Is heat training more effective?

For some people, sweating during a very sizzling workout can border on a spiritual experience. For others, a cozy studio simply provides relief from the icy winter weather.

Not all heated workouts are equally sizzling: Bikram yoga classes are typically 105 degrees and 40% humidity, while other heated classes can range from a cozy 80 degrees to a scorching 125 degrees. And while sizzling yoga is probably the most eminent heated workout, sizzling pilates and sizzling high-intensity interval training classes are also popular.

Those who swear by these workouts say raising your temperature can raise flexibility, improve heart health, and even aid you sweat out supposed toxins.

Here’s what exercising in the heat really can – and can’t – do for you.

Heat can improve your flexibility.

Some compact studies suggest that applying heat directly to the muscles, such as with a heating pad, may increase flexibility and range of motion. Stretching in a heated room may have similar effects, although research in this area is constrained.

Your blood vessels dilate due to heat, allowing them to deliver more oxygen and blood to your muscles and tendons. This can aid relax muscles and raise flexibility, says Kelsey Bourbeau, an exercise physiologist at the University of Northern Iowa.

Sizzling workouts make your heart beat faster.

Even if you don’t exercise, just being in a sizzling environment like a sizzling tub or sauna speeds up your metabolism. your blood flow. Both heat and exercise make the cardiovascular system work harder, Ms. Bourbeau said. These stressors cause changes that can improve your health, such as: strengthening the heart and lowering blood pressure.

But in one thing test — funded by a nonprofit organization dedicated to promoting the health benefits of yoga — adults who practiced sizzling or frosty yoga three times a week for 12 weeks saw similar improvements in their vascular health, suggesting that exercising at both temperatures was equally beneficial.

Because you sweat more than usual when exercising in high temperatures, your workout may feel more intense as your body struggles to frosty down. Your heart rate will also likely be higher than usual, but that doesn’t necessarily mean your body used more energy during your workout, says Stacy Hunter, an exercise physiologist at Texas State University.

Some research suggests that when endurance athletes such as runners and cyclists constantly train in the heat, their bodies deteriorate start adapting to higher temperatures by sweating more and lowering your heart rate. They too produce more hemoglobinprotein that helps transport oxygen to muscles, which can be helpful improve their speed in both sizzling and temperate environments.

More sweating does not flush out toxins.

Some sizzling exercise enthusiasts claim that extra sweat can remove toxins from the body. This is a “popular but misleading belief,” Ms. Bourbeau said. Your liver, kidneys, and spleen process any toxic chemicals you’re exposed to, and while increasing blood flow during exercise could theoretically speed up this process, the amount of toxins found in sweat is negligible.

To stay protected, you should take extra precautions.

Before you show up to a sizzling class, double-check how sizzling the class will be, said Erin McNeely, a primary care physician at Corewell Health in Grand Rapids, Michigan.

The warmer, the more fluids and electrolytes you will lose. You should pay attention to how you feel in every class, but Dr. McNeely noted that temperatures above 30 degrees require special caution. (One study at Bikram yoga found that some participants’ body temperatures reached 102 to 104 degrees during classes, which may raise the risk of heat illness).

If you take a sizzling yoga class and feel more elastic than usual, be careful not to overstretch, Dr. McNeely added. Too much weight can lead to muscle strain. A little muscle tension during a stretch may be normal, but if you feel pain or discomfort, “that’s your body telling you to back out of the pose,” she said.

Make sure you show up well hydrated to any heated water class and drink throughout your workout. If you feel dizzy or nauseous, if you sweat excessively, or if your skin feels sizzling to the touch, you should take a break and go to a cooler place.

“These are all warning signs of heat illness,” Ms. Bourbeau said.

And if you’re recent to sizzling training, be patient. “Don’t go in there thinking you’ll necessarily do every pose they offer,” Dr. McNeely said, or even that you’ll perform at your usual level at first.

Give yourself time to adjust and frosty down.

Emma Yasinski is a freelance science journalist whose work has appeared in National Geographic, Undark, and elsewhere.