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Why Do I Sweat So Much? A Shirt-Drenched Look at Thermoregulation

Why Do I Sweat So Much? A Shirt-Drenched Look at Thermoregulation

I was walking through the parking lot on a hot and humid early September day. Step by step I got closer to the front entrance of my favorite grocery store. I had just finished up my morning cardio, which for 300 pound guys like myself, started with just trying to tie my shoes in one breath.

Despite the humidity, I hadn't really been sweating. My bike ride around the trails of the local public park was challenging, but my shirt was still dry. Moving the 29" mountain bike tires taxed the legs, especially while dealing with the soreness from yesterday's squats.

My lungs were working overtime as my lower extremities struggled to haul my gigantic back end up one hill after another. I must have looked cartoonishly slow. It probably didn't help that in addition to my massive downforce, the brakes were out of alignment and rubbed a little against the tire.

Back to the store...

A cold blast of chilled air hit me square in the face when I hit the entrance, welcoming me to a nice 68 degree shopping experience. Despite the cold chill of the produce meat and beer sections, I was now beginning to sweat so profusely that I looked like I just ran the Boston marathon, climbed Everest, and went 12 rounds with Mayweather in a packed Turkish steam room.
Josh Mac

Article author Josh Mac sweating like a fat man boxing Floyd Mayweather in a Turkish steam room.
That got me wondering:

Why had I barely sweated during the time I was going ape mode on my bike in the balmy, butt crack-like heat of early September in the Carolinas, and now in the comfort of AC and the open refrigeration of the beer aisle, I looked like I'm actually melting?

Now I know what you're thinking, and yes, I'm a pot-bellied powerlifter who was shopping for beer right after doing cardio, of course I was sweating. But I remember this happening as far back as grade school when I was actually in shape.

In my pre fat-lard years, before the Duluth trading company underwear and Extra Strength Breathe Right Strips, I can recall in vivid detail the inability to stop sweating after I stopped exercise no matter how cool I tried to make myself. The waterworks would start from the minute after changing out of gym clothes halfway into my next class. Even back then it was a real pain in my sweaty arse.

As I explained to the visibly disgusted checkout cashier that I had just been at the park exercising and that I wasn't robbing the place or having a heart attack, I thought: there must be an actual reason for this madness.

The answers lie somewhere in science, and the reasons may surprise you.

Diet and Profuse Sweating?

Turns out that the things I mash into my face might actually be having an impact on my health. Go figure. Foods said to exacerbate sweating include garlic, onions, and spicy foods. But two other things in particular stood out, two of my favorite things actually. Yep, caffeine and alcohol.

CoffeeCaffeine, as a stimulant, is a light kick in the central nervous system's groin. As a diuretic it dehydrates the body. Those morning coffee(s) raise the resting pulse, increase circulation and have a lowering effect on the ol' insulin level. All of which can trigger the sweats.

Alcohol, on the other hand, has the opposite effect on the CNS. Alcohol (in my case, beer) also dehydrates the crap out of you, and in addition can raise body temperature. Alcohol consumption also increases the sensation of being hot even as the body cools down from excess sweating.

Next day symptoms associated with a hangover include sympathetic hyperactivity like tremors, increased blood pressure and sweating. Butt crack sweat city, population: me.

It's hard to narrow down which of these is contributing to my sweaty condition since I partake in all of them on a regular basis. Each day is either filled with beasting weights or drinking spicy garlic and onion beer-battered coffee shakes. Some days both. But the few beers that I had the night before had long since been metabolized and left my system, and I didn't drink nearly enough of them to warrant a hangover.

And a study by the Faculty of Health Sciences, McMaster University, Hamilton, Ont., Canada concluded that moderate amounts of caffeine showed no significant increase in perspiration rate during exercise over levels of a placebo in their male test subjects. Maybe it isn't the coffee, but what else could it be then?

Thermoregulation and Sweat

Caffeine and alcohol aren't the only things that affect thermoregulation in the body. According to Dr. Gabriel Mirkin MD, (LOL, I'm picturing a Merkin now) excess heat from muscle tissue during exercise is also a culprit. In his May 11, 2013 article, Dr. Mirkin states:

"When you exercise, more than 70 percent of the energy that powers your muscles is lost as heat. Less than 30 percent drives your muscles. Athletic competition can drive temperatures as high as 105 degrees without harming the athletes."

He goes on to explain that as the heart rate increases during exercise, heat from the muscle tissue is carried by the blood to the skin for cooling through the evaporation of sweat. Once exercise stops and the heart rate returns to normal, the warmed blood is then pumped more slowly from the hot muscle tissue to the skin for cooling, causing a temporary rise in body temperature and MORE SWEATING.

There could be several factors for my turning into a liquid disaster after I lift or do cardio.

Another reason could be that I'm just a naturally sweaty bastard. Luckily, people that went to way more college than you or I named this condition something a little more scientific sounding, hyperhidrosis.
Josh Mac
Fear not, Josh Mac isn't going to pop. He's simply a sweaty bastard.

