A recent experiment by Damasceno et al found that a nice pre-run stretch causes “a reduced capacity of the skeletal muscle to produce explosive force.” As Alex Hutchinson put it for Runner’s World, “I can’t see anything good about something that makes me go slower but feel like I’m trying harder.” Yeah, I’m with Alex: this wasn’t a huge negative effect, but absolutely in the wrong direction. And it’s not like it’s the only evidence of this effect (for instance, Lowery et al showed an 8% drop in performance in a one-mile uphill run, which Alex also wrote about).
This is an extremely popular warm-up ritual, performed with great faith by millions of people, that not only doesn’t help but actually dings performance. That’s an impressive disconnect between belief and reality.
My huge stretching article has been duly updated.