RELATIONSHIP BETWEEN FUNCTIONAL MOVEMENT SCREEN AND ATHLETIC PERFORMANCE CHRISTOPHER J. PARCHMANN
AND
JEFFREY M. MCBRIDE
Neuromuscular and Biomechanics Laboratory, Department of Health, Leisure and Exercise Science, Appalachian State University, Boone, North Carolina
ABSTRACT Parchmann, CJ and McBride, JM. Relationship between functional movement screen and athletic performance. J Strength Cond Res 25(12): 3378–3384, 2011—Tests such as the functional movement screen (FMS) and maximal strength (repetition maximum strength [1RM]) have been theorized to assist in predicting athletic performance capabilities. Some data exist concerning 1RM and athletic performance, but very limited data exist concerning the potential ability of FMS to assess athletic performance. The purpose of this investigation was to determine if FMS scores or 1RM is related to athletic performance, specifically in Division I golfers in terms of sprint times, vertical jump (VJ) height, agility T-test times, and club head velocity. Twenty-five National Collegiate Athletic Association Division I golfers (15 men, age = 20.0 6 1.2 years, height = 176.8 6 5.6 cm, body mass = 76.5 6 13.4 kg, squat 1RM = 97.1 6 21.0 kg) (10 women, age = 20.5 6 0.8 years, height = 167.0 6 5.6 cm, body mass = 70.7 6 21.5 kg, squat 1RM = 50.3 6 16.6) performed an FMS, 1RM testing, and field tests common in assessing athletic performance. Athletic performance tests included 10- and 20-m sprint time, VJ height, agility T-test time, and club head velocity. Strength testing included a 1RM back squat. Data for 1RM testing were normalized to body mass for comparisons. Correlations were determined between FMS, 1RMs, and athletic performance tests using Pearson product correlation coefficients (p # 0.05). No significant correlations existed between FMS and 10-m sprint time (r = 20.136), 20-m sprint time (r = 20.107), VJ height (r = 0.249), agility T-test time (r = 20.146), and club head velocity (r = 20.064). The 1RM in the squat was significantly correlated to 10-m sprint time (r = 20.812), 20-m sprint time (r = 20.872), VJ height (r = 0.869), agility T-test time (r = 20.758), and club head velocity (r = 0.805). The lack of relationship suggests that FMS is not an adequate field test and does not relate to any aspect Address correspondence to Jeffrey M McBride,
[email protected]. 25(12)/3378–3384 Journal of Strength and Conditioning Research Ó 2011 National Strength and Conditioning Association
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of athletic performance. Based on the data from this investigation, 1RM squat strength appears to be a good indicator of athletic performance.
KEY WORDS strength, power, sprint, jump INTRODUCTION
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thletic performance tests are commonly used to determine an athlete’s current level of performance, training effectiveness, and to establish norms within a particular sport (4). One factor that has previously been shown to determine sport-specific performance and jumping, sprinting, and agility capabilities has been 1 repetition maximum strength (1RM) (3,6,11,15). Thus, training modifications are often based on measures of 1RM (2). Another possible predictor of sport-specific performance and jumping, sprinting, and agility capabilities has been described as a functional movement screen (FMS) to assess performance in a series of self-described physical activities (unloaded deep squat, hurdle step, in-line lunge, shoulder mobility, active straight leg raise, trunk stability push-up, rotary stability). A 4-point scale (0 = pain was associated with movement pattern, 1 = unable to perform movement pattern, 2 = compensation was present to complete movement pattern, and 3 = movement pattern was performed as described) is used based on the subjective analysis of each movement pattern with specific characteristics listed for each score as reported in Minick et al. (13) and Okada et al. (16). Although 1RM has been shown to relate to jumping and running ability and sportspecific performance, there has been limited investigation concerning the possible relationship of these variables to FMS. Accurate testing for the prediction of possible changes in athletic performance with training or for the identification of exceptional athletes has always been an important factor for the strength and conditioning practitioner. If FMS or 1RM are in fact poor predictors of athletic performance capabilities, then perhaps their use is unnecessary by practitioners. The hypothesis is then that there will not be a significant correlation between FMS scores and 1RM values to 10-m sprint time, 20-m sprint time, vertical jump (VJ) height, agility T-test time, and an example sport-specific skill (club head velocity). As previously mentioned, 1RM has been shown to relate to jumping, sprinting, and agility capabilities, including
