For some people, sweating during intense exercise may border on the spiritual experience. For others, studying in high temperatures simply provides relief from the harsh winter weather.
Not all high-temperature workouts are created equal: Bikram yoga classes are typically 40 degrees Celsius with 40 percent humidity, while other high temperatures can range from a scorching 26 degrees Celsius to a scorching 51 degrees Celsius. Although hot yoga is perhaps the most popular hot workout, hot Pilates and hot high-intensity interval training classes are also very popular.
Those who believe in these workouts claim that turning up the heat can increase your flexibility, improve your heart health, or even help you get rid of supposed toxins.
Here’s what exercising in high temperatures can — or can’t — do for you.
Heat can improve your flexibility
Some small studies suggest that applying heat directly to muscles, such as from a heating pad, can increase flexibility and range of motion. Stretching in a hot room may have similar effects, although research on this is limited.
Blood vessels expand with heat, allowing them to deliver more oxygen and blood to muscles and tendons. This can help relax your muscles and make you more flexible, said Kelsey Burpo, an exercise physiologist at the University of Northern Iowa.
Heat can make your heart work
But in one study — funded by a nonprofit dedicated to promoting the health benefits of yoga — adults who practiced hot yoga or cold yoga three times a week for 12 weeks saw similar improvements in vascular health, suggesting that exercising at any temperature It was helpful. Equally useful.
Since you’ll also sweat more than usual while exercising in high temperatures, your workout may feel more intense as your body struggles to cool down. It’s also possible that your heart rate is higher than normal, but that doesn’t necessarily mean your body is expending more energy during training, said Stacy Hunter, an exercise physiologist at Texas State University.
Some research suggests that when endurance athletes, such as runners and cyclists, consistently train in the heat, their bodies begin to adapt to higher temperatures by sweating more and lowering their heart rates. They also produce more hemoglobin, the protein that helps transport oxygen to your muscles, which can help improve your speed in hot and temperate environments.
Sweating more does not remove toxins
Some hot exercise enthusiasts claim that excess sweat can transport toxins out of the body. This is a “common but misleading belief,” Bourbeau said. Your liver, kidneys, and spleen process any toxic chemicals you’re exposed to, and although increased blood flow during exercise can theoretically help speed up the process, the amount of toxins found in sweat is negligible.
You should take extra precautions
Before you attend a hot exercise class, check exactly how hot it is, said Erin McNeely, MD, a primary care physician at Corwell Health in Grand Rapids, Michigan.
The hotter it is, the more fluids and electrolytes you lose. You should pay attention to how you feel in any classroom, but McNeely noted that temperatures above 37 degrees Celsius require extra caution. (A study of Bikram yoga found that some participants’ core temperatures reached 38 to 40 degrees Celsius during class, which may increase the risk of heat illness.)
If you’re taking a hot yoga class and feeling more flexible than usual, be careful not to over-stretch, McNeely adds. Overexerting yourself can cause muscle strain. “Slight muscle tension during a stretch may be normal, but if you feel pain or discomfort, your body is telling you to move away from the pose,” she said.
Make sure you are well hydrated in any high-heat exercise class and continue to drink throughout your workout. If you feel dizzy or nauseous, if you are sweating excessively, or if your skin feels hot to the touch, you should take a break and move to a cooler area.
“These are all signs of heat illness,” Bourbeau said.
And if you’re new to high-temperature training, be patient with yourself. “Don’t think that you’re necessarily going to do all the poses that they show,” or even that you’re going to perform at your usual level at first, McNeely said.
Give yourself time to adjust and enjoy the sweat.
Emma Yasinski is a freelance science journalist whose work has appeared in National Geographic, Undark, and other media outlets.
