of the pull tended to increase with increasing load (0.76 to 0.84 seconds). Exploring bar velocities in elite female Olympic weightlifters in competition, Garhammer (1991) found that peak barbell velocity ranged between 1.5 – 2.2m/s, and Garhammer (1985) reported similar values of 1.5 – 2.1m/s in male gold medalists at the 1984 Olympic games, indicating that there is little difference between genders. Overall peak velocity occurs during the second pull, while the peak velocity in the first pull is typically much lower at around 1.05 – 1.62m/s (Garhammer, 1985). Given that these velocities are recorded when using competition loads, it is not unreasonable to assume that higher peak barbell velocities would be expected with sub-maximal loads (Storey & Smith, 2012).

GROUND REACTION FORCE (GRF)

Exploring the ground reaction force (GRF) during the first and second pulls of a clean, Enoka (1979) reported that the GRF was greater in the second pull phase than in the first pull phase (2,471 vs. 2,809N).

POWER OUTPUTS

Exploring power outputs in different phases of the clean and jerk in athletes competing at the 1975 USA National Weightlifting Championships, Garhammer (1980) found that power outputs were lower in the first pull phase (1,305 – 3,273W) than in the second pull phase (2,206 – 4,758W) or jerk drive phase (2,503 – 4,786W). The jerk drive phase of the lift sometimes displayed greater power outputs than the second pull but sometimes lower power outputs. Garhammer (1985) presented similarly high power outputs during the second pull and jerk drive phases in athletes competing in the 1984 Olympic games (3,142 – 5,442W). Enoka (1988) explored hip, knee and ankle joint power outputs in competitive weightlifters during the first pull and transition phases and reported that joint peak power output did not alter with increasing load at the hip, knee or ankle. However, joint average power output at the knee increased substantially with increasing load (from 0.94 ± 0.55 to 1.38 ± 0.43W/kg).

EFFECT OF EXTERNAL LOADING

Comparing the use of a barbell or a barbell plus chains for the clean, using 75% or 80% of 1RM with 5% of chains replacing the same weight of barbell, Berning et al. (2008) found that there was no difference between conditions in relation to peak vertical displacement, peak velocity or rate of force production in the first-pull, transition, or second-pull phases of the clean. However, the subjects rated the clean with chains as perceptually more difficult to perform. Calatayud et al. (2015) explored trunk muscle electromyography (EMG) amplitude during the clean and jerk in amateur subjects with a 20kg barbell and with the same load using sandbags or water bags. There was no difference between the barbell and the sandbags but the water bags involved greater external oblique, lumbar erector and gluteus medius EMG amplitude.

LOW BACK JOINT LOADS

Exploring low back joint loads in the clean in nationally-ranked Olympic weightlifters weighing 94.1kg on average, Burnett et al. (2002) reported that compressive forces at the L5-S1 joint were 8,569 ± 1,825N (6.7 ± 0.8 times bodyweight), while shear forces were 1,176 ± 211N (0.9 ± 0.1 times bodyweight). These values were very similar to the snatch performed in the same athletes, where compressive forces were 7,020 ± 1,063N (6.5 ± 1.1 times bodyweight) and shear forces were 1,065 ± 112N (1.0 ± 0.1 times bodyweight). In a comparable study, Cholewicki et al. (1991) investigated low back joint loads in the deadlift in nationally-ranked powerlifters. In a lifters in the 90kg weight class, compressive forces at L4-L5 were 14,487 ± 1,282N and shear forces were 1,673 ± 104N. This indicates that although low back joint loads are high in the Olympic lifts, they do not appear to be as high as in the deadlifts performed by athletes of comparable status.

TRUNK MUSCLE FUNCTION

Exploring trunk muscle EMG amplitude and intra-abdominal pressure (IAP) during the clean and jerk exercise, Eriksson Crommert et al. (2013) took several measurements while amateur subjects performed the exercise with a 30kg barbell both dynamically and holding static positions at varying points during the lift. They found that the transverse abdominis was most active when the barbell was at or above shoulder level, while erector spinae EMG amplitude and IAP were greatest when the barbell was at mid-shin level. The rectus abdominis and internal obliques tended to display low EMG amplitude at all points. Calatayud et al. (2015) similarly explored trunk muscle EMG amplitude during the clean and jerk in amateur subjects with a 20kg barbell. They found that external oblique EMG amplitude was comparatively low (>30% of maximum voluntary isometric contraction [MVIC] levels) but erector spinae EMG amplitude was high (74 ± 4% of MVIC). These findings indicate that the abdominals are likely not strongly involved in the performance of the clean and jerk ability, while the erector spinae is much more important.

Summary

In the clean, the barbell moves horizontally toward the athlete during the first pull, away from the athlete in the second pull, and back toward the athlete in the catch phase. Superior Olympic weightlifting ability in the clean does not automatically lead to greater consistency in movement patterns.

Ground reaction forces and power outputs are greatest in the second pull phase of the clean. Transverse abdominis EMG amplitude is greatest when the barbell is at shoulder level, while erector spinae EMG amplitude and IAP are greatest when the barbell is at mid-shin level.

Although low back joint compressive and shear forces in the clean performed by elite Olympic weightlifters are high (around 8,600N and 1,200N, respectively), they are not as high as in the deadlift performed by elite powerlifters of similar bodyweight (around 14,500N and 1,700N, respectively).

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BIOMECHANICS OF THE JERK

Selection criteria

Population – any population with weightlifting experience

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the jerk lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Garhammer (1980), Cleather (2013a); Cleather (2013b).

