Is the Exercise Cool-Down Really Necessary?
 

Did a search, did not see this NY Times article posted and discussed:

Is the Exercise Cool-Down Really Necessary?

Not sure if I agree with its premise, that cool-downs are unnecessary. We've all heard of the guy dropping dead after stopping a run, a ride, etc, with no warm down. I know not all the conventional wisdom has been correct over the years (especially stretching before workouts), but why do people seem to drop dead after workouts instead of during?

Last weekend, I climbed a short hill hard, and hit 180BPM on the HRM. I stopped at the top of the hill to turn around, as space was tight. I immediately was hit with a wave of nausea. As soon as I started pedaling again, it went away. From now on, no more quick stops without a cool-down.

Thoughts? Links? Peer-reviewed studies?

Selection effect: if you drop dead, your workout is necessarily over. To a less extreme extent, perhaps the person stopped because they already weren't feeling well. I wouldn't put much to such anecdotes one way or the other.

Google "exercise hypotension". This is different than postural hypotension.

You want to get a good feel for it, go do a set of 30 heavy squats. You'll have to hold onto the bar when you're done. I can't remember the exact mechanism, but heavy exercise causes changes to the chemistry that regulates blood pressure. When you suddenly stop exercising, it takes a few seconds (that's seconds) for things to get re-regulated. During that time, you feel pretty crappy and may nearly pass out.

But you've watched TdF on TV, right? When those sprinters hit the line, they just stop after a hundred feet or less, right? No cool down, or no more than a few seconds of cool down. I never cool down, because the last bit to the car or house will always be taken a bit more slowly, and it only takes a few seconds for things to adjust.

People who experience the worst post exercise hypotension usually do so as a result of heart disease. I've never known anyone to drop dead at the end of a ride, though I have known of club riders who did so in the middle of a climb. In fact, I've never "heard of the guy."

Ever noticed how pumped your legs are after a good, hard effort? That's a lot of blood, and some extracellular fluid (was blood plasma...). During exercise, the force of the muscle contractions help push the blood back to the heart, and the venous pressure is necessarily low. If you suddenly stop this pump, and the vasculature is still dilated from exercise, you get hypotension. This is because the Frank-Starling mechanism works on pre-load; basically it's a reflex that causes your heart to pump the more it is stretched (filled). If it is suddenly underfilled, because venous return is compromised, stroke volume suddenly falls.

When you're young and your blood vessels adapt much more quickly, it usually doesn't go so far as to make you pass out or anything. As you get older, the odds of something negative happening is greater. Aren't they always?

Just turned 25, and I can definitely see the value of a good warm-up and my foam roller a lot more than I could even 5 yrs ago. I figure it's only a matter of time before I personally value an active warm-down, as opposed to objectively seeing its merits.

I believe its triggered by increased NO production which dialates the blood vessels, such that no matter how hard the heart is pumping, the blood pressure drops. Of course, that's assuming no cardio issues such as diseased valves or blocked arteries.

Interesting thread. Today after running I noticed I felt worse walking to my car than I did running my last lap and the look on my face was not pleasant.

Reading some of these replies - sounds like the intuitive impulse to lay down might be good for you.

An active recovery is usually advised to help clear the muscles, which are engorged with blood, and return that blood to the systemic circulation more quickly. Lying down, to prevent injury, might be the thing to do if you feel like you're going to fall down from passing out. In this case, you probably overdid it a bit.

Many competitive athletes also swear by active recovery for better training results and quicker recovery.

I suffer from asthma. The answer is yes.

I have experienced some of those crappy feelings after an intense workout before especially if I still feel somewhat energetic and was told by my doctor my enlarged heart and irregular heartbeat may have had something to do with it. I'm not entirely sold on that but I try to cool down if I can.

Adding to that, when you are working out, blood is shunted away from the body parts that do less work for the body parts that are doing more work. Working muscles need more oxygen- they need more blood flow. But when you suddenly stop, you risk the pooling of blood in the working extremeties, and those other areas of the body (such as the brain) will be lacking oxygen. That is why sometimes people feel lightheaded after they finish their workout. In that case, I usually have to get them back into moving around. Of course, if they're already passing out (which I've had to deal with before), then that's the time to get them on the ground and elevate their legs so they can get the blood flow back up to the brain and upper extremities.

koffee