Hip Strength Changes in Collegiate Soccer Athletes Across A Competitive Season

Hip strength has previously been correlated with injury, but there is limited evidence on the changes in hip strength across a competitive season. PURPOSE: To determine the changes to hip strength across a competitive season in male and female soccer athletes. METHODS: Fifty-five soccer athletes (28 M, 27F, age = 20.7 ± 1.6 years, height = 173.6 ± 8.3 cm, mass = 72.2 ± 8.1 kg) performed strength assessments of the hip abductors and hip adductors at preseason, midseason, and postseason time points. Isometric hip strength was collected in a supine position with the knees bent to 90 degrees and hips flexed to 45 degrees. Three trials of hip abduction and hip adduction were performed on the right and left legs. Forces were standardized to body weight of the individuals, and the average force per bodyweight (%BW) of the trials was used for analysis. Linear mixed models were used to determine the differences in hip adduction and abduction between sex (male and female) and time of year (preseason, midseason, postseason). Limb was included in the analysis as a covariate and the participant was used as a random intercept. Post-hoc testing was performed with t-tests. Analysis was significant when p < 0.05. RESULTS: There was no interaction between sex and time (p > 0.05) for any analyses. For hip abduction, there was a significant main effect of time (F = 8.49, p < 0.001) and sex (F = 8.05, p = 0.006). Female athletes demonstrated a 6.2%BW lower hip abduction force than male athletes (p = 0.006), and there was a 1.6%BW decrease in strength at the postseason time compared to the midseason time (p = 0.004). For hip adduction, there was a significant main effect of time (F = 8.43, p < 0.001). There was a 2.3%BW decrease in hip adduction at postseason compared to midseason (p = 0.001). CONCLUSIONS: Hip strength significantly differs between sexes when accounting for bodyweight, and there is a significant change throughout the season. Due to female athletes’ higher injury rates, hip abduction and adduction should be targeted with interventions to ensure these variables do not contribute to their injury risk. Additionally, the variability throughout the season indicates that hip adduction and abduction should be monitored to track strength changes.