Introduction
Wrestling is one of the oldest combat sports practices that come back to 708 BC in the ancient Greek Olympic Games (6,34,78). Currently, Greco-Roman that is acknowledged as the classic style and freestyle are the 2 internationally recognized forms of competitive wrestling (19). Greco-Roman wrestlers are permitted only to attack and to use their upper body and, then, holds below the waist are forbidden, whereas in freestyle they are permitted to use their whole body during the competition (19). The main objective of each wrestler is to physically dominate an opponent and to establish clear physical control over him/her. Wrestlers compete in a challenging environment involving repetitive bouts of high-intensity actions (e.g., attacks and counterattacks) alternated by submaximal work of low-intensity activity or pause (28,76). Wrestler's physiological demands are complex, requiring athletes to have highly developed capacities of maximal strength, power, muscular endurance, maximal aerobic power, and anaerobic capabilities (28,76). The short quick bursts of maximal power activities during the match are maintained by the anaerobic system, whereas the aerobic system manages the wrestler's ability to maintain effort throughout the duration of the match and accelerates the recovery process within and between successive matches (9,33). As a result, modern wrestling taxes both anaerobic and aerobic energy system with a different level of intervention (9,44,51).
Review articles dealing with physical and physiological characteristics of wrestlers have been published (28,76). The most recent one was published in 2002 (76) and detailed only physiological demands of elite-level male wrestlers without providing detailed information about the difference between sex, age category, weight classes, and wrestling style. Though the review of Horswill (28) was detailed and broadly discussed several parameters related to wrestling performance, the latest article within this review was published in 1991. However, since then many studies were published using more rigorous methodological procedures and materials. Moreover, the changes that occurred in the rules during the last decade (e.g., match duration; judging criteria; weight categories in Olympic Games) may, certainly, influence the physical and physiological demands of the match. For instance, female wrestling has largely grown in popularity since being enrolled into the Olympic Games in 2004 (76,80). This may explain the particular attention made by the scientific community to female wrestlers during the last decade (23,27,32,80). Particularly, establishing a clear understanding of the physical and physiological factors contributing to successful wrestling competition is one of the biggest challenges for coaches and sports scientists (41,44). Thus, providing an extensive up-to-date comprehensive review profiling the physical and physiological attributes of male and female wrestlers in regard to their competitive level, age category, wrestling style, weight classes, and match outcome would help coaches, strength and conditioning professionals, and sport scientists to optimize their training interventions by elaborating scientifically based training programs so as to achieve high performance success. Therefore, the main purpose of the present review was to provide a comprehensive synthesis of the literature and a critical appraisal of the main physical and physiological characteristics of male and female wrestlers from the latest scientific publications.
Methods
Literature Search Strategies
We performed a computerized systematic literature search in PubMed and Google Scholar databases up to August 2016. The following search terms were included: “wrestling,” “wrestling AND physiology,” “wrestling AND physical fitness,” “wrestling AND power,” “wrestling AND strength,” “wrestling AND aerobic,” and “wrestling AND anaerobic.” Furthermore, the reference lists of the included studies were screened to identify additional suitable studies for inclusion in this review.
Selection Criteria
This study was achieved by referring to the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) approach (70). We included studies using (1) elite and amateur, male and female at any age category as participants, (2) detailing aspects of aerobic (maximal oxygen uptake [V̇o2max]), anaerobic (blood lactate concentration [BLC], peak power [PP], and mean power [MP]), and physical (maximal strength, strength endurance, isometric strength, muscular power, and flexibility) parameters of wrestlers. Additionally, all the selected studies should be original investigations written in English language and published in peer-reviewed journals after 1991. Studies not meeting with the aforementioned eligibility criteria were excluded.
Results
Our systematic literature search identified 1,815 potentially relevant studies. A screening of the titles excluded 1,109 studies and then 462 duplicates were removed. The remaining 244 studies were screened based on abstract, and 86 of these were removed. One hundred fifty-eight papers were analyzed concerning the predefined eligibility criteria, and 87 of these were removed. Finally, 71 studies with a total of 2,124 participants (mean sample size 30 subjects) were included in the quantitative synthesis (Figure 1).
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Figure 1.: Flowchart illustrating the different phases of the search and study selection.
