Hot yoga and heated exercise rooms promise to help you burn more calories and boost your fitness. But do they really work?
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While hot yoga has been around for a while, the fitness trend of heated classes seems to be picking up. Hot workouts laud benefits like increased flexibility, more calories burned, weight loss, and detoxification. And while we know that these classes certainly make us sweat more, is the torture really worth it?

Proponents of heated classes argue that the environment serves up a slew of positives: "The heated room intensifies any practice, and I found it to be a perfect accelerator for Pilates," says Shannon Nadj, founder of Hot Pilates, LA's first heated Pilates studio. "The heat speeds up your heart rate, intensifies the workout, and makes it more challenging. It also ensures that you warm your body faster," she explains.

Aside from the physical benefits, the mental connection you develop to your body during a heated class is also different from non-heated classes, says yogi Loren Bassett, whose popular Hot Power Yoga classes at Pure Yoga in NYC are always packed. (See Is Hot Yoga Safe To Practice?) "The discipline, the pushing through when you are uncomfortable, and finding comfort in discomfort-if you can overcome that, then you can translate that to your life off the mat. When the body gets stronger, the mind goes along for the ride."

Heated classes are not for everyone though. "Individuals who do not respond well to working out in hot conditions or individuals with underlying heart issues should be careful. It's important to acclimate slowly and to always stay hydrated. Understand your own limitations," says Marni Sumbal M.S., R.D, an exercise physiologist who has worked with athletes when they are heat training. (Avoid dehydration with The Art of Hydration During a Hot Fitness Class.)

Heat training, while still emerging in boutique fitness, has long been used by athletes when preparing for hotter race environments than they are used to. Because they're already acclimated to hotter temps on race day, they start to sweat sooner to cool down and will lose less sodium in their sweat, reducing the risk of dehydration. You won't necessarily burn more calories or speed up weight loss just by working out in the heat though, says Sumbal. When the body gets hot, the heart does pump more blood to help cool the body, but the slight increase in heart rate doesn't have the same effect as running short intervals on the treadmill, explains Sumbal.

In fact, a 2013 study from the American Council on Exercise monitored the heart rate, rate of perceived exertion, and core temperature of a group of people doing a yoga class at 70 degrees, then the same class a day later at 92 degrees, and found that heart rate and core temperature of all participants were about the same during both classes. Researchers also noted that at temperatures of 95 degrees or more, results could differ. Overall, they found that hot yoga was just as safe as regular yoga-and while participants heart rates were similar during both classes, most participants rated the hot class as more difficult.

The bottom line: If hot classes are part of your routine, you can safely keep doing them. Just not digging it, don't sweat it.