Heart rate response during hatha yoga and the effects on health-related physical fitness 2007

The purpose of this study was to investigate the effects of yoga training programs on health-related physical fitness and to measure the heart rate (HR) responses of individuals throughout an actual Hatha yoga class. Two male and six female college students who were enrolled in an intermediate Sivananda yoga class voluntarily participated in this study. Yoga classes lasted 105 minutes and were offered twice a week for eight weeks; participants had to attend at least 50% of the classes. One male and six female participants had their physical fitness tested after the first week of yoga training and again five days after the final yoga class. Aspects of physical fitness tested included: body composition, flexibility, muscular strength, and muscular endurance. Pre and post fitness test results were compared using a paired-samples t-test, with alpha set at 0.05. Only trunk flexibility significantly improved post yoga training (t (6) = -11.12, p 0.005). To measure HR responses to yoga training, HRs of three females and one male were recorded every 30 seconds while participants wore Polar HR monitors during the final yoga class. Mean HRs were highest during sun salutations and lowest during the relaxation pose, savasana. Heart rates for the main Sivananda asanas (excluding locust) ranged from 93 ± 17 beats per minute (BPM) to 106 ± 14 BPM. This study suggests that yoga training approximately once a week can improve hip flexibility but such training is not effective at improving body composition, shoulder flexibility, muscular strength or muscular endurance. This study also shows that HR responses during yoga were highest during warm up exercises and lowest during relaxation exercises; HR responses were moderate during all of the main 12 Sivananda postures