We humans have an inclination that, if we hear something over and over, it must be true. And we have heard for years that stretching prevents injuries and improves performance. So we continue to lower our heels over a step to stretch our calves, or try for the thousandth time to reach our toes before a run. Stand at the st
art line of the Bolder Boulder and you will witness at least half the racers doing some last minute hamstring stretches. But that hamstring stretch might just cost them the race.
Flexibility is overrated, and it can slow you down. That’s right, up to a point, tighter is faster. The runners with the tightest hamstrings tend to be the most efficient and the fastest. That’s because tighter muscles have greater elastic energy storage than loose, limp muscles.
A 2010 study of ten collegiate male athletes showed that static stretching before a one hour run caused a significant decline in performance. Other studies corroborate this point. Stretching before exercise decreases muscle strength by as much as 30%. Why? Because our brains are wired to protect us, when we perform a sustained stretch the nervous system goes into protective mode and inhibits the stretched muscle to keep it from tearing.
So if stretching does not improve performance, at least it will keep you from being injured, right? Wrong. At least not in the way we usually stretch — bent over, trying like crazy to reach your toes. Several large scale studies have shown no difference in injuries or rep
orts of pain for those who stretch versus those who don’t. Besides, does that 30-second stretch before you jog actually loosen you up over time? No again. You would need at least an hour of stretching daily to make a difference. Even then, there’s no guarantee it will help you avoid an injury.
In her book, The First Twenty Minutes, Gretchen Reynolds debunks many exercise myths that have athletes continuing to do the craziest things in spite of what science tells them. So, if you are now wondering what to do in those interminably long moments before a race, try this. Walk briskly for a few minutes to increase blood flow to your legs. Do some linked squats and lunges. Try kicking your buttocks with your heels to wake up your quads. Bounce around on your toes to alert the calves. Dynamic warm-ups heat up the muscles and excite them, so they are ready to work when you need them. Watch this video and be ready for your next race. 
