Sprint performance is a critical component to the game of Soccer. Acceleration and speed in soccer are needed to beat opponents and close down opponents in defence. Previous studies have shown that static stretching (SS) can adversely affect maximal speed testing and the sprint performance of highly trained athletes. Dynamic stretching (DS) however, has been found to enhance sprinting ability. In a recent study we conducting, 31 professionals soccer player competing in the English League One were randomly assigned into two groups (static stretching n=16; dynamic stretching n=15). Following a generic 10-minute warm-up players performed three sprints with high tech infrared timing gates recording speed over 20 metres. After two days rest, three further 20m sprint trials were performed immediately following the performance of either static or dynamic stretching of the Gluteals, hip flexors, adductors, quadriceps, hamstrings and gastrocnemius. The static stretching group held each muscle stretch for 20-seconds to the point of mild discomfort, where as the dynamic stretching group completed dynamic moves while maintaining a slow whole body movement. Static stretching resulted in an increase in 20m sprint time of 0.08 seconds. By contrast, dynamic stretching caused a decrease in 20m sprint time of -0.05 seconds. It therefore appears that the use of static stretching within a warm-up routine may have a negative impact upon the sprint performance of professional soccer. In contrast it appears that dynamic stretching elicits performance enhancing benefits. Performance improvements obtained following the dynamic stretching intervention trials are believed to be as a result of an increase in core and/or peripheral muscle temperature. Recommendation: These findings support the importance of incorporating dynamic stretching into the warm-up routine for soccer players and also highlight that static stretching before training and games may have detrimental effects on performance. Stephen Cousins Stephen Cousins is an Exercise Physiology Lecturer at La Trobe University.