Hot yoga is any style of yoga performed in a heated room, typically between 80 and 105 degrees Fahrenheit. The heat is intentional: it’s designed to warm your muscles, increase sweating, and raise your heart rate beyond what the same poses would do at room temperature. While Bikram yoga is the most well-known version, hot yoga has expanded into dozens of variations practiced in studios worldwide.
How Hot Yoga Differs From Regular Yoga
The defining feature is the room temperature. In a standard yoga class, the studio sits at a comfortable room temperature, usually around 68 to 74°F. In hot yoga, the thermostat is cranked to anywhere from 80 to 105°F, often with added humidity. This changes the physical experience significantly. Your heart works harder to cool your body while you hold poses, your muscles loosen faster in the heat, and you sweat considerably more than you would in an unheated class.
The poses themselves can be identical to what you’d find in a regular yoga class. What shifts is how your body responds to performing them in heat. Your joints feel more mobile, your breathing becomes more deliberate, and the session feels more physically demanding even when the sequence is the same.
Bikram Yoga vs. Other Hot Yoga Styles
Bikram yoga is the original hot yoga format, developed in the 1970s by Bikram Choudhury. It follows a rigid structure: exactly 26 poses and two breathing exercises, performed in the same order, in a room heated to 105°F with 40 percent humidity. Every Bikram class lasts exactly 90 minutes. The studios require carpeted floors, mirrors on the front wall, and bright lighting. There’s no music, no talking among students, and instructors don’t physically adjust your posture.
Modern hot yoga studios have loosened all of those rules. A hot vinyasa class might be taught at 90°F with dim lighting and a playlist. A hot power yoga class might run 60 minutes with a completely different pose sequence each week. Some studios use infrared heating panels instead of forced-air systems, which heats the body more directly and keeps the air less stifling. The umbrella term “hot yoga” now covers everything from gentle heated flows to intense athletic sessions, as long as the room is deliberately warmed above normal.
Classes typically last 60 to 120 minutes depending on the studio and style.
What Hot Yoga Does to Your Body
The combination of heat and movement creates a cardiovascular challenge that goes beyond what the poses alone would produce. Your heart rate rises as your body works to regulate its internal temperature while simultaneously holding and transitioning between postures.
One area where hot yoga shows a measurable effect is blood pressure. A study highlighted by the American Heart Association found that participants who practiced hot yoga for 12 weeks saw their systolic blood pressure (the top number) drop from an average of 126 to 121, while diastolic pressure (the bottom number) fell from 82 to 79. Participants who didn’t take classes saw no change. Regular room-temperature yoga also has documented blood pressure benefits, so the heat may offer an additional edge.
What the heat doesn’t do, surprisingly, is burn significantly more calories. A study published in the International Journal of Exercise Science measured energy expenditure during a one-hour Bikram sequence performed at both room temperature (74°F) and in a heated room (105°F). Participants burned an average of 151 calories in the unheated session and 156 calories in the heated one. The difference was not statistically significant. Heart rate, oxygen consumption, and metabolic rate were essentially the same in both conditions. The intense sweating creates a sensation of working harder, but the calorie burn is modest for either version, roughly comparable to a brisk walk.
How to Prepare and Stay Hydrated
Hydration is the single most important factor in having a good hot yoga experience versus a miserable one. You’ll lose a substantial amount of fluid through sweat, and plain water alone may not be enough to replace what you lose. Electrolytes, particularly sodium and potassium, leave your body along with the sweat and need to be replenished.
A practical approach looks like this:
- Before class: Drink 30 to 40 ounces of water with an electrolyte supplement roughly one to two hours beforehand. Avoid chugging right before class starts, which can cause nausea in the heat.
- During class: Bring a large water bottle, ideally with electrolytes mixed in. Sip consistently when the instructor cues breaks. Some classes don’t build in formal water breaks, so take small sips between poses as needed.
- After class: Continue drinking water with electrolytes and consider a recovery snack or smoothie with protein and fruit to replenish energy stores.
Experienced practitioners often aim for close to a gallon of total fluid intake on days they practice. However, overdoing electrolyte supplements can cause stomach cramps, so four packets or scoops per day is a reasonable upper limit for most people. A simpler homemade option is water with a pinch of sea salt and a squeeze of lemon.
Eat a light meal at least two hours before class. Practicing on a full stomach in a hot room is a reliable recipe for nausea. A banana, toast with nut butter, or a small bowl of oatmeal works well.
What to Expect in Your First Class
The heat hits you the moment you walk in. Most people feel a wave of “why did I sign up for this” in the first five minutes as their body acclimates. That’s normal. The room will smell like sweat. You will sweat more than you thought possible. Bring a towel for your mat (it will get slippery) and a second towel for your face and hands.
Wear light, moisture-wicking clothing. Cotton absorbs sweat and becomes heavy quickly. Many practitioners wear shorts and a tank top or sports bra, and going barefoot is standard in all yoga styles.
If you feel dizzy, nauseated, or lightheaded at any point, lie down on your mat. This is common for beginners and isn’t a sign of failure. Your body needs time to adapt to exercising in heat. Most people find the second and third class considerably easier than the first as their heat tolerance improves.
Who Should Be Cautious
The National Institutes of Health specifically advises against hot yoga during pregnancy because of the risk of overheating, a recommendation echoed by the American College of Obstetricians and Gynecologists. Elevated core body temperature poses risks to fetal development, and the heated room makes it difficult to stay within a safe range.
People with severe high blood pressure, heart conditions, or a history of heat-related illness should be particularly careful. The heat adds cardiovascular stress that compounds the effort of the poses themselves. Older adults and anyone with balance issues, glaucoma, or significant joint injuries may need to modify poses or choose a gentler heated class rather than a full 105°F Bikram session. Dehydration risk is real for everyone, but especially for people taking medications that affect fluid balance, like diuretics.