The Truth About Hot Yoga (Explained by Science)

Kaisa Kapanen
The Truth About Hot Yoga (Explained by Science)

Practicing yoga in a hot room can be very comfortable, especially if you live in a colder climate. If you have tried it, you know the excess sweat and the feeling that your body is going through something extra compared to a yoga at room temperature. But is hot yoga really as beneficial as it said to be? Let’s find out.

Hot Yoga and Cardiovascular Health

One of the main selling points of hot yoga is that it’s said to burn more calories than yoga at room temperature. Is there any merit to this claim?

In a study published in the journal Experimental Physiology, researchers compared sedentary but healthy adults aged 40–60 who were divided into three groups. Two groups practiced for 90 minutes three times a week, for 12 weeks: The first group practiced in a hot room (40.5°C) and the second group practiced at room temperature (23°C). The third group did not practice yoga at all.

The study concentrated on the vascular health of the participants and concluded that both groups practicing yoga gained similar health benefits, regardless of the temperature of the room.

Another study, funded by the American Council of Exercise, recruited 20 healthy volunteers between the ages of 19 and 44. The volunteers participated in a regular yoga class at room temperature, and an identical class held at a hot temperature. During both yoga classes, the participants’ heart rates and core body temperatures were measured.

The research showed no significant difference in heart rate or core body temperature between the regular yoga class and the hot yoga class (although participants were sweating a lot more in the hot yoga, for obvious reasons).

Although we sweat a puddle, it seems like for cardiovascular health there are no additional benefits from hot yoga.

Does Hot Yoga Make Us More Flexible?

Let’s face it, hot yoga (whether Bikram yoga or other styles) can be a relaxing and satisfying experience. When done correctly (staying hydrated and not pushing oneself to the limits), it is healthy for us.

In an article published in the New York Times, several medical professionals were interviewed regarding hot yoga and flexibility. When we think about flexibility, we need to remember that this comprises two types: muscular flexibility, and flexibility of the joints and ligaments. Heat increases the metabolic rate, and when we are warm, we can stretch the muscles more. However, if we stretch the muscle by more than 20–25 percent of its resting length, we can start to damage the muscle.

When it comes to joints and ligaments, less is more. Although ligaments do have some flexibility, they don’t get much blood flow. Ligaments are there to stabilize the joints, and if the ligaments stretch out they do not have the capability to bounce back like muscle does, leading to joint instability. For hot yoga lovers, this means that there is a risk of accidentally going beyond the body’s natural limits, which can cause injuries.

What About Sweating Out Those Toxins?

You know the feeling, sweat is dripping and by the end of the class, you are swimming in a puddle. This has to be healthy, right? 

Most of what we are sweating is water, with trace amounts of urea, lactic acid and minerals. The body does not sweat out metabolic byproducts in high enough quantities to be beneficial for the body’s metabolic function. True toxin elimination is performed by the kidneys, liver, and colon. Hot yoga is therefore not really releasing toxins as much as dehydrating us and making us lose water weight. So drink up, hot yogis! 

But Hot Yoga Feels So Good!

Of course it does! As someone who grew up close to the polar circle, I understand the allure of a warm room during cold winter days.  If you love hot yoga, great, keep going and keep doing what you love. It will relax you and give you great health benefits (as yoga does). 

Just remember to keep hydrated, listen to your body, don’t push yourself and take a break (or walk out) if you feel lightheaded or unwell. And remember, there are many forms of yoga done in a heated room, not only Bikram. Try Hot Yin Yoga for an ultimate relaxing experience. 

Enjoy!

Image credit: Sanàa Jaman