USA Track and Field, the governing body of the sport in the USA, is launching a study to determine the effectiveness of pre-run stretching on injury prevention. You can participate. From the USATF web site:
USATF is conducting a study to determine the effect of pre-run stretching on running injuries. The purpose of the study is to determine specifically if pre-run stretching of the three major leg muscle groups is beneficial for overall injury prevention or reduction. The study is not examining in-run or post-run stretching.
The stretches under study involve quadriceps, hamstrings, and achilles/calf. There has been considerable discussion in recent years in the running community regarding the efficacy of stretching. There are those who swear by it and those who swear at it. Personally, I don’t like to stretch right before a run and certainly not immediately before a race. Instead, I have found light calisthenics and easy jogging to be preferable. I do a bit (maybe 20 to 30 minutes) of yoga-based stretching every morning to maintain range of motion, but that’s outside of my running. I also find some light post-run stretching to be effective. The worst advice I have ever received is to stretch an injured muscle/joint. My experience is that this only does further damage and that stretching an injured area should only begin once the area has begun to heal, and the stretching should be very modest initially.
The results of the USATF will be interesting, and no doubt start some lively debate on the running boards.