Discussion
Aerobic Characteristics
The aerobic energy system is critical to achieve high-level wrestling performance (42,44,73,76). Specifically, the aerobic system contributes to sustain effort throughout the match and to stimulate the recovery process between periods (9,28,56,76) (Table 1). The V̇o2max values reported extend from 37 to 67 ml·kg−1·min−1 and from 39 to 52 ml·kg−1·min−1 for male and female senior wrestlers, respectively (Table 3). For female wrestlers, in particular, there exists limited research studies. When considering cadet male wrestlers, V̇o2max values vary between 42 and 58 ml·kg−1·min−1. The broad range of V̇o2max values established in both men and women seems to be mainly due to the wrestler's level of practice, training phase, mode of testing (i.e., laboratory vs. field and treadmill vs. cycle ergometer) and to the different weight categories. Scientific evidences showed that a cycle ergometer resulted in an 8–10% lower V̇o2max compared with the treadmill test (4,61). The mean values of V̇o2max reported in wrestlers are comparable with those established in karate (47–61 ml·kg−1·min−1 for men) (10), taekwondo (44–63 and 40–51 ml·kg−1·min−1 for men and women, respectively) (8), judo (50–60 and 40–50 ml·kg−1·min−1 for men and women, respectively) (20), and amateur boxing (49–65 and 44–52 ml·kg−1·min−1 for men and women, respectively) (11). These findings mean that wrestling places important demand on aerobic fitness level. Horswill (28) reported V̇o2max values from 52 to 63 ml·kg−1·min−1, similar to the results established in the current investigation. Yoon, (76) revealed that the V̇o2max values of national and international wrestlers were approximately 53–56 ml·kg−1·min−1.
Table 1.: Maximum oxygen uptake of wrestlers (data are presented as mean ± SD).*
Table 1-A.: Maximum oxygen uptake of wrestlers (data are presented as mean ± SD).*
Table 1-B.: Maximum oxygen uptake of wrestlers (data are presented as mean ± SD).*
Table 2.: Lower-body Wingate anaerobic test in wrestlers (data are presented as mean ± SD).*
Table 2-A.: Lower-body Wingate anaerobic test in wrestlers (data are presented as mean ± SD).*
Table 2-B.: Lower-body Wingate anaerobic test in wrestlers (data are presented as mean ± SD).*
Table 2-C.: Lower-body Wingate anaerobic test in wrestlers (data are presented as mean ± SD).*
Table 3.: Upper-body Wingate anaerobic test in wrestlers (data are presented as mean ± SD).*
Table 3-A.: Upper-body Wingate anaerobic test in wrestlers (data are presented as mean ± SD).*
When looking for the difference between wrestlers of various competitive levels, Horswill et al. (29) reported similar V̇o2max values between Olympic, collegiate, and scholastic athletes. However, the recent study of Demirkan et al. (13) reported higher V̇o2max values (11.4–12.5%) in top-elite and elite wrestlers compared with their amateur peers. Yoon (76), Mirzaei et al. (42), and Utter et al. (73) suggested that aerobic metabolism is a basic requirement for elite wrestlers to achieve good performance. Recently, Nikooie et al. (48) reported that successful male wrestlers had higher V̇o2 values corresponding to the ventilatory threshold than their less-successful peers. Altogether, these findings suggest that high level of aerobic power and capacity are important factors to achieve high wrestling performance level.
With respect to female wrestlers, Zi-Hong et al. (80) revealed similar V̇o2max values between successful and less-successful wrestlers. When dealing with the difference between freestyle and Greco-Roman styles, the available research did not show any significant difference between them (15,39). This is consistent with the previous review by Horswill et al. (29). This observation means that the activity of both styles stimulates similarly the aerobic energy system.
Taken together, results indicated that an optimal level of V̇o2max is one of the important factors toward achieving a high wrestling performance level. In view of the paucity of scientific data about female wrestlers, future works are needed. It is worth noting that the activity profile of the presented V̇o2max test is not wrestling specific. For that reason, conducting future studies assessing V̇o2max through a protocol including the particular actions of wrestling are highly recommended.