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Journal of Strength and Conditioning Research sport-specific skills (3,6,11,15,18). Nuzzo et al. (15) reported a significant correlation between 1RM in the squat and countermovement jump peak power, velocity, and jump height. McBride et al. (11) found significant correlations between 1RM in the squat and 10- and 40-yd sprint times. Wisloff (21) also reported significant correlations between 1RM in the squat and 10- and 30-m sprint times (r = 20.940, r = 20.710). In relation to sport-specific skills, Keogh et al. (6) reported that the 1RM in the back squat was significantly correlated to club head velocity in golfers. The 1RM has also been shown to be related to performance in other sports such as basketball, baseball, tennis, and football (4,5,8,11). For example, increases in strength have been shown to result in increased serve, backhand, and forehand ball velocities in competitive tennis players (8). Strength has also been an indication of proficiency of performance in various sports (4,18). One investigation indicated that leg strength was greater in players who were given more playing time by their coaches in basketball (4). In addition, elite golfers (handicap #0) have been shown to have significantly greater hip and shoulder strength in comparison with subelite golfers (handicap between 1 and 20) (18). Thus, strength and power are factors in golf performance, such as in other sports like tennis and basketball, as indicated by kinetic and kinematic analyses of the golf swing. Previous literature has reported power outputs of 3,875 W (14) in the golf swing in comparison to 3,049 W in jumping (1). The calculated values for rate of force development from Nesbit et al. (14) show a value of approximately 7,550 Ns21 in comparison to a VJ value of 2,012 Ns21 (1). Hip and torso torque during the golf swing have been reported to be approximately 200 Nm (10) in comparison with hip torque during sprinting of 232 Nm (17). The previous literature then indicates that 1RM may be a good indication of the overall performance in a variety of athletes including golfers; therefore, the testing of 1RM and FMS in this investigation involved golfers who depend on strength and power variables for increased performance. As mentioned above, FMS involves a process of scoring performance in a series of self-described physical activities using a 4-point scale based on the subjective analysis of each movement pattern with specific characteristics listed for each score as reported in Minick et al. (13) and Okada et al. (16). This scoring procedure has been reported to have a high interreliability among testing personnel for each test ranging from 0.74 to 1.00 (13). The 7 movement patterns are claimed to be conceptualized on the basis of the complex movement patterns found in sport such as jumping, running, and agility (13). Okada et al. (16) investigated the relationship between FMS scores and performance in a medicine ball throw, an agility T-test and a single leg squat. There were significant but modest correlations between these variables (r = 0.300– 0.500). The FMS scores have also been shown to improve
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through a specific training program conducted by Kiesel et al. (7), but no other known investigations have examined FMS and its possible relationship to athletic performance It appears that 1RM squat and FMS may have some relationship to athletic performance. However, to our knowledge, no investigation has compared the 2 types of evaluation (1RM squat, FMS) with variables such as sprinting, jumping, and agility performance in a single study. In addition, no investigations have examined the relationship between the 1RM squat or FMS and sport-specific performance such as club head velocity in competitive golfers. Thus, the purpose of the current investigation was to determine if the 1RM squat or FMS was related to jumping, sprinting, and agility capabilities and a sport-specific skill (club head velocity) in competitive golfers. The analysis of these assessment tools might determine the efficacy of their use in strength and conditioning programs.