Findings

POWER OUTPUT

Exploring power outputs in different phases of the clean and jerk, Garhammer (1980) found that power outputs in the jerk ranged between 2,503W for the lightweight lifters (52kg) and up to 4,786W for heavyweight lifters (110kg). The jerk phase of the lift often displayed the greatest power outputs during the clean and jerk (as in the 52kg, 60kg, 100kg and 110kg lifters measured) but it also often displays the second greatest power outputs after the second pull phase (as in the 82.5kg, 100kg, and 142kg lifters measured).

GROUND REACTION FORCE (GRF) AND JOINT LOADS

Exploring joint loads, Cleather et al. (2013a) measured the internal joint forces experienced by the lower limb during vertical jumping, jump landing, and push jerking with a 40kg load. For all of the movements, GRF was in the range 1.1 – 1 .6 times bodyweight, which is not unexpected given that the loading of the jerk was relatively small in comparison with what can be lifted. Similarly, for all of the movements, the loading at the ankle joint was highest, at 8.9 – 10.0 times bodyweight, followed by the loading at the tibiofemoral joint, at 6.9 – 9.0 times bodyweight, followed by the loading at the hip joint, at 5.5 – 8.4 times bodyweight. The extent to which the jerk would continue to display similar loading patterns to the vertical jump when loaded more heavily is, however, unclear.

NET JOINT MOMENTS

Exploring net joint moments, Cleather et al. (2013b) measured the net joint moments experienced by the lower limb during vertical jumping, jump landing, and push jerking with a 40kg load. The net moments joint moments were similar at the ankle across the three movements but knee moments were greater in the jerk (2.34 ± 0.46 times bodyweight) than in either the jump (1.65 ± 0.21 times bodyweight) or the jump landing (1.75 ± 0.51 times bodyweight). Similarly, the hip moments were greater in the jump (1.56 ± 0.21 times bodyweight) than in the jump landing (1.05 ± 0.43 times bodyweight) or jerk (0.61 ± 0.48 times bodyweight). Thus, the jerk displayed a much more knee-dominant net joint moment profile than the jump or jump landing. This may be because the trunk is restricted from moving during this movement as a result of maintaining the barbell overhead (Cleather et al. 2013b).

Summary

The jerk is a much more knee-dominant movement than the vertical jump or jump landing, probably because the trunk is restricted from moving during this movement as a result of maintaining the barbell overhead. Training the jerk may require improving knee extension strength, and the jerk may transfer best to movements requiring substantial net knee joint moments.

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SECTION CONCLUSIONS

Although the Olympic lifts are frequently described as good exercises for developing power output, they produce similar power output to sub-maximal power lifts and substantially less power output than vertical jumps.

The Olympic lifts or weightlifting derivatives may be able to produce a post-activation (PAP) effect on subsequent vertical jump height, although this may be affected by the type of exercise variation used.

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OLYMPIC WEIGHTLIFTING INJURIES

RISK AND REWARD

Introduction

For many years, there has been debate regarding the injury risk associated with resistance training in general and Olympic weightlifting training in particular. The main question of interest is whether the apparent risks outweigh the potential benefits (called the risk-reward ratio). In respect of Olympic weightlifting training, there are four main populations for which this question needs to be answered: Olympic weightlifters, adult athletes, youth athletes, and the general population. Obviously, Olympic weightlifters need to perform Olympic weightlifting training in order to compete in their sport and indeed it is often pointed out that the risk of injury in this sport is lower than in many popular team sports (Hedrick & Wada, 2008). Similarly, from a public health perspective, there is no need for the general population to spend time learning the technical aspects of Olympic weightlifting when they can attain similar health and fitness benefits from far less difficult resistance training methods that are more widely available. This therefore leaves the question of whether the risk-reward ratio for Olympic weightlifting training is acceptable for adult and youth athletes who do not compete in Olympic weightlifting.

Risk-reward ratio

The risk-reward ratio is the assessment of whether the apparent risks outweigh the potential benefits. The risk element assesses whether the risk of performing the activity is higher or lower than the nearest available comparison, while the reward element assesses whether the reward of performing the activity is higher or lower than the nearest available comparison. In the case of Olympic weightlifting training for adult and youth athletes not competing in Olympic weightlifting, the risk to assess is whether the injury incidence is greater than that of conventional resistance training, while the reward to assess is whether the enhancements in athletic performance measures are greater than those produced by conventional resistance training.

Injury risk

There are two very different viewpoints regarding the relative injury risks of Olympic weightlifting training and conventional resistance training. On the one hand, it has been argued that (when properly supervised and performed), Olympic weightlifting training is no more injurious than any other form of resistance training (Hedrick & Wada, 2008). On the other hand, it has been argued that Olympic weightlifting training is clearly much more dangerous than other forms of resistance training, particularly those that involve bodyweight, machine weights, or elastic bands as the primary mode of external loading (Bruce-Low & Smith, 2007; Fisher et al. 2014).

Performance benefits

There are fairly clear indications that Olympic weightlifting training is beneficial for the development of lower body strength and athletic performance. However, it is unclear whether Olympic weightlifting training is superior to conventional resistance training for the development of athletic performance. In this respect, there are some indications that Olympic weightlifting might be better than traditional resistance training for developing vertical jumping ability, as reported by a recent meta-analysis (Hackett et al. 2015). However, although Olympic weightlifting training does seem to produce improvements in sprint running performance (Hoffman et al. 2004; Tricoli et al. 2005; Chaouachi et al. 2014), there are currently no grounds for believing that it achieves superior results to any other form of conventional resistance training.

Olympic weightlifting or weightlifting derivatives?

One complicating factor that makes it difficult to assess the risk-reward ratio of Olympic weightlifting training in relation to conventional resistance training is the differences between Olympic weightlifting and weightlifting derivatives. Currently, it is unclear whether the same performance benefits could be achieved using weightlifting derivatives as when using Olympic weightlifting training. Biomechanically, there are great similarities and logically it would seem that similar benefits could be achieved using both forms of training. However, the risk of many weightlifting derivatives (e.g. the high pull) would appear on the face of it to be lower than the risk of performing the Olympic lifts, since the barbell is not either caught or placed overhead.

