Bikram yoga involves 26 poses performed in a room heated to 40°C ( 105°F ) Typical sessions just an hour and advocates say it improves mindfulness , flexibility , strength , muscle tone and general fitness . 20 volunteers took part in a new study to monitor body temperatures . Experts warn one man 's temperature reached 40°C/105°F putting him at risk of heat exhaustion and heat stroke .
Bikram yoga involves 26 poses performed in a room heated to 40°C ( 105°F ) Typical sessions last 90 minutes and advocates say it improves mindfulness , flexibility , strength , muscle tone and general fitness . 20 volunteers took part in a new study to monitor body temperatures . Experts warn one man 's temperature reached 40°C/105°F putting him at risk of heat exhaustion and heat stroke .