METHODS Experimental Approach to the Problem
This study was designed to determine if the 1RM squat or FMS was related to athletic performance. Several studies have suggested strength testing to be an effective portrayal of athletic ability (3,6,11,15,18). Evidence surrounding the use of FMS as a predictor of athletic performance is limited. Thus, a 1RM squat, FMS scores, 10-m sprint time, 20-m sprint time, VJ height, and T-test completion time were measured and Pearson product correlation coefficients calculated between selected variables. These measurements will assist in determining if 1RM or FMS can be used for the prediction of sport-specific performance. Subjects
Twenty-five National Collegiate Athletic Association (NCAA) Division I golfers (15 men, age = 20.0 6 1.2 years, height = 176.8 6 5.6 cm, body mass = 76.5 6 13.4 kg, 1RM back squat = 97.1 6 21.0 kg) (10 women, age = 20.5 6 0.8 years, height = 167.0 6 5.6 cm, body mass = 70.7 6 21.5 kg, 1RM back squat = 50.3 6 16.6 kg) participated voluntarily in this investigation. Criteria included participation in the NCAA Division I team and no existing injury. The subjects were tested from December to February in the off-season and were involved in a 2-year strength and conditioning training program developed by the investigator. The subjects were asked to refrain from any physical activity training 24 hours before testing. The subjects were informed of the testing procedures and were required to sign an informed consent preceding testing. Approval from the Appalachian State University Institutional Review Board was obtained before the start of the investigation. Study Design
The subjects participated in 3 sessions that included height, body mass, FMS, strength testing, and field tests that are common in assessing athletic performance (3,5,12). Strength testing included a 1 repetition maximum squat (1RM). The VOLUME 25 | NUMBER 12 | DECEMBER 2011 |
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Functional Movement Screen
Figure 1. Correlation between the FMS score (0–21) and 10-m sprint time (seconds) and correlation between 1 repetition maximum in the squat relative to body mass (1RM/BM) and 10-m sprint time (seconds). *Significant at p # 0.05.
athletic performance tests included 10- and 20-m sprint time (10mSP and 20mSP), VJ, T-test completion time (TT), and club head swing velocity (CHSV). The testing sessions were separated by at least 24 hours. The procedures of each performance test were verbally explained and demonstrated during the beginning of each testing session. In session 1, the subjects were measured for height and body mass and then tested in FMS, 10mSP, 20mSP, VJ, and TT. In session 2, the subjects were tested for a 1RM. In session 3, CHSV was tested. Functional Movement Screen
The FMS used 7 movements and 3 clearing examinations as described by Minick et al. (13) and Okada et al. (16) to assess functional movement. Each of the 7 movements was scored from 0 to 3. The greatest score one could achieve was a 21. The same investigator scored all the FMS tests. The investigator has
worked and trained with personnel proficient in FMS in the private industry. The investigator has tested .100 general population subjects and .50 athletes using the FMS technique. The total FMS score was used for comparisons, which could range from 0 to 21. One Repetition Maximum Testing
Strength testing was based on methods previously used by McBride et al. (11) using a free weight barbell back squat. Two warm-up sets between 2 and 5 repetitions at approximately 50% and 80% of the subjects perceived 1RM were first performed. Warm-up sets were separated by a 1-minute rest interval. Attempts were then performed until a 1RM was achieved. Three to five minutes of rest was given between 1RM attempts to allow for full recovery. The same investigator judged successful 1RM attempts based on visualization of the top of the thigh ensuring that it was
Figure 2. Correlation between the FMS score (0–21) and 20-m sprint time (seconds) and correlation between 1 repetition maximum in the squat relative to body mass (1RM/BM) and 20-m sprint time (seconds). *Significant at p # 0.05.
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Figure 3. Correlation between the FMS score (0–21) and vertical jump height (centimeters) and correlation between 1 repetition maximum in the squat relative to body mass (1RM/BM) and vertical jump height (centimeters). *Significant at p # 0.05.
parallel to the floor indicated. Relative strength values were used for analyses. Relative strength values were calculated by dividing the 1RM measured in kilograms by subjects’ body mass measured in kilograms. Vertical Jump Testing
The VJ height was tested as an indicator of hip and leg power. The subjects performed 3 countermovement VJs, and the best of the 3 VJs was used for analyses. Each VJ began with both hands at eye level; knees unlocked, and used a 2-foot take-off with no approach steps permitted. The subject moved into a semisquat position while swinging the arms back preparing for the jump. The arms swung forward above the head as the subject jumped vertically into the air. The subjects returned to the ground with both feet landing at the same time with the ankle plantar flexed. Jump performance was assessed using a Just Jump System (Probotics, Huntsville, AL, USA) VJ testing mat (9).