Hyperhidrosis, or Excessive Sweating

Although hyperhidrosis usually refers to people who sweat abnormally outside of exercise or higher temperature, those suffering with this condition can sweat more than the average Joe during those activities. Causes range from social anxiety, excessive body mass, thyroid problems and diabetes. Oh, snap.

Another form of hyperhidrosis is Primary Focal Hyperhidrosis, which affects only specific parts of the body, i.e. sweaty feel, hands or pits when other parts of the body are not perspiring. Clinical antiperspirants and sweat shields might help, but I can probably rule this one out since I was glistening head to toe equally like a 6 foot tall freshly glazed donut.

Crazy palm sweating and awkward handshakes aside, excessive sweating may also be due in part to body mass. As stated, I'm pushing 300. It takes a good amount of energy to get moving and stay in motion. Not that the BMI chart in my doctor's office takes in to account how jacked I am, but I'm pushing severely obese by its standards.

I burn more calories than I would if I were doing the same activity at a weight of say, 200 pounds, and that level of activity creates a lot of heat. Could there be another reason besides excessive heat stored in the body that I look like I just climbed out of a stagnant storm runoff pond?
Jacked Chart
Which one's the Jacked column?
Some clever Canadians might just have the answer:

"In a 2003 study conducted by the Human Performance and Environmental Physiology Research Laboratory, School of Human Kinetics at the University of Ottawa, 8 athletes were either subjected to varying amount of physical exertion by way of a treadmill, or put in a control group (no exercise.) The subjects body temperature, oxygen consumption (Vo2) and sweat rate were measured and compared between the control group and the exercise group (subjects who rested in an upright, seated position after a set amount of time on the treadmill and those who continued at a lower rate of intensity.)

Hold on, I have chest pains. Ok, I'm fine.

I bet you can guess the results. The exercise group obviously had a higher sweat rate and it corresponded directly with the degree of intensity. DUH! But other data was also collected.

As you'd expect, heart rate, skin temperature, and core temperature were all elevated in the exercise group versus the control group, but the researchers also noted a reduction in blood pressure (post exercise hypotension) in the group who exercised. The lower blood pressure causes blood pooling in the lower extremities and thus lower central blood volume for up to a couple of hours post exercising. The changes in blood pressure are thought to modulate sweat gland activity by triggering the baroreceptor (sensory neuron that is excited by stretch of the blood vessel) reflex.

Well slap me silly.

Now, what can I do to keep from looking like a wax figure next time I leave the gym? The internet is full of answers. Doctors and internet experts on Reddit alike all recommend cold showers and resting for 15-20 minutes to allow the heart rate and body temperature to return to normal. But if post-exercise hypotension is really the culprit, wouldn't something like a gradual cool down period of less and less intense intensity help?

I gradually work up to the intensity during cardio and lifting, so should I also not work back down? Should that walk into the store have been done back at the park before I got into my frigid air-conditioned vehicle and sat still as I drove? The sudden decrease of activity from balls-out cardio to seated position was pretty abrupt to say the least.

Cool Down Sets

Cool down sets are usually touted by some for their perceived ability to help reduce muscle soreness and aid in recovery. Although research has shown that performing cool down sets doesn't necessarily aid in those aspects, do they actually serve a purpose?

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."

A quick look up of the symptoms associated with hypotension revealed... get ready for it... SWEATING.

Drops mic.

Now I'm not sure which of these factors could be the reason that I sweat worse than Subway's advertising executives each time I up and leave the gym. But despite the studies I've cited, perhaps limiting caffeine, eating a little better and ugh... "drinking less" combined with using some cool down sets might just make a dent in the awkward dripping noise heard while I'm waiting my turn at the deli counter. Heck let's be honest, it really couldn't make me sweat any more than I already do.
References
1) Can J Physiol Pharmacol. 1990 Jul;68(7):889-92. Effects of caffeine ingestion on body fluid balance and thermoregulation during exercise.
2) Falk B1, Burstein R, Rosenblum J, Shapiro Y, Zylber-Katz E, Bashan N. Effect of exercise intensity on the postexercise sweating threshold.
3) Glen P. Kenny, Julien Périard, W. Shane Journeay,Ronald J. Sigal, Francis D. Rexecutives Journal of Applied Physiology Published 1 December 2003 Vol. 95 no. 6, 2355-2360 DOI:10.1152/japplphysiol.00651.2003
4) "Dr. Gabe Mirkin on Health, Fitness and Nutrition. » Why You Sweat More After Exercise." Dr. Gabe Mirkin on Health, Fitness and Nutrition. N.p., n.d. Web. 14 Sept. 2015.
5) http://well.blogs.nytimes.com/2013/04/24/do-we-have-to-cool-down-after-exercise/
6) Effects of alcohol on thermoregulation during mild heat exposure in humans. Yoda T1, Crawshaw LI, Nakamura M, Saito K, Konishi A, Nagashima K, Uchida S, Kanosue K.
7) Alcohol Hangover Mechanisms and Mediators Robert Swift M.D., Ph.D.; and Dena Davidson Ph.D.
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