Do you often skip cooling down after exercise? A small but soothing body of new research suggests that you aren't missing out on much.
We were all taught by our grade one phys-ed teacher that the body needs a cool down period after exercise. Our coaches in high school told us that by slowing down to a jog or otherwise decreasing the intensity of our workout, followed by some stretching exercises, we could prevent muscle soreness, improve flexibility and speed recovery. This would all allow us to perform better physically the next day.
It appears however that none of these ideas stand up to new scientific studies very well.
In a study published last year in The Journal of Human Kinetics, a group of 36 adults undertook a one-time program of forward lunges while holding barbells, an exercise almost guaranteed to make people extremely sore the next day. Some of the participants warmed up beforehand by pedaling a stationary bicycle at a very gentle pace for 20 minutes. Others didn't warm up but cooled down after the exercise with the same 20 minutes of easy cycling. The rest just lunged, neither warming up nor cooling down.
24 hours later, all of the volunteers submitted to a pain threshold test, in which their muscles were prodded until they reported discomfort. The volunteers who'd warmed up before exercising had the highest pain threshold, meaning their muscles were relatively pain-free.
Those who'd cooled down, on the other hand, had a much lower pain threshold; their muscles hurt. The cool-down group's pain threshold was, in fact, the same as among the control group. Cooling down had bought the exercisers nothing in terms of pain relief.
Given these findings, then, is there any valid reason to cool down?
Yes, says Andrea Fradkin, an associate professor of exercise science at Bloomsburg University in Pennsylvania. "A cool-down has been shown to prevent venous pooling after exercise, or the buildup of blood in the veins," she says. During prolonged, vigorous exercise, the blood vessels in your legs expand, meaning that more blood moves through them. Stop exercising abruptly, and that blood pools in your lower body, which can lead to dizziness or even fainting.
This can be combatted easily however by walking for a few minutes after your workout. This will allow for normal circulation to the brain.
If a formal cool-down provides few confirmed physiological benefits, it may have a worthwhile psychological effect. "If you've done a very hard track session, it's nice to end with some light jogging," Dr. Tucker says, just to restore a subjective "sense of normality to your legs.
A cool-down, in other words, feels nice. Both mentally and physically.