Effect of Physical Education-based stretching programs on hamstring extensibility in high school students: A systematic review

The purpose of the present review was to examine the effects of Physical Education-based stretching programs on hamstring extensibility in high school students. Relevant studies were searched from 10 databases. The results suggested that students should performed stretching programs at least for a duration of 5-6 weeks, a frequency of twice a week, and a volume per session of 30-60 s (20-30 s per set) to obtain improvements on the hamstring extensibility. Stretching programs with higher duration, frequency and volume seems to obtain greater effects. Although the most studies obtained flexibility improvements using static techniques, dynamic stretching exercises performed in a controlled manner also produced improvements and they were safety. After a four-week detraining period, students reverted back to their baseline levels. Teachers should implement stretching programs to improve the students’ flexibility during the Physical Education classes.