Association Between Ankle Range Of Motion And Anaerobic Sprint Test Performance In American Professional Soccer

Soccer is an intermittent and high intensity sport which demands a high level of aerobic and anaerobic activity. The Running Anaerobic Sprint Test (RAST) is a common test performed to evaluate anaerobic power and capacity. Previous research in youth soccer players has suggested that functional measurements may not determine physical performance well. However, it is unknown how functional measurements such as ankle range of motion (ROM) influence the RAST test in professional soccer players. PURPOSE: The purpose of this study was to examine the relationship between static ankle ROM and anaerobic relative peak power. METHODS: Fifteen male United Soccer League (USL1) players completed the testing. The RAST was performed outdoors following the warmup phase of a preseason practice. This test consisted of six max effort 35 m sprints with 10 seconds of passive recovery between each sprint. Relative peak power was calculated for each player. Static dorsiflexion ROM was obtained for both the dominant and nondominant limbs using the weightbearing lunge test. Bivariate correlations were used to assess the relationship between power and ROM with an a priori alpha level of 0.05. RESULTS: Bivariate correlation results suggested a significant inverse relationship between peak power and the dominant limb ROM (r = -0.67, p = 0.003) and the nondominant limb (r = -0.61, p = 0.009). These analyses suggest that as dorsiflexion ROM increases, relative peak power decreases in both the dominant and nondominant limbs. CONCLUSIONS: The current findings corroborate previous research on elite youth soccer players. Previous reports provide little evidence of the association between functional movement screen scores and physical performance. Indeed, our findings show that greater ankle ROM was associated with decreased power during the RAST. Further, previous studies correlated high ankle stiffness with increased ground reaction forces, velocity, and efficiency in sprinting. This may explain the inverse relationship we observed. Sports science teams should work with coaching staff in an attempt maximize anaerobic power, while also minimizing injury risk.