I use hangovers as an opportunity to complain, eat, sleep and cancel plans more than usual. I’ve never understood those friends of mine who like to “sweat it out.” Why sweat when you could order morning pizza? But, after a set of winter weeks spent re-immersing myself in the world of hot yoga, I began to think about sweating differently. Maybe my friends were on to something.
As a former high-school Bikram devotee looking to cross-train, stretch and grow an ab or two, NYC’s Y7 Studio is right up my alley. It’s an hour of sweaty, 90-degree vinyasa set to hip hop, indie and other unidentified “good songs” that I’d Shazaam the shit out of if I had my phone on me. Thanks to Y7, my balance has improved, I’m stronger — which has made my other workouts more productive — my whole body has tightened, I’m more conscientious of what I eat and drink, I sleep better and I’m less ready to spontaneously combust like an angry human pimple in anxiety-thick situations. There is no going back; this is my thing now.
But! I wanted to know if there was actual science behind the purported benefits of hot yoga’s heat, or if all that sweating simply felt good. Could I get the same advantages without the dramatics?
Sarah Levey, co-founder of Y7 Studio, is (obviously) a proponent of heated exercise. First, she explained why the infrared heating technology their studios use is different than, say, turning up the thermostat in your prewar shoe box, shutting all the windows and getting into a downward-dog position.
Rather than blowing hot air on your skin, she told me infrared heat warms up molecules in air, which warms your blood and organs, then the skin. “It’s a dry heat,” she explained. “Arizona versus Miami.”
We talked heat-for-health benefits. “Heat is good for circulation,” said Levey. “Good blood circulation rids the body of old cells, which helps cell rejuvenation. You need those new cells for wound recovery. Blood moves quicker, so you’re able to push out toxins. Infrared heat, specifically, eases inflammation and calm the nerves. Finally, because your blood flow speeds up and circulation increases, your body begins ridding itself of fat cells and weight loss is promoted. Just by being in the room for an hour, you’re burning 200 to 300 calories.”
I can’t repeat this enough: The way I feel after a Y7 Studio class is…high? High and amazing and healthy, as though I want to live off of green things for the rest of my life and never get mad at anyone ever again. I’ve gone hungover and left feeling brand new. But does it actually detox you? Is that possible?
“Certain poses, like a twisted chair, put pressure on and bring blood to specific areas of your body that can have a detox effect,” Levey said. “But it’s probably not going to reverse the six drinks you had last night. Sweat is an outlet. You sweat when your heart starts pumping. You get your heart rate up in class, your blood moves faster, you begin flushing out old blood cells and recirculating new ones. You feel better because you’re not stagnant, your blood is not stagnant, you’re moving.”
“Not all sweat is created equal,’ Berlingeri told me. “Traditional workout sweat is salty, it smells funny. That’s because cortisol, the stress hormone, is activated. Infrared saunas lower your cortisol levels and up serotonin, so your body is in a state of healing.”
Her belief is that infrared heat pulls heavy metals, radiation and environmental pollutants out of fat cells. “The only time you can truly detox is when your body is in state of healing,” she told me. “Think about night sweats.” (Always do!) “That’s your body trying to heal. It can’t detox while working out because it’s in flight-or-fight mode. You know how you feel smelly and sticky after working out? After an infrared sauna session, you will feel clean and light. It’s a purge unlike any other.”
All of this sounded great. I’m a sucker for all sorts of alternative-medicine hypebeasts and am sold no matter what (very G.P. of me). BUT, I figured it was time to talk to an MD. I called Dr. Jordan Metzl, “The Athlete’s Doctor,” named one of New York’s top sports medicine physicians by New York Magazine. His professional opinion about whether people actually sweat out substantial toxins (including metals) was that they do not; if they could, he said, he hadn’t heard of supporting research. “Your kidneys are more involved with filtering out toxins than sweating.”
“In general, sweating needs to be looked at mechanically,” he told me. “The primary way the body cools itself is evaporation. When your body sweats, and that sweat evaporates, the evaporation reduces your core body temperature. Your skin is usually responsibly for maintaining your core body temperature so you don’t overheat, like a car. If you overheat, that can lead to heatstroke or other heat-related illnesses, which can range from annoying to deadly. Your sweat mechanics are hugely important.”
Now, everyone has a different sweat rate, he told me. Certain people sweat more than others for a whole variety of reasons: weight, resting body temperature, fitness level. Interestingly, the more fit you are, the faster you sweat because your body is conditioned to cool itself more quickly. Also, sweat isn’t the sole indicator that you’re getting a workout. You can tone your muscles or raise your heart rate without beading or dripping. Think about Pilates, barre or non-heated vinyasa yoga.
The environment contributes to your sweatuation. When it’s hot, we sweat. (Duh.) But when it’s humid, our sweat can’t evaporate off the skin, which accounts for that so-hot-I-can’t-breathe feeling. A hot, humid setting has the highest risk of heat illness — so take care to hydrate during non-infrared hot yoga or other humid-climate workouts. I’d like to point out that this is a great excuse to whip out anytime anyone asks you to do literally anything during an East Coast summer.
As for the supposed metabolic benefits of infrared saunas and, more specific to our conversation, infrared-heated yoga, Dr. Metzl didn’t agree with the claims I listed, but he also didn’t have a problem with them. “So long as you hydrate before and after and replenish the water you’re losing, so long as you don’t overstretch a muscle because you’re warmer than usual, hot yoga is fine.”
Good news, because I’ve got sweaty sleep scheduled for around 4 tomorrow morning (non-infrared), and a Y7 class at 9 a.m.
Illustrations by Maria Jia Ling Pitt.