Wednesday, November 25, 2009

No need to stretch

For research published earlier this year, physiologists at Nebraska Wesleyan University had distance-running members of the school’s track and field team sit on the ground, legs stretched before them, feet pressed firmly up against a box; then the runners, both men and women, bent forward, reaching as far as they could past their toes. This is the classic sit-and-reach test, a well-established measurement of hamstring flexibility. ...

Far more telling was the correlation between the various runners’ tight or loose hamstring muscles and their running economy, a measure of how much oxygen they used while striding. Economy is often cited as one of the factors that divide great runners from merely fast ones. ...

When the Nebraska Wesleyan researchers compared the runners’ sit-and-reach scores to the measurements of their economy, which had been garnered from a treadmill test, they found that, across the board, the tightest runners were the most economical. ... They also typically had the fastest 10-kilometer race times. Probably, the researchers concluded, tighter muscles allow “for greater elastic energy storage and use” during each stride. Inflexibility, in other words, seems to make running easier. ...

“It’s been drummed into people that they should stretch, stretch, stretch — that they have to be flexible,” says Dr. Duane Knudson, professor of biomechanics at Texas State University in San Marcos, who has extensively studied flexibility and muscle response. “But there’s not much scientific support for that.”

In fact, the latest science suggests that extremely loose muscles and tendons are generally unnecessary (unless you aspire to join a gymnastics squad), may be undesirable and are, for the most part, unachievable, anyway.
--Gretchen Reynolds, NYT, on how to costlessly save five minutes at the tail ends of workouts

1 comment:

Anonymous said...

However, if you are so inflexible that you can't reach down and touch your toes.... you probably need stretching. Flexibility is valuable for its own sake up to a *point*.