Sprint Protocol (10mSP, 20mSP)
Ten and 20-m sprint times were performed on a standard track surface from a standing start using an infrared timing system (Brower Timing Systems, Draper, UT, USA). Timing gates were placed at both the 10- and 20-m mark. The time was manually started at the first sign of movement. The same investigator was used to start each sprint to increase reliability. Three- to five-minute rest intervals were taken to allow for full recovery. The best of 3 maximal sprint trials was used for analyses (11). Agility T-test
The T-test was used to assess agility. The subject began from a standing start behind a cone that marked the starting and finish line. The subject then sprinted forward in a straight line and was required to touch a cone positioned 10 yd away. The subject then side shuffled and touched a cone positioned 5 yd
Figure 4. Correlation between the FMS score (0–21) and agility T-test time (seconds) and correlation between 1 repetition maximum in the squat relative to body mass (1RM/BM) and agility T-test time (seconds). *Significant at p # 0.05.
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Functional Movement Screen
Figure 5. Correlation between the FMS score (0–21) and club head velocity (meters per second) and correlation between 1 repetition maximum in the squat relative to body mass (1RM/BM) and club head velocity (meters per second). *Significant at p # 0.05.
to the left. The subject then side shuffled to the right and touched a cone placed 10 yd away. The subject then side shuffled 5 yd to the left back to the cone directly vertically from the starting cone. The subject then back pedaled 10 yd through the finish line where the test began. The test began when the investigator verbally signaled to start. Upon signaling, the investigator manually started a stop watch. During side shuffling, the subject always faced the same direction and was not allowed to cross the feet. A trial was invalid if the feet crossed or the cone was not touched. Three- to five-minute rest intervals were taken between trials to allow for full recovery. The best of 3 maximal effort trials was used for analyses (12).
between FMS and any of the other performance variables as well (10mSP, 20mSP, VJ, TT). The 1RM was significantly correlated to CHSV (r = 0.805, p = 0.0001). The 1RM was also significantly correlated to VJ (r = 0.869, p = 0.0001), 10mSP (r = 20.812, p = 0.0001), 20mSP (r = 20.872, p = 0.0001), and TT (r = 20.758, p = 0.0001). The FMS score from each individual test (unloaded deep squat, hurdle step, in-line lunge, shoulder mobility, active straight leg raise, trunk stability push-up, rotary stability) were also compared with 10mSP, 20mSP, VJ, TT, and CHSV. No significant relationships existed between any of the individual test and the athletic performance tests.
Club Head Swing Velocity
DISCUSSION
Club head swing velocity was tested at an indoor practice facility. The subjects warmed up by taking several practice swings with their own driver. The CHSV was tested while the subjects used their driver to hit the same brand, regulation sized balls, off a tee from an Astroturf Ó mat into a practice net. Each subject was given 5 swings, and the best club head speed was used for statistical analyses. The CHSV data were collected using a Zelocity PureLaunch Tracker Launch Monitor (Zelocity Corp., Scottsdale, AZ, USA) connected to a laptop computer (19). Statistical Analyses
Male and female groups were combined for data analyses. Data were analyzed with descriptive statistics, and the results were reported as mean 6 SD. The FMS and 1RM were correlated to athletic performance tests (10mSP, 20mSP, VJ, TT, CHSV) using a Pearson product-moment coefficient, and significance was indicated as p # 0.05. All statistical analyses were performed using SPSS Version 17.0 (SPSS Inc., Chicago, IL, USA).