REPORTED INJURIES

Selection criteria

Population – any population with weightlifting experience

Intervention – any observational study assessing the incidence or nature of injuries during

Comparison – between populations

Outcomes – description of injuries, injury incidence, injury prevalence, or injury rate

Results

The following relevant studies were identified that met the inclusion criteria: Kotani (1971), Zernicke (1977), Aggrawal (1979), Fitzgerald (1980), Longhurst (1980), Pearson (1986), Dangles (1987), Fleck (1989), Rossi (1990), Fleck (1993), Hamill (1994), George (1998), Calhoon (1999), Raske (2002), Lalande (2007), Gratzke (2007), Eng (2008), Junge (2009), Grzelak (2012), Engebretsen (2013), Grzelak (2014), Grzelak (2015), Payne (2015).

Findings

OVERUSE JOINT INJURY (INCL. SPONDYLOLYSIS)

Several early reports found that Olympic weightlifters might be more prone to develop overuse joint injury than other groups, predominantly in the spine (Kotani et al. 1971; Aggrawal et al. 1979; Dangles & Spencer, 1987; Rossi & Dragoni, 1990) but also at the knee (Fitzgerald & McLatchie, 1980; Grzelak et al. 2015; Payne et al. 2015). Additional studies have found evidence of thickening of the ligaments and articular cartilage of the knee, which indicates an adaptive response to substantial mechanical loading over time (Gratzke et al. 2007; Grzelak et al. 2012a; 2012b; 2014) as well as acute patellar tendon rupture during competition (Zernicke et al. 1977). However, many of these investigations used small sample sizes and they also often noted that other strength and power athletes such as powerlifters or track and field athletes were prone to the same conditions, albeit perhaps not always to the same extent (Aggrawal et al. 1979; Fitzgerald & McLatchie, 1980; Rossi & Dragoni, 1990).

INJURY PREVALENCE

Exploring the prevalence of injury in elite Olympic weightlifters in a competition period, Junge et al. (2009) reported the prevalence of injury in Olympic weightlifting during the 2008 Beijing Summer Olympic Games. Engebretsen et al. (2013) similarly reported the prevalence of injury in Olympic weightlifting during the 2012 London Summer Olympic Games. Junge et al. (2009) found that 43 injuries were sustained in 255 athletes (17%). Similarly, Engebretsen et al. (2013) found that 44 injuries were sustained in 252 athletes (18%). The large majority of injuries were sustained during competition rather than during training but overuse was cited as a key driving factor in >40% of cases. In both studies, the researchers grouped Olympic weightlifting with other sports in which the risk of injury was highest.

INJURY INCIDENCE

Exploring the incidence of injury during Olympic weightlifting training in a group of elite Olympic weightlifters over a 6-year period, Calhoon & Fry (1999) reported that the incidence was 3.3 injuries per 1,000 hours. Similarly, investigating the injuries incurred during Olympic weightlifting training in a group of elite Olympic weightlifters over a 2-year period, Raske & Norlin (2002) found that the incidence was 2.4 injuries per 1,000 hours. These statistics are within the range observed in powerlifting, which is between 0.84 – 4.4 injuries per 1,000 hours (Brown & Kimball, 1983; Keogh et al. 2006), but slightly lower than the figures currently observed for the popular sport of strongman, which has been reported at 5.5 injuries per 1,000 hours (Winwood et al. 2014). For context, these figures are at the lower end of the scale reported across several studies into injuries incurred as a result of long distance running, which range between 2.5 – 12.1 injuries per 1,000 hours of training (Van Mechelen, 1992).

INJURY LOCATION

The most commonly-injured parts of the body in Olympic weightlifting are not entirely clear. It was originally suggested that most injuries resulting from Olympic weightlifting training occur mainly at the wrist, shoulder and knee and not at the low back (Fortin & Falco, 1997) and it is reported that many strength coaches still avoid the Olympic lifts in the belief that injuries occur to the wrist and shoulder (Suchomel et al. 2015b). However, more recent research suggests that the main areas of injury when Olympic weightlifting are the low back and knee, with the shoulder being injured less frequently. Calhoon & Fry (1999) found that the low back accounted for the majority of injury cases reported in a 6-year observational trial (23%), followed by the knee (19%), then shoulder (18%), and hand (10%). Similarly, Raske & Norlin (2002) found that injury incidences at the low back and knee were both high (each 0.5 injuries per 1,000 hours), followed by the shoulder (0.3 injuries per 1,000 hours), and then the elbow and wrist (each 0.2 injuries per 1,000 hours), and upper back (0.2 injuries per 1,000 hours).

CARDIAC STRUCTURE ALTERATIONS

Left ventricular hypertrophy within the heart muscle is an independent risk factor for cardiovascular events (Storey & Smith, 2012). Several studies have found left ventricular enlargement within the heart in Olympic weightlifters in comparison with sedentary control subjects (Longhurst et al. 1980; Pearson et al. 1986; Fleck et al. 1989; 1993; George et al. 1998; Lalande & Baldi, 2007). This change in cardiac morphology is thought to occur as a result of the increased peripheral vascular resistance that happens during any form of resistance training (Storey & Smith, 2012). It may be an adaptation that is intended to reduce stress on the left ventricular wall (Storey & Smith, 2012). Importantly, most investigations have reported that the increases in ventricular mass or size in Olympic weightlifters in comparison with sedentary control subjects disappear when normalized for body mass (Storey & Smith, 2012).

