Pre-exercise static stretching can hinder performance- do you agree?

Once upon a time, pre-exercise static stretching was the norm. However, in the last few years, research has shown that stretching a muscle before very high-intensity activity such as sprinting or weight lifting is actually disadvantageous. This is because static stretching temporarily breaks some of the chemical bonds involved in the contraction process within muscle filaments, and therefore the ability of the muscle fibres to contract maximally. Until recently, this effect was not assumed to be significant for endurance activities, where the force of muscle contraction is not maximal. However, new research by US scientists suggests that this assumption may be erroneous.

In the study, the researchers investigated the effects of static stretching on energy cost and endurance performance in ten trained male runners (average age 25 years, average VO2max 63.8mls/kg/min). The subjects underwent three separate days of testing; on day 1, body measurements and VO2max were measured. On days 2 and 3, the subjects randomly performed a 60-minute treadmill run under stretching or non-stretching conditions separated by at least one week. The stretching routine consisted of 16 minutes of static stretching using five exercises for the major lower body muscle groups, whereas non-stretching consisted of 16 minutes of quiet sitting. The run consisted of 30 minutes at 65% of VO2max followed by a 30-minute performance run where participants ran as far as possible without viewing distance or speed. Total calories expended were determined for the 30-minute preload run, whereas performance was measured as the distance covered in the performance run.

The results showed that performance was significantly greater in the non-stretching trial. Subjects covered an average of 6.0km when they didn’t stretch and only 5.8km when they did. Moreover, the runners expended significantly more energy during the stretching condition compared with when they didn’t stretch (425 vs. 405Kcals) indicating that the muscles were working less efficiently when they were stretched prior to exercise. The researchers concluded that static stretching before an endurance event may lower endurance performance and increase the energy cost of running, and these findings have obvious implications for all endurance sportsmen and women.

What do you think about this?

Has this been the case from your experience?