Anaerobic Characteristics
Anaerobic energy level is critical for judging the final wrestling combat result (23,28,29,45). This is because the determinant moments of the match are mainly associated with the energy provided by the anaerobic energy systems (32). Results of the wrestling mean duration of work and rest periods were 37.2 ± 9.8 and 13.8 ± 6.0 seconds, respectively (∼activity-to-rest ratio: 2.5:1) (49). The latter authors showed high level of BLC (14.8 ± 2.8 mmol·L−1 [6.9–20.6 mmol·L−1]) highlighting the important contribution of the glycolytic system so as to appropriately meet the requirement of wrestling's activity. Horswill (28) and Yoon (76) reported that successful wrestlers are characterized by high-level anaerobic power and capacity in both legs and arms. Mirzaei et al. (44) revealed that with the current change in the international competition rules (3 rounds of 2 minutes with 30 seconds in-between), anaerobic metabolism would be engaged to a larger extent. They noted that the energy provided by anaerobic metabolism sources can be judged as being more critical than the aerobic power and capacity for successful wrestling. To assess wrestlers' anaerobic characteristics, the Wingate anaerobic test has been widely used (13,22,23,39,41,51,57,77). The range of lower-limb PP and MP outputs expressed relatively to the total body-mass of senior/junior elite-level male wrestlers extends from 10 to 17 W·kg−1 and from 4 to 9 W·kg−1, respectively (Table 2). For elite-level senior female wrestlers, the same anaerobic parameters extend from 7 to 9 W·kg−1 for PP and from 4 to 7 W·kg−1 for MP. Results related to PP values within elite-level male wrestlers seem to be higher compared with those established in judo (20), amateur boxing (11), and karate (10). However, with respect to MP output, values recorded within elite-level wrestlers seem to be similar to those established in judo (20), amateur boxing (11), and karate (10). This observation may indicate that elite-level male wrestlers presented a similar anaerobic capacity but a higher anaerobic power compared with the other combat sports athletes. The upper-limb PP and MP outputs range between 7 and 11 W·kg−1 and between 4 and 7 W·kg−1, respectively, for senior/junior elite-level male wrestlers (Table 3). However, studies about the same parameters within elite-level senior/junior female wrestlers are scarce. Hübner-Wozniak et al. (32) revealed that upper-limb PP and MP outputs of Polish elite-level female wrestlers were 5.9 ± 0.5 and 4.6 ± 0.4 W·kg−1, respectively (Table 3). With regard to cadet elite-level male wrestlers, lower-limb PP and MP outputs extend from 8 to 15 W·kg−1 and from 6 to 7 W·kg−1, respectively. The same parameters extend from 8 to 11 W·kg−1 and from 4 to 5 W·kg−1 for upper-limb PP and MP, respectively.
Regarding wrestlers of different competitive levels, results showed higher upper- and lower-limb PP and MP outputs in elite male wrestlers compared with their amateur peers (1,13,16,22,29). Authors attributed this difference to the higher lean body-mass and to the greater neural activation within elite wrestlers. When dealing with studies matching successful and less-successful wrestlers, Roemmich and Frappier (59) reported that the successful wrestlers presented a greater relative anaerobic power (16.5 ± 0.3 W·kg−1) compared with the less-successful ones (15.2 ± 0.4 W·kg−1). The review of Horswill (28) demonstrated that the successful wrestlers presented high anaerobic power and capacity in both upper and lower limbs. Recently, Nikooie et al. (48) revealed that the upper-limb MP was higher in successful elite-level male wrestlers compared with their nonsuccessful counterparts. Authors admit that anaerobic metabolism should be developed as it is one of the most important determinants to Greco-Roman performance success.
Garcia Pallares et al. (23) compared female wrestlers of different competitive levels and revealed that the amateur wrestlers showed lower upper-limb MP and PP compared with the elite ones (17.3–23%). The same observation was recorded when MP and PP values were expressed allometrically (17.8–22.3%). Overall, it seems that the level of anaerobic power and capacity are critical indicators of achieving high-level wrestling performance success.
As expected, heavier wrestlers presented higher absolute arms and leg PP and MP outputs in both genders (13,14,22,39,44,80). However, when normalized to each wrestler's body mass, close values were recorded (13,14,22,39,44). Garcia Pallares et al. (23) reported that upper-limb MP and PP outputs were higher in elite-level middle-weight female wrestlers compared with light-weight ones (15.08–19.2%, respectively). However, when expressed allometrically, no significant differences were detected between the 2 groups, highlighting the effectiveness of this way of performance normalization.
Limited data are available detailing anaerobic level difference between wrestling styles. Demirkan et al. (15) reported higher anaerobic power (14.7% for relative PP) and capacity (9.8% for relative MP) in the upper limbs within elite-level Greco-Roman wrestlers compared with their freestyle counterpart. They attributed this difference to the particular characteristics of the Greco-Roman wrestling style, which requires, essentially, the use of upper-limb technical drills during contests against the opponent. However, Maria Lopez-Gullon et al. (39) revealed that there was no significant difference in arms PP and MP outputs either expressed absolutely or relatively between the 2 styles. This is in agreement with the study of Horswill (28) that reported similar upper-limb PP and MP between the 2 wrestling styles. In view of the disagreement between the aforementioned studies, further studies are needed.