SECTION CONCLUSIONS

A key question regarding Olympic weightlifting training is whether the apparent risks outweigh the potential benefits (called the risk-reward ratio). The answer to this question may vary according to the population (Olympic weightlifters, adult athletes, youth athletes, and general population).

As a sport, Olympic weightlifting appears to display a similar risk of injury to other strength sports, such as powerlifting and strongman. Injury incidence in elite Olympic weightlifters during training is around 2.4 – 3.3 injuries per 1,000 hours. Injury prevalence in the competition period is higher, at around 17 – 18% of athletes.

The most commonly-injured parts of the body in Olympic weightlifting are not entirely clear. The low back and knee are probably most frequently injured locations, followed by the shoulder. Olympic weightlifters may also be at a higher risk of developing long-term overuse joint damage at the low back (including spondylolysis) and knee. 

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WEIGHTLIFTING DERIVATIVE TRAINING

INTRODUCTION

Weightlifting derivatives are exercises that are produced when technique modifications are made to the two main lifts (the snatch, and the clean and jerk) but are simpler and less technically difficult to perform, although they are generally performed with lighter absolute loads (Suchomel et al. 2015b). Weightlifting derivatives are less technically difficult than the main Olympic lifts and also typically do not involve placing the bar overhead (power clean, hang clean, high pull, jump shrug, mid-thigh pull). For these reasons, it is usually assumed that they are more commonly-used within athletic development programs than the main Olympic lifts. It is also usually assumed that injury risk is lower than when using the main Olympic lifts. However, while these assumptions are logical, neither has been directly tested. Moreover, very few studies have investigated the effects of a long-term training program using solely weightlifting derivatives on performance measures, such as vertical jump height, or sprint running performance, or even on lower body strength and power, and none have compared the effects with a similar program using the main Olympic lifts. The extent to which weightlifting derivatives can and should replace the main Olympic lifts in an athletic development program is therefore very unclear.

EFFECTS OF WEIGHTLIFTING DERIVATIVE TRAINING

Selection criteria

Population – any healthy population

Intervention – any long-term study assessing the effects of training with weightlifting derivatives

Comparison – baseline

Outcomes – changes in strength, athletic performance measures (sprint running or vertical jumping), weightlifting performance, body composition, and hormone levels

Results

The following relevant studies were identified that met the inclusion criteria: Winchester (2005), Winchester (2009), Otto (2012), Scherfenberg (2013), Sakadjian (2014), Haug (2015a).

Findings

EFFECTS ON WEIGHTLIFTING DERIVATIVE PERFORMANCE

The few investigations that have been performed have reported that long-term periods of training using weightlifting derivatives lead to increases in weightlifting derivative performance, such as 1RM power clean (Otto et al. 2012).

EFFECTS ON LOWER BODY STRENGTH AND POWER

The few investigations that have been performed have reported that long-term periods of training using weightlifting derivatives lead to increases in lower body force production during the power clean (Winchester et al. 2005) and power snatch (Winchester et al. 2009) as well as 1RM back squat (Otto et al. 2012). In addition, gains in peak power output during the power clean (Sakadjian et al. 2014) and vertical jump (Haug et al. 2015a) have been observed.

VERTICAL JUMP HEIGHT

Exploring the effects of a 6-week period of weightlifting derivative training on vertical jump height, Otto et al. (2012) found that countermovement vertical jump height was improved as a result of the training, although the improvements were similar to those produced by kettlebell training. Scherfenberg & Burns (2013) compared the effects of a 6-week period of conventional resistance training with the back squat with a similar training program based on the hang clean. The hang clean group improved vertical jump performance to a greater degree than the back squat group. Haug et al. (2015a) also reported gains in vertical jump height following a hang clean training program in a small group of elite athletes.

BODY COMPOSITION EFFECTS

Exploring the effects of a 6-week period of weightlifting derivative training on body composition, Otto et al. (2012) found no changes in body fat percentage, as measured by skinfolds.

EFFECTS OF IMPROVING TECHNIQUE

Exploring the effect of repeated expert demonstrations on improvements in power clean technique, Sakadjian et al. (2014) found that technique improved faster with the demonstrations compared to a training control group. And although there was no difference in the gains in peak power output between the two groups, linear regression revealed a 22% association between a change in technique and a change in peak power output. Similarly, Haug et al. (2015a) reported that increases in peak power output occurred in tandem with improvements in hang clean technique, although no control group used in this case.

SECTION CONCLUSIONS

Weightlifting derivatives are exercises that are produced when technique modifications are made to the two main lifts (the snatch, and the clean and jerk). They are less technically difficult to perform and are generally performed with lighter absolute loads.

Training with weightlifting derivatives improves weightlifting derivative performance, lower body strength (as measured by 1RM squat and force production), peak power output, and vertical jump height. Frequent expert demonstration may enhance technique improvements and technique improvements are related to gains in peak power output.

Whether weightlifting derivatives are superior to other types of training for any outcome is currently unclear, although preliminary results suggest that they may be better than conventional resistance training for improving vertical jump height, just like Olympic weightlifting.

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WEIGHTLIFTING DERIVATIVE BIOMECHANICS

BACKGROUND

Introduction

Weightlifting derivatives are exercises that are produced when technique modifications are made to the two main lifts (the snatch, and the clean and jerk). They are simpler and less technically difficult to perform, although they are generally performed with lighter absolute loads (Suchomel et al. 2015b). There is a great deal of guidance regarding how they should be taught and performed (Johnson, 1983; Armitage-Johnson, 1994; Graham, 2001; DeWeese et al. 2012; DeWeese et al. 2013; Suchomel et al. 2014c; 2014d). Weightlifting derivatives are very commonly used in athletic training and testing programs for many individual and team sports, including mixed martial arts (Amtmann, 2004), wrestling (Lansky, 1999; Zi-Hong et al. 2013), American football (McGuigan & Winchester, 2008; Nesser et al. 2008; Brechue et al. 2010; Jacobsen et al. 2013), rowing (Lawton et al. 2013), lacrosse (Collins et al. 2014), and rugby (Barr et al. 2014). However, whether weightlifting derivatives like the power clean are an ideal exercise for improving sprint running performance is unclear (Irwin et al. 2007).

