Acute Effects of Practical Hamstring Stretching: Implications for Clinical Practice in the Sports Medicine Setting

Single bouts of stretching can elicit acute transient decreases in strength known as the stretching-induced force deficit. This study examined the acute effects of practical stretching durations on hamstrings strength, work, and power. Forty men and women performed isokinetic leg flexion 60° s-1 and 180° s-1 before and after 2 minutes of stretching. Four experimental groups included static, ballistic, and proprioceptive neuromuscular facilitation (PNF) stretching, and no stretching. Peak torque, peak torque-to-body weight ratio (PTBW), total work, and average power did not change after static or PNF for the men or women. Peak torque, PTBW, and total work decreased after ballistic stretching at 180° s-1 for the men, and average power increased after ballistic stretching a 180° s-1 for the women. Despite mixed results regarding ballistic stretching, practical durations (approximately 2 minutes) of static or PNF stretching for the hamstrings may be incorporated prior to performance events to prevent stretching-induced force deficit