Bikram yoga claims to boast energy expenditure to 1000 calories per session. However, these claims are increasingly being challenged. Studies are saying that Bikram yoga is similar to other yoga styles in burning about 300 calories per hour.

Last year an American university found that hot yoga does not make the body work harder than any other type of yoga. Dr Cedric Bryant, chief science officer of the American Council on Exercise (ACE) said: ‘The benefits are largely perceptual. People think the degree of sweat is the quality of the workout, but that’s not reality. It doesn’t correlate to more calories.’

A recent study set to determine the exact energy expenditure, heart rate, and sweat rate in novice and experienced practitioners from a standardized Bikram yoga class. Data were collected in the environmental chamber of the Exercise Physiology Laboratory at San Diego State University in California, USA. Five male and nineteen female participants between the ages of 18 and 57 years were recruited and classified as experienced or novice practitioners, having completed ≥20 or <20 sessions.

Participants were guided through a standardized 90-min yoga class performed in a hot environment using Bikram’s Standard Beginning Dialogue, while expired gas was collected and heart rate was recorded. Energy expenditure, calculated via oxygen uptake, and heart rate were determined for each posture and transition period. In addition, sweat rate and core temperature were recorded for each participant.

It was found that the mean absolute energy expenditure was about 300 calories. Novices expended approximately 3.7 calories/kg while experienced practitioners were higher at 4.7 calories/kg. Percentage of predicted maximum heart rate and sweat rate were 72% and 0.6 kg/hr in novice practitioners and 86% and 1.1 kg/hr in experienced participants.

These results mean that Bikram yoga is similar to other yoga sessions in meeting the requirements for moderate intensity exercise. These results are also consistent with another study that warns that weight loss from hot yoga can be mostly from immediate water loss. Nonetheless, yoga in general as a moderate exercise can safely be used for weight maintenance or weight loss if practiced several times per week.