Duration of maintained hamstring flexibility after cessation of an acute static stretching protocol

Area of Science:

• Kinesiology
• Sports Medicine
• Rehabilitation Science

Background:

• Static stretching is widely recognized for enhancing muscle flexibility.
• Limited research exists on the duration of flexibility gains from same-day static stretching, particularly for hamstring flexibility and knee joint range of motion.

Purpose of the Study:

• To determine the duration of maintained hamstring flexibility gains after an acute static stretching protocol.
• To measure changes in knee joint range of motion using an active knee-extension test.

Main Methods:

• Thirty male subjects with limited hamstring flexibility were randomly assigned to a control or experimental group.
• The experimental group performed 4 sets of 30-second static hamstring stretches with 15-second rests.
• Active knee-extension measurements were taken at baseline and at 1, 3, 6, 9, 15, and 30 minutes post-stretching.

Main Results:

• The experimental group showed a significant improvement in knee-extension range of motion immediately after stretching.
• These flexibility gains were statistically significant for 3 minutes post-stretching.
• No significant difference from baseline was observed in measurements taken after 3 minutes.

Conclusions:

• Four consecutive 30-second static hamstring stretches temporarily enhance flexibility, as indicated by increased knee-extension range of motion.
• The positive effects on hamstring flexibility were short-lived, lasting only 3 minutes after the cessation of stretching.
• Further investigation into different stretching modalities is recommended to achieve longer-lasting flexibility improvements.