RESULTS There was no correlation between FMS and CHSV (r = 20.064, p = 0.760). No significant correlations were found
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The primary finding in this investigation was that the FMS score had no significant relationship to sprinting, jumping, or agility performance. In addition, the FMS score had no significant relationship to sport-specific performance (club head velocity). In contrast, the 1RM in the squat had strong significant relationships to all variables measured. The current investigation is supported by previous studies in terms of the relationship between 1RM and athletic performance variables (2–4). Only one other investigation has reported the relationship between FMS and the medicine ball throw, an agility T-test and a single leg squat (16). This investigation contradicts the findings from Okada et al. (16) in that no significant relationships were observed concerning the FMS score to any athletic performance variable. The investigators in the current investigation scored each subject based on the previously described process by Okada et al. (16). The total FMS score (which can range from 0 to 21) was used for the correlations and for the individual physical activities (unloaded deep squat, hurdle step, in-line lunge, shoulder mobility, active straight leg raise, trunk stability push-up, rotary stability). Neither the total score nor the individual physical activities significantly correlated to
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Journal of Strength and Conditioning Research any of the athletic performance tests (sprinting, jumping, agility, or club head velocity). In the investigation by Okada et al. (16), only correlations of the individual evaluative physical activities to the medicine ball throw, agility T-test, and a single leg squat were reported. Correlations reported (16) were random in nature. For example, right shoulder mobility was reported to be significantly correlated to the medicine ball throw (r = 20.388) but not left shoulder mobility (r = 20.055). Left leg in-line lunge and right shoulder mobility were correlated to the agility T-test (r = 20.462, r = 0.392) but no other FMS physical activity scores. Right shoulder mobility, as previously mentioned, was negatively correlated to the medicine ball throw distance (r = 20.388). This would indicate that a higher FMS score in the right shoulder mobility was associated with a smaller distance in the medicine ball throw, meaning that greater right shoulder mobility resulted in a poorer performance. The correlation between right shoulder mobility and agility T-test time to completion was positive (r = 0.392). Indicating that the higher the FMS score, the slower the subject completed the T-test. The FMS score for the left in-line lunge was negatively correlated to the agility T-test time to completion (r = 20.462), indicating that a higher FMS score was related again to a slower time to completion in the T-test. Thus, most of the significant correlations between FMS and athletic performance variables indicated that a higher FMS score was related to a poorer level of performance. In this study, there were no significant correlations between FMS score and 10-m sprint time (r = 20.136), 20-m sprint time (r = 20.107), VJ height (r = 0.249), or club head velocity (r = 20.064). In contrast, squat strength (1RM) had a very strong relationship to athletic performance in this study, and this is supported by subsequent investigations (3,4,6,8,11,18,20). The lack of relationship of FMS scores to athletic ability may be founded in that none of the physical activity tests actually assess the strength (1RM) of the athlete. The squat strength (1RM) in this study was significantly correlated to the 10-m sprint time (r = 20.812), 20-m sprint time (r = 20.872), VJ height (r = 0.869), and club head velocity (r = 0.805). As previously mentioned, in other investigations, the 1RM in the squat has been shown to relate to countermovement jump peak power, velocity, and jump height and sprinting capability (11,21). In addition, previous studies have indicated a relationship to club head velocity in golfers, and increases in strength have been shown to result in increased serve, backhand, and forehand ball velocity in tennis players (6,8). Proficiency in sport, as well, can be related to 1RM, as reported in golf and basketball (4,18). Thus, it can be concluded based on the study by Okada et al. (16) and this study that the total FMS score or individual physical activity FMS scores do not relate to any athletic performance variables in a positive sense. In fact, data from Okada et al. (16) showed several times that higher FMS scores actually related to a poorer athletic performance. In
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contrast, based on previous data and data from the current investigation, the 1RM is a very effective variable to assess athletic performance capabilities.
PRACTICAL APPLICATIONS Based on the data from the current investigation, the FMS is not a useful tool for determining possible athletic capabilities, specifically in golf. In fact, higher FMS scores may falsely lead a practitioner to assume increased athletic capabilities when in actuality higher scores relate to poorer performances in tests such as the medicine ball throw or agility T-test times. The squat 1RM was a very strong predictor of athletic performance such as sprinting, jumping, and agility performance. It is likely that the FMS fails to relate to athletic performance in that it does not assess strength, which has been shown to be a major component of athletic performance. In conclusion, FMS should not be used to assess athletes and strength and conditioning coaches should use 1RM squat determination as a very important assessment tool as a component for the determination of athletic performance.
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