Adam’s training journal
Not long ago, my sister and I went for a run. In the last mile or so, we picked up the pace. When we hit the end of my driveway, I pulled up immediately and began walking to the door.
“Do you want to cool down?” Alison asked.
I shrugged. The thought hadn’t even crossed my mind. Every morning, no matter whether my workout ends in a jog or sprint, I pretty much come to a full stop at my doorstep. Even on the treadmill, where the machine tries to enforce a five-minute cooldown at the end of my runs, I hop off rather than jogging and, finally, walking to conclude my workout.
As Ali and I jogged a few laps around my cul-de-sac, I began to wonder: Have I been shortchanging myself by skipping cooldowns?
Dr. Prescott prescribes
As far as I can tell, the cooldown is as old as exercise itself. I can’t be sure, but no doubt a few trainers through the years have attributed the death of Pheidippides — who purportedly ran from Marathon to Athens to proclaim the Greek victory at the Battle of Marathon, then promptly keeled over — to his failure to cool down.
When you exercise hard, the blood vessels in your legs expand to send more blood to your legs and feet. Your heart pumps quickly. So, if you come to a sudden stop, your heart slows down, and your blood pools in your legs. This can lead to feelings of dizziness or even loss of consciousness.
This phenomenon could be dangerous for someone with heart disease, where vessels leading to the heart are already narrowed. But there doesn’t seem to be a lot of data on the topic.
For a healthy person doing a typical workout, there’s not a pressing physiological need for a cooldown. For a time, physiologists and trainers justified the practice as a way to dissipate lactic acid that built up during exercise. But it has since been shown that lactic acid is fuel, not a deleterious byproduct of exercise, and it has nothing to do with soreness.
In fact, one study of cyclists concluded that it is better not to cool down after intense exercise. When the cyclists cooled down, their bodies wasted the lactic acid, burning it up to fuel the exercise. But if the riders simply stopped, their body transformed the acid to glycogen, which was stored in their muscles to fuel future efforts.
Another study looked at subjects who walked backward on a treadmill for 30 minutes, an exercise that can lead to sore muscles. It found no difference in post-workout soreness between those who were randomly assigned to do a 10-minute cooldown walk and those who were simply told to stop.
If you do a hard workout, you might want to do a brief cooldown to avoid any possibility of dizziness. But other than that, you should be cool with no cooldown.
[ask-drp]
