Acute effects of static and dynamic stretching on hamstrings' response times

The main purposes of this study were to (a) investigate acute effects of static and dynamic lower limb stretching routines on total response time, pre-motor time and motor time of the medial and lateral hamstrings during maximal eccentric isokinetic knee flexion; and (b) determine whether static and dynamic routines elicit similar responses. A total of 38 active adults completed the following intervention protocols in a randomised order on separate days: (a) non-stretching (control condition), (b) static stretching and (c) dynamic stretching. After the stretching or control intervention, total response time, pre-motor time and motor time of the medial and lateral hamstrings were assessed during eccentric knee flexion movements with participants prone. Measures were compared via a mixed-design factorial ANOVA. There were no main effects for total response time, pre-motor time and motor time. The results suggest that dynamic and static stretching has no influence on hamstrings response times (total response time, pre-motor time and motor time) and hence neither form of stretching reduces this primary risk factor for anterior cruciate ligament injury.