In conclusion, anaerobic power and capacity are important variables for achieving high-level wrestling performance and accurately discriminate between successful and less-successful wrestlers regardless of their age category, weight classes, and wrestling style. Future studies with female wrestlers are recommended. It is worth noting that there is no specific anaerobic test designated to wrestlers as the case of judo (e.g., Special-Judo Fitness Test and Uchi-komi with load test) (2,21,68). Therefore, future investigations studying specific wrestling assessment protocol respecting the activity pattern of the discipline are highly needed.
Strength
Maximal Dynamic Strength
Wrestler's offensive and defensive maneuvers need high level of maximal strength (42,44,51,77). Studies presented in Table 4 have shown that the range of the one-repetition maximal (1RM) values recorded in the squat, bench press, and power-clean exercises extend from 87 to 150 kg, 74–130 kg, and 72–140 kg, respectively, for elite-level male wrestlers. The wide range of values established may be explained by the different competitive level of wrestlers and the weight category's diversity. Wrestling 1RM values seem to be higher than those recorded in taekwondo (8) and karate (10) and similar to the values established in judo (20). This observation denotes higher maximal strength requirement of grappling (i.e., wrestling and judo) combat sports compared with striking ones (i.e., karate and taekwondo). The available research about women (23,80) showed that elite-level wrestlers are stronger than their peers practicing striking combat sports (8).
Table 4.: Maximal dynamic-strength of wrestlers (data are presented as mean ± SD).*
Table 4-A.: Maximal dynamic-strength of wrestlers (data are presented as mean ± SD).*
Table 4-B.: Maximal dynamic-strength of wrestlers (data are presented as mean ± SD).*
With regard to the difference between wrestling styles, the available studies showed that elite-level freestyle wrestlers presented higher absolute maximal strength of arm and trunk extensors compared with Greco-Roman wrestlers (5,66). This observation needs to be reinforced in future research studies.
Mirzaei et al. (42) revealed that elite-level cadet wrestlers of 42 and 46 kg presented a higher relative strength than the other classes. However, Mirzaei et al. (44) studied the physiological profile of elite Iranian junior male wrestlers and revealed that when expressed relatively to body mass, maximal strength values in both bench press and squat exercises were very close between various weight categories. Zi-Hong et al. (80) reported that knee and back absolute isokinetic torque as well as absolute maximal strength were higher for heavier weight classes compared with lighter ones. However, once expressed relative to body mass, this trend was reversed for maximal strength indices with no significant difference for isokinetic exercises. Garcia Pallares et al. (23) reported that 1RM strength was higher in middle-weight elite female group than in light-weight ones (18.3 and 20.1% for squat and bench press, respectively). However, when values of 1RM strength were normalized allometrically, no significant difference was detected between the 2 weight classes. This observation draws attention to the importance of expressing strength performance allometrically.
Upper- and lower-limb maximal strength level is a prerequisite to succeed wrestling performance (28,41,76). This is based on the fact that the major determinant wrestling technical skills intended to lift opponent and to do it, high level of maximal strength is required. Garcia-Pallares et al. (22) detailed physical attributes between male wrestlers of different competitive levels and revealed that elite wrestlers exhibited higher maximal strength expressed either absolutely or relatively (8–25%). The same trend was observed between elite-level and amateur female wrestlers with the former presenting higher (13.4–33.1%) absolute and allometrically scaled values of 1RM strength (23). They refer this outcome to the higher lean body mass within elite-level female wrestlers compared with their amateur counterparts. Morán-Navarro et al. (46) reported that elite-level male wrestlers demonstrated higher maximal strength (bench press: 20% and squat: 22%) normalized to body mass compared with their subelite peers. Zi-Hong et al. (80) reported higher relative and absolute maximal isokinetic torque as well as maximal dynamic strength within the successful compared with less-successful elite-level Chinese female wrestlers. Similarly, Zhang et al. (79) reported that maximal strength and isokinetic torque discriminate between female wrestlers of different competitive successes. The training background has been evidenced to be one of the ultimate aspects for attaining success in both male and female wrestling (22,23,33,65). All these findings are similar to the previous study of Horswill et al. (29) who reported that successful male wrestlers showed higher dynamic and isokinetic strength than their less-successful counterparts. Yoon (76) noted that successful male wrestlers presented higher dynamic and isokinetic strength than unsuccessful wrestlers. Collectively, findings from the above-mentioned research generally indicated that successful wrestlers are stronger in terms of maximal dynamic strength level than unsuccessful wrestlers regardless of sex. In view of the fact that the ability of wrestler to lift and resist opponent's attack is fundamental to perform well in wrestling, wrestlers' maximal strength should be strictly developed as it is a precondition for the development of the other fitness qualities by including a variety of upper- and lower-limb exercises (37).