TERMINOLOGY

Introduction

The terminology used to refer to weightlifting derivatives can sometimes be confusing. Some coaches use terminology in very strict ways, while others use looser definitions. Overall, most weightlifting derivatives are classified by starting with the main Olympic lift that they most closely resemble (i.e. either the snatch or the clean) and then applying a description of a starting position (hang or mid-thigh) if it is not performed from the ground. In addition, the term “power’ is typically added if the lift is caught without substantial amounts of knee bend. Technically, this provides a strictly-defined battery of weightlifting derivatives as follows: power clean, power snatch, hang clean, hang snatch, hang power clean, and hang power snatch. However, in practice, it is usually assumed that any weightlifting derivative performed from the hang is also a “power” variation and the designation “power” is often therefore omitted (e.g. Suchomel et al. 2014a).

High pull, mid-thigh pull, and jump shrug variations

In addition to the power and hang modifications to the main Olympic lifts, there are also other weightlifting derivatives that are not caught at the top and are therefore not referred to as variations on either the snatch or clean and jerk. The most common of these are the high pull, the mid-thigh pull, and the jump shrug. The high pull is  performed in a similar way to the power clean but is allowed to return to the ground after reaching the top of its trajectory (Waller et al. 2009; Suchomel et al. 2014a; Suchomel et al. 2014c). The jump shrug is held in the hands while jumping and the barbell does not move relative to the body (Suchomel et al. 2014a; Suchomel et al. 2014c). The mid-thigh pull is performed in a similar way to the high pull but is carried out from a set of blocks or a rack that is set at a height corresponding to half-way up the thigh of the (DeWeese et al. 2013). For both the high pull and the mid-thigh pull, there is no catch phase, so there can be no power modification. However, the high pull can be performed either from the ground or from the hang position. The jump shrug cannot be modified with either power or hang variations. Somewhat confusingly, some of these weightlifting derivatives are occasionally referred to as “power clean” variations (e.g. Suchomel et al. 2013; 2014a), which can make it difficult to discern exactly how the exercises investigated are performed at first glance.

THE POWER CLEAN

Selection criteria

Population – any healthy population

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the power clean lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Sewall (1988), Souza (2002a), Souza (2002b), Cormie (2007a), Cormie (2007b), Jones (2008), Comfort (2011a), Comfort (2011b), McBride (2011), Comfort (2012), Hardee (2012), Comfort (2013), Hardee (2013), Moolyk (2013), MacKenzie (2014), Kelly (2014).

Findings

EFFECT OF STARTING HEIGHT

Exploring how the starting height of the lift affected outcomes, Kelly et al. (2014) explored the power clean from the ground and from blocks set at both the knee and mid-thigh. They found that the power clean from the ground displayed a higher absolute load for the 1RM than the knee and mid-thigh positions (93.8 ± 16.5 vs. 87.9 ± 16.9 vs. 85.5 ± 14.2kg).

GROUND REACTION FORCES (GRF)

Exploring the ground reaction force (GRF), Souza & Shimada (2002a) investigated a power clean performed with 60 – 70% of 1RM in young, male weightlifters. They found that the GRF were greatest during the first and second pulls of the clean, but the second pull displayed larger GRF than the first pull. Cormie et al. (2007b) compared the power clean performed with 30 – 90% of 1RM. Peak GRF was greatest with the highest load: 90% of 1RM. Comfort et al. (2012) compared the power clean performed with 30 – 80% of 1RM. Again, peak GRF was greatest with the highest load: 80% of 1RM. However, Comfort et al. (2013) compared the power clean performed with 60 – 80% of 1RM in untrained female athletes and found no differences in GRF between these loads. Exploring the effect of power clean variation on GRF, Comfort et al. (2011a; 2011b) compared the GRF during the power clean, hang power clean, mid-thigh power clean, and mid-thigh clean pull with 60% of 1RM power clean in elite rugby league athletes. They found that GRF was greater in the mid-thigh power clean and mid-thigh clean pull than in the power clean and hang power clean. However, Comfort et al. (2013) compared the power clean, hang power clean, and mid-thigh power clean in untrained female athletes with 60 – 80% of 1RM but found no differences in GRF between variations.

RATE OF FORCE DEVELOPMENT (RFD)

Exploring RFD, Comfort et al. (2011a; 2011b) compared the RFD during the power clean, hang-power clean, mid-thigh power clean, and mid-thigh clean pull with 60% of 1RM power clean in elite rugby league athletes. They found that RFD was greater in the mid-thigh power clean and mid-thigh clean pull than in the power clean and hang power clean. Exploring the effect of load on RFD, Comfort et al. (2012) compared the power clean performed with 30 – 80% of 1RM and found no differences between loads. Similarly, Comfort et al. (2013) compared the power clean performed with 60 – 80% of 1RM in untrained female athletes and also found no differences between loads.

