Heart rate and core temperature responses during basic yoga compared to hot yoga

Abstract

This study was designed to examine the differences in heart rate and core temperature between hot yoga and basic yoga classes. Twenty subjects (4 males, 16 females) performed a VO2max test using the Bruce protocol. Additionally, subjects completed a 60 minute basic yoga class and a 60 minute hot yoga class using identical poses. Both classes were taught by the same instructor. Each yoga class consisted of a 5-minute warm-up, a 40-minute exercise session, and a 10-minute cool-down. During the yoga sessions core temperature was measured at the beginning of the class, every 5 minutes during the class, and at the end of the class using a Cor Temp Ingestible Core Body Temperature Sensor. Heart rate was measured each minute of both yoga sessions by radiotelemetry. At the end of each yoga session, subjects rated their perceived effort using the 6-20 Borg scale. There was a significant difference in RPE, for the hot yoga class compared to the basic yoga class. There were no significant differences in heart rate or core temperature responses between yoga sessions. Based upon these results it appears that hot yoga does not result in unsafe core temperature or heart rate responses.