Sweat, while a completely natural (and essential!) bodily function, can prompt all sorts of questions (including “why the heck am I sweating so much?!”). Here are the answers to some commonly asked questions about sweat.
The fitter I get, the more I sweat. Why is that?
“There are two main reasons. One is that as you improve your fitness, you tend to exercise more intensely, which can make you sweat more,” explains Mary Beth Brown, Ph.D., an associate professor in the Department of Physical Therapy at Indiana University. “The other is that you get better at sweating the more you do it.” You’ll start perspiring earlier in your workout, and more of your sweat glands will be activated to help rid your body of excess heat.
But keep in mind sweat isn’t the only measure of how hard you’re working. A better indicator of your performance is how difficult it is to talk midway through an activity. During a moderate-intensity workout, you should be able to speak in broken sentences; during vigorous exercise, you should be able to manage only a few words at a time.
Why does sweat burn my eyes?
“Sweat contains salt, which can irritate the eyes. Plus, it’s slightly acidic compared with the eye’s fluid,” Brown explains. While sweat won’t actually harm your eyes, if perspiration is interfering with your workout, wear a sweatband to trap moisture before it has a chance to drip.
Is hot yoga any healthier than regular yoga?
Cranking up the thermostat in the studio has only modest perks. “Some people find that the heat improves their flexibility and range of motion, making it easier to get into poses,” says Cedric X. Bryant, Ph.D., the chief science officer for the American Council on Exercise, who has studied hot yoga. If you’re hoping to sweat off a few pounds, though, forget it; the difference in calorie burn between the two types of yoga is almost negligible.
That said, the room’s humidity can pose some risks, as sweat doesn’t evaporate, making it harder for your body to cool itself. To stay safe, drink cold water every 15 minutes, and if you’re doing hot yoga for more than an hour straight, swap water for an electrolyte-spiked sports drink to make up for the sodium and potassium you’re sweating out. Be especially careful during Bikram yoga, which is hotter and more humid than regular hot classes. Try starting with shorter, cooler classes and working your way up to a full-length Bikram session.
Why do I sweat for so long after my workout?
“When you stop exercising, your body continues to generate heat to fuel functions like restocking your energy stores and redistributing your blood flow,” Brown explains. As a result, your core temperature can stay elevated, triggering perspiration even post-shower.
To cool down and dry off quicker, refrain from taking a super-cold shower or splashing icy water on your face. “The chilly temp constricts your blood vessels, causing hot blood from your skin to rush to your core, raising your body temperature,” says hydration expert Stacy Sims, Ph.D., an exercise physiologist and senior research fellow at the University of Waikato in New Zealand. Instead, when you’re done exercising, take a coolish (not freezing) shower, then stand in front of a fan to evaporate any lingering sweat before it beads up. You can also try sipping ice-cold water before and during your workout, Sims says. Her research found that this minimizes the rise in your core temperature, which may help you stop sweating sooner.
Can you really sweat out toxins?
“Yes and no,” says Juan Del Coso, Ph.D., a professor of human physiology and exercise at Universidad Camila José Cela in Spain, who has studied the issue. “When you sweat more, you do lose some toxins, but not enough to have a measurable health benefit.” If your body needs to get rid of something noxious, your kidneys flush it into your urine, not your sweat. So don’t hit the sauna; you’re better off drinking plenty of water and eating veggies with a high H20 content to recover after a rough night.
Why do I sweat when I’m nervous?
Blame your prehistoric ancestors. Unlike the sweat you produce at the gym, which is mostly water, the type you pump out during anxiety-provoking situations is laced with pheromones that stimulate your amygdala, the area of the brain that controls your fight-or-flight response, according to research from Stony Brook University.
The last thing you want is for your pheromone-packed sweat to broadcast “She’s freaking out!” when you’re trying to play it cool during a job interview or a blind date. So don’t stop at your underarms when it comes to applying antiperspirant—also hit around your groin, where apocrine glands produce nervous sweat, says Lilianne R. Mujica-Parodi, Ph.D., the author of the Stony Brook study.
Also, try working up a sweat at the gym before the stressful event, Mujica-Parodi suggests. When you’re anxious, your levels of the stress hormone cortisol rise in order to give you energy to fight or run away. “But today most stressors don’t involve fighting or fleeing, and the extra cortisol only makes you more nervous and reduces your ability to think analytically,” she says. Exercising gets rid of the excess so you can stay focused—and dry—when it counts.