Sweaty for nothing? Rebecca Greenfield / Polaris / eyevine

Could hot yoga really just be a waste of effort? A study suggests that the practice may offer little benefit over similarly-paced yoga at a more normal temperature.

Most forms of yoga are thought to aid relaxation and muscle strengthening. But hot yoga, which typically involves going through a strenuous 26 poses over 90 minutes in a warm and humid room, also makes people sweat intensely – which some take as a sign that it’s better for you.

To find out if this is true, 33 middle-aged adults who were previously sedentary did a three-month course of either hot yoga or similarly high-intensity yoga at a normal temperature. These people did classes three times a week, while a similar group of people did no yoga at all.


Fat-fighting?

Both yoga groups showed improvements in the health of their blood vessels compared with the control group. Their arteries became better at dilating in response to exertion – a trait that is linked to a lower susceptibility to heart disease. However, hot yoga was no better for this than doing it at room temperature.

There was one hint of a benefit from hot yoga though. Although all groups stayed about the same weight throughout the study, those who did hot yoga showed a small average reduction in the percentage of their body that is fat.

This decline in body fat was statistically significant but it was so slight – an average of only one percentage point – that it may not have had a meaningful impact on people’s health, says Stacy Hunter of Texas State University in San Marcos, who did the study. A longer course of yoga may have had more of an effect, she says.

All other health measures, such as blood pressure and cholesterol levels stayed the same across the three groups.

Journal reference: Experimental Physiology, DOI: 10.1113/EP086725/full

Read more: No sweat: Is yoga a proper workout?