POWER OUTPUT

Exploring power output, Cormie et al. (2007a; 2007b) compared the power clean performed with 30 – 90% of their power clean 1RM. They found that peak power output was greatest at 80% of 1RM. Comfort et al. (2012) compared the power clean performed with 30 – 80% of 1RM. They found that peak power output was measured at 70% of 1RM but there was no significant difference within the range 60 – 80% of 1RM. Similarly, Comfort et al. (2013) compared the power clean performed with 60 – 80% of 1RM in untrained female athletes and found no differences in peak power output within this range of loads. Comfort et al. (2011b) compared the peak power output during the power clean, hang-power clean, mid-thigh power clean, and mid-thigh clean pull with 60% of 1RM power clean in elite rugby league athletes. They found that peak power output was greater in the mid-thigh power clean and mid-thigh clean pull than in the power clean and hang power clean. However, Comfort et al. (2013) compared the power clean, hang power clean, and mid-thigh power clean in untrained female athletes with 60 – 80% of 1RM but found no differences in peak power output between variations.

EFFECT ON KNEE JOINT LOADING

Souza & Shimada (2002a) explored the forces acting on the knee joint during a power clean performed with 60 – 70% of 1RM in young, male weightlifters. At the knee, the compressive forces were large, the anterior forces moderate, and the medio-lateral forces were small. The highest forces were observed in the second pull or the catching phases of the lift.

EFFECT OF INTER-REPETITION REST PERIODS

Assessing the effect of inter-repetition rest period duration, Hardee et al. (2012) compared 3 sets of 6 power cleans with 80% of 1RM with either no rest, 20 seconds, or 40 seconds of rest between repetitions. Peak GRF, power output and velocity all reduced throughout the sets but the reductions were considerably smaller with longer rests. Haff et al. (2003) also examined the effect of using a cluster set format and found that peak velocity and peak vertical displacement were both greater than during a traditional set format. These findings may imply that that taking inter-repetition rest periods may be valuable for improving neuromuscular adaptions relating to lifting heavy loads quickly. Hardee et al. (2013) found that horizontal displacement of the barbell during the power clean was more varied when using either no rest or 40 seconds of rest between sets, while there was no measurable variation in the horizontal displacement of the barbell when using 20 seconds of rest. In addition, vertical displacement was reduced when using no rest but was maintained when using >20 seconds of rest. It was concluded that weightlifting technique (as measured by vertical and horizontal displacement) was maintained constant to the greatest extent when using 20 seconds of rest between repetitions.

EFFECT OF VISUAL FEEDBACK

Exploring the effects of visual feedback Sewall et al. (1988) assessed the effect of practicing in front of a mirror on the power clean movement in individuals with no previous experience. They compared two groups, one which used the mirror to practice and one which did not. Both received basic instruction before practicing. However, both groups displayed alterations in power clean technique as a result of practice.

EFFECT OF EXTERNAL LOADING

Comparing the use of free weight or machine resistance for the power clean performed from the mid-thigh position, Jones et al. (2008) found that 1RM and average power were greater when using free weights but velocity (average and peak) was greater when using the machine loading.

COMPARISON WITH OTHER BALLISTIC EXERCISES

Comparing the power clean with the jump squat using the same absolute loads, MacKenzie et al. (2014) reported that peak GRF was greater in the power clean. However, peak power output was similar across the two exercises. In contrast, when comparing the power clean with the unloaded vertical jump, MacKenzie et al. (2014) reported that peak GRF was greater in the power clean but peak power output was greater in the unloaded vertical jump. Surprisingly, RFD was greater in the power clean than in either the jump squat or the vertical jump. Moolyk et al. (2013) compared the power clean, clean, vertical jump, and drop landing. They found that total lower body work done was highest in the drop landing and clean and lowest in the power clean. For all movements, the knee extensors were the primary contributors to total work done.

Summary

The power clean from the ground uses a heavier load than from blocks placed at the knee or mid-thigh. The power clean involves greater RFD than the jump squat or vertical jump, but less work done than the vertical jump, clean or drop landing.

Peak force and peak power output increase with increasing load, but RFD does not. Peak force, peak power output and RFD are all greater in the mid-thigh power clean and mid-thigh clean pull than in the power clean or hang power clean.

Using short rests between repetitions helps maintain peak GRF, peak power output, peak velocity, and vertical displacement throughout a set. They also reduce variability in horizontal displacement, maintaining consistent technique.

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THE POWER SNATCH

Selection criteria

Population – any healthy population

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the power snatch lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Lauder (2008).

Findings

EFFECT OF EXTERNAL LOADING

Exploring the effect of external loading, Lauder & Lake (2008) compared the biomechanics of the unilateral and bilateral power snatch, by using a barbell and a dumbbell with 80% of 1RM in each case. They noted that there was substantial asymmetry in the GRF and joint angle movements profile of the dumbbell power snatch, which therefore differed from the patterns of the barbell power snatch, indicating that the exercises were performed in different ways and may therefore not produce the same effects.

Summary

The dumbbell power snatch differs from the barbell power snatch insofar as there is substantial asymmetry between sides, both in respect of peak force and joint angle movements.

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THE HANG CLEAN

Selection criteria

Population – any healthy population

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the hang clean or hang power clean lifts

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Kawamori (2005), Hori (2007), Kilduff (2007), Rucci (2010), Lake (2010), Suchomel (2014a), Suchomel (2014b), Suchomel (2014e), Suchomel (2015d).

Findings

EFFECT OF LOAD

Improving peak power output is often a key goal of using weightlifting derivatives, but when studying the hang power clean, Hori et al. (2007) found that the exact method used had a substantial effect on the measurements recorded, indicating that where comparisons are made, the same method must be used in each case. Additionally, Lake et al. (2010) found that there is substantial barbell power output asymmetry, indicating that measurements taken from one side may not correctly report the movement of the center of mass. Nevertheless, Several studies have assessed the effect of load on the hang power clean between 30 – 90% of 1RM in athletic males with experience of weightlifting derivatives (Kawamori et al. 2005; Kilduff et al. 2007; Suchomel et al. 2014a; Suchomel et al. 2014b). Peak GRF is routinely always greatest with the heaviest load (80 – 90% of 1RM), while peak power output is usually highest at a slightly lower load than the maximal load tested (65 – 80% of 1RM), and RFD is not generally affected by load to any great extent. Although peak velocity is less well-studied, linear barbell velocity reduces with increasing load (Suchomel et al. 2014a), as do the angular velocities of the hip, knee and ankle joints (Suchomel et al. 2014e).