Isometric Strength
Studies that investigated isometric strength results of wrestlers are in agreements about its critical importance toward achieving high-level wrestling success (Table 5) as it represents one of the most critical components of several wrestling holds (7,23,26,37,39,40,49,59). Values of handgrip strength performance of elite-level male senior/junior wrestlers ranged between 38 and 63 kgf. For cadet male wrestlers, the same performance extends from 31 to 53 kgf. For elite-level female wrestlers, only one study (23) showed that values extend between 27 and 35 kgf. However, future investigations are required to establish more insight about women's hand-grip isometric strength. For lower-back–strength and leg-strength performance, results extend from 114 to 213 kgf and 168 to 272 kgf for elite-level male junior/senior wrestlers, respectively. Results from the available investigations ranged from 122 to 185 kgf and from 165 to 228 kgf for lower-back and leg-strength performance, respectively, within cadet male wrestlers. For female wrestlers, the available investigation (22) revealed values from 85 to 116 kgf across different 8 classes for the lower-back strength.
Table 5.: Maximal isometric strength of wrestlers (data are presented as mean ± SD).*
Table 5-A.: Maximal isometric strength of wrestlers (data are presented as mean ± SD).*
Table 5-B.: Maximal isometric strength of wrestlers (data are presented as mean ± SD).*
Table 5-C.: Maximal isometric strength of wrestlers (data are presented as mean ± SD).*
Roemmich and Frappier (59) revealed higher absolute and relative grip strength of the left (13.3 and 11.1%, respectively) and right (11.3 and 13.6%, respectively) hand in successful wrestlers and concluded that grip strength is one of the most important fitness variables that accurately predict wrestling's performance success as long as it is required to grasp the contestant's lower- and upper-extremities forcefully and manage his/her movement. Garcia-Pallares et al. (22) reported that grip-strength performance of the dominant and nondominant hand indicated higher performance (from 11.6 to 18.6%) for the elite groups compared with the amateur ones in light-, middle-, and heavy-weight classes. Furthermore, elite-level group demonstrated higher relative and absolute back-strength performance (from 9.3 to 20.5%) compared with their lower-level peers. Authors associated this difference with the greater fitness performance, technical, and competitive experience of elite wrestlers compared with nonelite ones. Likewise, the difference in lean mass in favor of elite group seems to explain, in some measure, the higher strength performance level compared with the lower-level wrestlers. Gierczuk et al. (26) stated that high isometric strength level is important to reach high wrestling performance. Demirkan et al. (16) extended previous findings and put forward that a significant difference exists between selected and nonselected male wrestlers (12%) in the back-strength performance. Nikooie et al. (48) reinforced previous findings and stated that both senior and junior successful wrestlers presented a higher grip-strength performance (11.2%) than less-successful wrestlers. The same trend was kept when expressing performance per-kilogram of body mass (13.7%). With the participation of elite-level female wrestlers, Garcia-Pallares et al. (22) extended earlier findings with male wrestlers and reported a greater grip-strength performance in the dominant and nondominant side for the elite groups compared with the amateur one. Similarly, for back-strength performance, elite groups demonstrated higher values than amateur groups. Authors attributed these differences to the higher physical training background for elite wrestlers. Moreover, the greater lean mass within elite-level groups may lead to a higher strength-level production compared with the lower-level groups. In conclusion, it seems that isometric strength level discriminate well between successful and less-successful wrestlers.
