A Comparison of Hip Flexibility of Female Collegiate Swimmers and Recreationally Active Non-Swimmers

Abstract

Extensive research has been done on the range of motion and flexibility of the shoulders of swimmers but minimal research has been done on the hip. PURPOSE: The purpose of this study is to compare the hip flexibility between recreationally active non-swimmers and intercollegiate swimmers. METHODS: The subjects were tested using, the passive straight leg raise (PSLR) to measure hip joint range of motion, the sit and reach test (SR) to measure pelvic joint flexibility and a test to measure internal rotation of the hip (IR). Each test was video-taped and analyzed using Dartfish Software to determine maximal range of motion of the joints. RESULTS: Independent t-tests were completed to determine if there was a difference between mean values of non-swimmers and swimmers. Non-swimmers were significantly more flexible with the PSLR (Non-swimmers, 108.7 ± 15.2, Swimmers 97.0 ± 15.6, p < 0.05) and the SR, (Non-swimmers, 111.9 ± 7.4, Swimmers 99.9 ± 7.3 p < .001). There was no significant difference between groups when measuring IR. CONCLUSIONS: An explanation for this is that swimmers are constantly hyper-extended in the lower back to maintain proper stroke form. The freestyle and back stroke swimmers engage in rapid short movements of the hip when performing the flutter kick, this may have lead to the decreased hamstring flexibility measured in the PSLR. Practical application of this information would be that swimmers should train with flexibility exercises to increase the range of motion of the pelvis, hip and lower back to decrease risk of injury and improve overall mobility.