COMPARISON WITH OTHER WEIGHTLIFTING DERIVATIVES

Comparing the hang power clean, jump shrug, and high pull, Suchomel et al. (2014a; 2015d) found that the jump shrug produced greater peak power output, peak GRF, and peak velocity than either the hang clean or the high pull, although the force-time curves are similar across the first 80% of the movement (Suchomel et al. 2015d). The high pull also produced greater peak power output and peak velocity than the hang clean. Comparing the hang clean and the jump shrug, Suchomel et al. (2014e) found that the jump shrug involved greater joint angular velocities at the hip, knee and ankle joints, irrespective of load used.

EFFECT OF VISUAL FEEDBACK

Exploring the effect of verbal and visual cues, Rucci & Tomporowski (2010) examined the effects of either visual feedback, verbal cues, or visual feedback plus verbal cues on performance of the hang power clean. They concluded that the visual feedback and visual feedback plus verbal cues conditions were more successful in achieving changes in movement patterns than verbal cues only.

Summary

In the hang power clean, peak force occurs with the heaviest training loads of around 80 – 90% of 1RM, peak power output is achieved with slightly lighter loads, of around 65 – 80% of 1RM. The highest peak linear velocity and joint angular velocities are achieved with the lightest loads.

The hang power clean produces less peak force and power output than other weightlifting derivatives like the jump shrug and high pull. Visual feedback can help improve movement patterns.

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THE HANG SNATCH

Selection criteria

Population – any healthy population

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the hang snatch or hang power snatch lifts

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Canavan (1996), Christ (1996).

Findings

HORIZONTAL DISPLACEMENT

Investigating the horizontal displacement of the bar during the hang power snatch, Christ et al. (1996) compared an elite weightlifter and a resistance-trained individual. They found that the elite weightlifter moved the bar backwards by 10cm in the pull phase, and then moved the bar forwards by 6cm in the unsupported and catch phases. This backward movement during the pull phase may effect a smaller external hip moment arm length and thereby improve efficiency. In contrast, the resistance-trained individual did not move the bar backwards and then forwards, but instead moved the bar slightly backwards in the catch phase.

COMPARISON WITH VERTICAL JUMP

Investigating the biomechanics of the hang power snatch and the vertical jump, Canavan et al. (1996) found close correlations between peak power, time to peak power, peak force, and time to peak force in the two exercises, indicating that they display many kinetic similarities. However, there was no similar close relationship between the two exercises when comparing joint angle movements, indicating a lack of kinematic similarity.

Summary

Hang power snatch technique may differ between elite weightlifters and less well-trained athletes, with more experienced lifters pulling the bar backwards early in the lift before catching it by moving the bar forwards. The hang power snatch is similar kinetically to the vertical jump but the kinematics differ markedly.

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THE JUMP SHRUG

Selection criteria

Population – any healthy population

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the jump shrug lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Suchomel (2013), Suchomel (2014a), Suchomel (2014e), Suchomel (2015a), Suchomel (2015d).

Findings

EFFECT OF LOAD

Assessing the effect of load on the jump shrug in athletic males with experience of weightlifting derivatives, Suchomel et al. (2014a) compared jump shrugs with 30, 45, 65, and 80% of 1RM hang clean. They found that the jump shrug displayed its greatest peak power output with the lowest load used (30% of 1RM hang clean), its greatest peak GRF with a moderately high load (65% of 1RM power hang clean), and its greatest peak velocity with with the lowest load used (30% of 1RM hang power clean). In a similar study, Suchomel et al. (2013) also found that the jump shrug displayed its greatest peak power output and peak velocity with the lowest load used (30% of 1RM hang power clean). However, they did not discern any effect of load on peak force.  In a further similar study, Suchomel et al. (2015a) found that the vertical displacement during the jump shrug, the peak landing force, and the potential energy of the system at peak vertical displacement were all found at the lowest load used (30% of 1RM hang power clean). Suchomel et al. (2014e) compared jump shrugs with 40%, 60%, and 80% of 1RM hang power clean and found that the angular velocities of the hip, knee and ankle joints were highest with the lowest load used (30% of 1RM hang clean).

COMPARISON WITH OTHER WEIGHTLIFTING DERIVATIVES

Comparing the hang clean, jump shrug, and high pull, Suchomel et al. (2014a; 2015d) found that the jump shrug produced greater peak power output, peak GRF, and peak velocity than either the hang clean or the high pull, although the force-time curves are similar across the first 80% of the movement (Suchomel et al. 2015d). Comparing the hang clean and the jump shrug, Suchomel et al. (2014e) found that the jump shrug involved greater joint angular velocities at the hip, knee and ankle joints, irrespective of load used. They suggested that the greater angular velocities might be because the jump shrug is a more ballistic movement that does not involve a catching phase, like the hang clean.

Summary

The jump shrug displays highest peak power outputs, peak velocity, peak joint angular velocities, peak vertical displacement, and peak landing forces with low loads (30 – 40% of 1RM hang power clean). Jump shrugs display greater peak power output, peak force, peak velocity, and peak angular velocities than the hang clean and high pull.

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THE HIGH PULL

Selection criteria

Population – any healthy population

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the high pull lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Suchomel (2014a), Suchomel (2015c).