Results from the study of Maria Lopez-Gullon et al. (39) demonstrated that Olympic wrestlers from both styles showed similar handgrip strength performance. Similarly, absolute and relative (per-kilogram of fat-free-mass) back-strength values were comparable between Greco-Roman and freestyle wrestlers. Basar et al. (7) reported similar results in both back- and leg-strength between Greco-Roman and freestyle wrestlers. However, when values were normalized per kilogram of lean body mass, freestyle wrestlers demonstrated a greater performance in both tests compared with Greco-Roman wrestlers. The different competition-related demands and the difference in the applied training program may be some of the main reason for isometric strength difference between the 2 styles. In addition, Demirkan et al. (15) reported similar grip- and back-strength results between freestyle and Greco-Roman wrestlers. However, leg strength presented a significant difference between the 2 wrestling styles in favor of the classical style. This may be due to the physical training program difference between the 2 styles. Collectively, it seems that there is no major difference regarding isometric strength performance between both wrestling styles.
In wrestling, athlete's cervical muscles are strongly involved (58,72,75). Essentially, wrestlers need well-developed cervical extensor muscles to counter the opponent's offensive and defensive actions and to maintain the neck and the head in a fixed position against the contestant's force (58). For that reason, many researchers consider improving cervical muscles performance of substantial value for wrestlers (58,72,75). Tsuyama et al. (72) reported that elite wrestlers had higher isometric cervical extension strength at different flexion angles (19–72%) compared with judo athletes. This may be attributed to the higher competition-related demands of wrestlers particularly on their cervical zone when wrestlers, often, try to keep their necks extended to withdraw shoulders from touching the mat. The same observation was recorded for the cross-sectional area of neck extensor muscles, which was also greater in wrestlers compared with judo athletes. Ylinen et al. (75) reported higher isometric cervical extension and flexion strength in Greco-Roman wrestlers compared with nonathletes. Authors revealed, also, a significantly higher isometric flexion strength and rotation strength in senior wrestlers compared with junior wrestlers. This seems to be due to the longer physical training and competition experience of senior wrestlers compared with their junior counterparts (75). In another study detailing the strength of cervical muscle difference between elite wrestlers and nonathletes, Rezasoltani et al. (58) noted that wrestlers presented higher isometric cervical extension and flexion strength than nonathletes. The long-term specific training and competition background of wrestlers compared with nonathletes seems to be the main reason for that result. When comparing wrestling styles, authors revealed that Greco-Roman wrestlers presented a higher cervical muscles strength per kilogram of body mass compared with their freestyle counterparts. Authors attributed this observation to the different training- and competition-related demands between the 2 styles. For instance, Greco-Roman maneuvers and technical skills such as salto (i.e., lifting, returning, and taking down an opponent to the mat from a rear standing position) require a high level of cervical strength. Furthermore, a massive cervical muscles extension force is needed by the wrestler when tacked down to avoid touching the mat by his/her shoulders. Overall, it can be claimed that isometric strength level is one of the most critical factors leading to reach a high-level performance success in wrestling.
Muscle Power
Wrestling match is characterized by sudden explosive attacks and counterattacks to lift opponent powerfully, to bring him/her to the mat and to escape from bottom positions. Such an activity pattern requires a high level of muscular power (13,28,37). Wrestler's muscular power was determined through the use of vertical (i.e., countermovement jump [CMJ]) and horizontal jump (i.e., standing long jump [SLJ]) (Table 6). The mean CMJ values of senior elite-level male wrestlers established in the literature ranged between 47 and 61 cm. The same test performance extends from 33 to 59 cm for junior elite-level male wrestlers. The mean SLJ values for cadet male wrestlers ranged between 196 and 250 cm. For elite-level female wrestlers, the available data (22) suggested similar values compared with other international-level combat sport athletes (8). Male wrestler's performances seem to be higher than those reported in male elite-level taekwondo (8) and karate practitioners (10) and similar to the values recorded within elite-level judo practitioners (20). Furthermore, these values seem to be, even, higher compared with a wide range of sports that count on explosive actions (35,38).
Table 6.: Vertical and horizontal jump performance of wrestlers (data are presented as mean ± SD).*
Table 6-A.: Vertical and horizontal jump performance of wrestlers (data are presented as mean ± SD).*
Starosta et al. (66) and Baić et al. (5) compared wrestling styles and reported a higher explosive-strength, quantified via CMJ, for the freestyle wrestlers. Authors attributed this difference to the greater complexity of freestyle wrestling in terms of using both legs and arms in all techniques used besides the dynamic nature of the activity (i.e., attack-oriented goal) compared to the passive wrestling activity pattern that characterizes the classical style (66). In contrast, Maria Lopez-Gullon et al. (39) revealed no significant difference either in CMJ height and power between the 2 wrestling styles across different weight classes. They concluded that wrestlers from both styles presented similar muscle power level. The difference between the 2 above-mentioned studies seems to be due to the particular fitness features of wrestlers enrolled in each study as well to the difference between wrestling schools (66). However, further investigations are strictly needed to elucidate the difference between both wrestling styles using a more rigorous methodological approach.
