Sugiura Y, Saito T, Sakuraba K, Sakuma K, Suzuki E
In this prospective cohort study of elite sprinters, muscle strength of the hip extensors, as well as of the knee extensors and flexors, was measured to determine a possible relationship between strength deficits and subsequent hamstring injury within 12 months of testing. Hamstring injury occurred in 6 subjects during the 1-year period. Isokinetic testing at a speed of 60 degrees /s revealed weakness of the injured limb with eccentric action of the hamstring muscles and during concentric action of the hip extensors. When performing a side-to-side comparison for the injured sprinters, the hamstring injury always occurred on the weaker side. Differences in the hamstrings-quadriceps and hip extensors-quadriceps strength ratios were also evident between uninjured and injured limbs, and this was attributable to deficits in hamstring strength.
Hamstring injury in elite sprinters was associated with weakness during eccentric action of the hamstrings and weakness during concentric action of the hip extensors, but only when tested at the slower speed of 60 degrees /s
Journal of Orthopaedic and Sports Physical Therapy, 2008, 38(8), 457-64