Findings

EFFECT OF LOAD

Assessing the effect of load on the high pull in athletic males with experience of weightlifting derivatives, Suchomel et al. (2014a) compared high pulls with 30, 45, 65, and 80% of 1RM hang clean. They found that the high pull displayed its greatest peak power output with 45% of 1RM hang clean. In a similar study exploring the hang high pull, Suchomel et al. (2015c) found that peak velocity was maximal when using the lowest load (30% of 1RM hang power clean), peak force was maximal when using the highest load (80% of 1RM hang power clean), and peak power was maximal when using 45% of 1RM hang power clean, in agreement with earlier findings.

COMPARISON WITH OTHER WEIGHTLIFTING DERIVATIVES

Comparing the hang clean, jump shrug, and high pull, Suchomel et al. (2014a; 2015d) found that the jump shrug produced greater peak power output, peak GRF, and peak velocity than either the hang clean or the high pull, although the force-time curves are similar across the first 80% of the movement (Suchomel et al. 2015d). The high pull also produced greater peak power output and peak velocity than the hang clean.

Summary

The high pull and hang high pull displays the highest peak velocity with low loads (30% of 1RM hang power clean), the highest force with high loads (80% of 1RM hang power clean), and the highest peak power with moderate loads (45% of 1RM hang power clean). The high pull displays greater peak power output and peak velocity than the hang clean.

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THE MID-THIGH PULL

Selection criteria

Population – any healthy population

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the mid-thigh pull lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Haff (2005), Kawamori (2006), Khamoui (2011), Comfort (2015).

Findings

RELATIONSHIP WITH OTHER MOVEMENTS

The mid-thigh pull is most commonly used as an isometric test of lower body strength. When used in this capacity, force production in the isometric mid-thigh pull is closely related to Olympic weightlifting performance. In elite female Olympic weightlifters (snatch = 90.8 ? 8.0kg, and clean and jerk = 110.0 ±? 16.0kg), Haff et al. (2005) explored the relationship between the isometric mid-thigh pull and (1) the dynamic mid-thigh pull with a load equivalent to 30% of maximum isometric mid-thigh pull force, and (2) the dynamic mid-thigh pull with 100kg. The relationship between peak force produced in the maximum isometric mid-thigh pull and peak force produced in the two dynamic mid-thigh pull measurements was nearly perfect (r – 0.96 – 0.99). Although Kawamori et al. (2006) performed a similar study and reported strong associations only with heavier loads, this likely indicates that the dynamic mid-thigh pull may be a good exercise for developing greater force production that will transfer to the Olympic lifts.

EFFECT OF LOAD

In order to ascertain the load during the mid-thigh pull that leads to the greatest power output, Comfort et al. (2015) tested 40%, 60%, 80%, 100%, 120%, and 140% of 1RM power clean. They found that peak power, peak bar velocity, and maximum bar displacement occurred with the lowest load tested (40% of 1RM power clean) while peak force and impulse occurred with the highest load tested (140% of 1RM power clean). This suggests that light loads in the mid-thigh pull are best for maximising power outputs, while heavy loads are best for maximising peak force production, as with many other weightlifting derivatives.

Summary

Peak force in the dynamic mid-thigh pull is associated with peak force in the isometric mid-thigh pull, which is closely related to Olympic weightlifting ability.

The dynamic mid-thigh pull may therefore be a good exercise for developing greater force production that will transfer to the Olympic lifts.

Light loads in the mid-thigh pull are best for maximising power outputs (around 40% of 1RM power clean), while heavy loads are best for maximising peak force production (around 140% of 1RM power clean).

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THE PUSH PRESS

Selection criteria

Population – any healthy population

Intervention – any acute study assessing movement-related variables (kinematics) or force-related variables (kinetics) during the push press lift

Comparison – between populations or between exercises

Outcomes – linear displacement or speed, angular rotation or velocity, ground reaction forces, joint moments

Results

The following relevant studies were identified that met the inclusion criteria: Lake (2014).

Findings

RELATIONSHIP WITH OTHER MOVEMENTS

Comparing the push press with the jump squat, Lake et al. (2014) tested the jump squat with 10 – 90% of 1RM back squat and the push press with 10 – 90% of 1RM push press. They found that push press and jump squat peak power and impulse were similar but push press mean power was greater than jump squat mean power.

EFFECT OF LOAD

Assessing the effect of load in the push press, Lake et al. (2014) tested the push press with 10 – 90% of 1RM push press. They found that peak and mean power were each maximized with 75% and 65% of 1RM, respectively.

Summary

Push press peak power output is maximised at 75% of 1RM and is similar to peak power output in the jump squat. Push press mean power output is maximised at 65% of 1RM, and is greater than mean power output in the jump squat.

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SECTION CONCLUSIONS

In weightlifting derivatives, peak force occurs with the heaviest training loads and peak velocity occurs with the lightest training loads. The load at which peak power is achieved differs by exercise variation and is greatest with the heaviest loads in the power clean, moderate-to-heavy loads in the hang power clean and push press, moderate-to-light loads in the high pull, hang high pull and mid-thigh pull, and light loads in the jump shrug.

Peak force and peak power output tend to be greater in the mid-thigh power clean, mid-thigh pull and jump shrug weightlifting derivatives than in the power clean, hang power clean, and high pull. The power clean from the ground uses a heavier load than from blocks placed at the knee or mid-thigh. 

Technique can be enhanced by using short rests between repetitions, which reduce variability in horizontal displacement. Visual feedback can also help improve movement patterns. Technique differs in some weightlifting derivatives between more- and less well-trained weightlifters, with more well-trained lifters pulling the bar backwards early in the lift before catching it by moving the bar forwards. 

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CONTRIBUTORS

Chris Beardsley performed the literature reviews, wrote the first draft of this page and was the primary author.


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