Determining the minimal number of cyclic passive stretch repetitions recommended for an acute increase in an indirect measure of hamstring length

Abstract

The purpose of this study was to determine the minimal number of cyclic passive stretch repetitions required to induce an acute increase in hamstring length via an indirect measure of hamstring length. Eighteen healthy males (aged 19–37 years) were placed in a standardized position. Knee flexion range of motion (ROM) measurements were recorded following ten 15-second passive stretch repetitions. Analysis of variance measures (p<0.05) and post hoc analysis showed that significant increases in knee extension ROM diminished at the fifth stretch repetition. The greatest single increase in knee extension ROM occurred after the first stretch. The results of this study indicate that passive stretching beyond five repetitions results in insignificant gains in hamstring length (measured via knee extension ROM) and are probably unnecessary.