Garcia-Pallares et al. (22) compared male wrestlers of different competitive levels and reported that elite-level group in the 3 weight categories (i.e., light, middle, and heavy weight) showed higher CMJ height and power compared with the amateur wrestlers (7.6%–16.6%). Authors associated this difference, in part, to the greater lean mass and neural drive pattern in elite group compared with the amateur one (22). They added, also, that the strength and conditioning training program difference between the 2 groups may explain in some measure this difference. In addition, successful elite-level Greco-Roman male wrestlers showed greater muscle power results (5.6%; insignificant) compared with their less-successful counterparts; however the small sample size (48). In a study conducted with the participation of elite-level female wrestlers, Garcia Pallares et al. (23) demonstrated higher CMJ height in the elite group (2–9%) in comparison with the amateur group. Generally, explosive power is of great importance to be winner in wrestling. Further investigations are required to emphasize the current findings.
Strength Endurance
One of the challenges confronting wrestlers is to maintain high density of competitive actions for an extended period that match the duration of the entire wrestling match (48,69). Such an activity requires high strength-endurance level (36,49,59,69,76). The maximum number of push-ups and sit-ups values per minute ranged between 54 and 70 repetitions and 52 and 77 repetitions for senior/junior elite-level male wrestlers, respectively (Table 7). For pull-ups, the maximum number of repetitions extends from 15 to 50 for senior/junior elite-level male wrestlers. Several studies reported that high muscular endurance is one of the key fitness factors leading to wrestling's performance success (28). Sterkowicz and Starosta (69) noted that training experience significantly influenced performance achievements in the strength-endurance test as higher values were observed in wrestlers of longer training experience (above 9 years) compared with those of average (7–9 years) and shorter training experience (up to 6 years). This finding highlights the importance of the training background on wrestler's muscular endurance level. Likewise, the same authors revealed that the level of expertise (i.e., first class, national class, and international class) affected the strength-endurance performance of arm and trunk muscles, with greater values for the international group compared with the 2 others. Roemmich and Frappier (59) compared successful and less-successful wrestlers and demonstrated higher strength-endurance achievement in successful athletes. Nikooie et al. (48) reported that successful junior wrestlers performed approximately 29% more pull-ups than nonsuccessful ones. The same observation was recorded in senior wrestlers with higher sit-up and pull-up results in successful compared with less-successful wrestlers.
Table 7.: Muscular endurance of wrestlers (data are presented as mean ± SD).*
Table 7-A.: Muscular endurance of wrestlers (data are presented as mean ± SD).*
Table 7-B.: Muscular endurance of wrestlers (data are presented as mean ± SD).*
Few studies examined the strength-endurance difference between wrestling styles. For instance, Starosta et al. (66) and Baić et al. (5) noted that top-level junior freestyle wrestlers expressed significantly higher strength endurance of the trunk and arms muscles compared with Greco-Roman wrestlers. According to the same authors, this difference may be explained by the specific features of each wrestling style. Notably, freestyle wrestling contains higher range of techniques involving both upper and lower extremities compared with the classical style that includes only upper-limb techniques. These particular features of freestyle wrestling require adequate preparation of the trunk and arms muscles that can be developed through long-term physical and technical-tactical wrestling training besides competitions. Unlike the previous studies, Mirzaei et al. (43) reported a better pull-up performance in elite-level Greco-Roman wrestlers compared with the freestyle ones. Although the clear reasons behind the controversial results between the 2 cited studies are hard to establish, it seems that the training background of wrestlers, tests used, muscles groups engaged, and the number of wrestlers involved may contribute to explain these divergent findings.
It is worth noting that studies dealing with strength endurance within female wrestlers are missing. Overall, wrestler's strength endurance is one of the key determinant physical components to achieve wrestling performance success. Further studies detailing strength-endurance difference between Greco-Roman and freestyle wrestling are highly recommended.
