Maximum Sprints Elicit Higher Peak Knee Joint Power than Resistance Training Exercises.

BACKGROUND: Sprinting places exceptionally large mechanical demands on the knee flexors, particularly during the late swing phase when the hamstrings are actively lengthened under load. Therefore, coaches and practitioners try to increase the hamstrings' capacity to absorb energy by various resistance training exercises with high (supramaximal) eccentric intensity. However, it is unclear whether the load parameters are equivalent to maximum sprints. Consequently, the aim of this short study was to compare peak knee power values derived from aggregated previously published datasets of maximum sprints and strenuous hamstring exercises, rather than from a single directly controlled experimental comparison.

METHODS: Previously published inverse dynamic analyses of sprints, explosive Razor Curls, decelerated Nordic Hamstring Exercise and eccentric isokinetic hamstring tests were aggregated and compared.

RESULTS: The combined data showed that both absolute and relative peak knee power were 8 to 14 times higher during sprinting at 10 m/s-primarily due to 6- to 14-fold higher knee extension angular velocities.

CONCLUSIONS: Peak knee power during maximum sprints was not replicated by the analyzed hamstring exercise conditions, even if they were very explosive and strenuous.