Triple-hop distance as a valid predictor of lower limb strength and power

Context: Hop tests are functional tests that reportedly require strength, power, and postural stability to perform. The extent to which a triple-hop distance (THD) test measures each of these characteristics is relatively unknown. Objective: To determine the extent to which the THD predicts performance on clinical measures of power, strength, and balance in athletic individuals. Design: Within-subjects correlational study. Setting: Station-based, preseason screening of athletes. Patients or Other Participants: Forty National Collegiate Athletic Association Division I-AA men's and women's soccer student-athletes (20 women, 20 men; age = 20.0 +/- 1.4 years, height = 172.8 +/- 9.2 cm, mass = 71.9 +/- 8.9 kg). Intervention(s): As part of a comprehensive preseason screening of athletes, participants completed the Balance Error Scoring System (BESS) test, 3 trials each of the THD and vertical jump, and 5 repetitions each of concentric isokinetic quadriceps and hamstrings strength testing at 60 degrees/s and 180 degrees/s. Bivariate correlations and linear regression analyses determined the extent to which THD (cm) predicted each of the strength, power, and balance measures. Main Outcome Measure(s): Maximal vertical jump height (cm), total BESS error scores, and quadriceps (Quad(60), Quad(180)) and hamstrings (Ham(60), Ham(180)) isokinetic maximum peak torque (Nm) at 60 degrees/s and 180 degrees/s, respectively. Results: Triple-hop distance was a strong predictor of vertical jump height, explaining 69.5% of the variance (P < .01). THD also predicted 56.7% of the variance in Ham(60) (P < .01), 55.5% of the variance in Ham180 (P < .01), 49.0% of the variance in Quad(60) (P < .01), and 58.8% of the variance in Quad(180) (P < .01). No relationships between THD and BESS scores were noted. Conclusions: Triple-hop distance is a useful clinical test to predict an athlete's lower extremity strength and power. Although THD was not a predictor of static balance, further research is needed to examine its relationship with more dynamic balance tests.