Flexibility
Adequate level of flexibility, particularly that of the trunk and legs, is highly needed to perform various wrestling offensive and defensive maneuvers (e.g., lower the center of gravity during defensive position, slip out of disabling and harmful positions, bridge stance, and belly-to-back souple technique in freestyle wrestling) (17,45,54,56,76). The range of sit-and-reach test values extends from 18 to 45 cm for senior/junior elite-level male wrestlers (Table 8). For cadet male wrestlers, values ranged between 20 and 40 cm. For female wrestlers, the available research (23) showed that elite-level Spanish athletes from light- and middle-weight categories demonstrated values around 24 cm in the sit-and-reach test. The range of sit-and-reach test performance of elite-level male wrestlers seems to be higher than that established with senior male international taekwondo athletes (36–36.9 cm) (8). However, these values are similar to those recorded with elite-level judo practitioners (52,62).
Table 8.: Flexibility of wrestler athletes as measured by the sit-and-reach test (data are presented as mean ± SD).*
Table 8-A.: Flexibility of wrestler athletes as measured by the sit-and-reach test (data are presented as mean ± SD).*
Studies about the relationship between wrestling performance level and performance success raised mixed results. For instance, Roemmich and Frappier (59) compared successful and less-successful male amateur-level wrestlers and demonstrated higher flexibility of low-back and hamstrings in the former group. Further, Yoon (76) has denoted that top-level wrestlers showed greater flexibility than those of lower-level ones. However, Garcia-Pallares et al. (22) reported that elite and amateur wrestlers, regardless of their weight categories, demonstrated similar performance in the sit-and-reach test and concluded that flexibility of the hamstring seems to be not related to wrestling performance level. Similarly, Mirzaei et al. (44) revealed similar flexibility performances between different weight classes. Nikooie et al. (48) reported a similar flexibility level measured through the sit-and-reach test in junior and senior successful and less-successful elite-level male wrestlers. Garcia Pallares et al. (23) studied the flexibility difference between elite and amateur female wrestlers from different weight categories and revealed no significant difference between them in accordance with previous findings in male wrestlers (22,48). According to Roemmich and Frappier (59), the discordance between the different studies' results is due to some limitations related to the sit-and-reach test. For instance, it seems that anthropometric parameters (e.g., longer torso or arms) may influence flexibility performance by giving advantages to some subjects. In addition, flexibility is joint specific, and though successful wrestler presented higher flexibility level in the low-back and hamstrings, this observation cannot be generalized to other articulations.
The greater part of the available studies dealing with the flexibility difference using the sit-and-reach test between wrestling styles revealed that there is no significant difference between Greco-Roman and freestyle wrestlers (7,22,39,43) regardless of their weight categories. However, Demirkan et al. (15) reported higher flexibility measured through the sit-and-reach test in freestyle wrestlers (11.8%) compared with their Greco-Roman peers. This difference may be attributed to the particular fitness features of wrestling schools.
Collectively, it seems that flexibility is not a key physical determinant component that leads to reach high-level wrestling success. Future research studies about joint-specific flexibility difference between successful and less-successful wrestlers, elite vs. amateur and Greco-Roman vs. freestyle wrestlers are quite needed.
Practical Applications
From a physiological point of view, the general assessment protocol used demonstrated that an optimal V̇o2max level is one of the important factors toward achieving high wrestling performance level. For that reason, elaborating training programs targeting the cardiorespiratory capacity of wrestlers is crucial. With regard to the wrestler's anaerobic profile, results revealed that anaerobic power and capacity are important variables for achieving high-level wrestling performance and accurately discriminating between successful and less-successful wrestlers regardless of their age category, weight classes, and wrestling style. This particular finding emphasizes the critical importance of developing wrestlers' anaerobic power and capacity. As aerobic power and anaerobic power and capacity are relevant physical abilities to improve wrestling performance, the use of high-intensity interval training seems to be a relevant approach as this kind of training added to the wrestling routine resulted in improvements in all these parameters.
Maximal dynamic strength, isometric strength with a particular attention to the wrestler's cervical muscle zone, explosive strength, and strength endurance are the most critical fitness factors leading to reach high-level performance success in wrestling. Wrestler's flexibility seems not to be one of key physical determinant that help reaching high-level wrestling success. Coaches, strength and conditional specialists, and sport scientists may consult these findings to build-up a comprehensive physical and physiological profile of wrestlers that would assist them in optimizing their training interventions. For an in-depth analysis, future studies should focus particularly on proposing sport-specific assessment leading to an accurate overview of the physical and physiological attributes of wrestlers.
Acknowledgments
No sources of funding were used to assist in the preparation of this review. The authors have no conflicts of interest that are directly relevant to the content of this review.
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