Effect of female sex hormones on cardiorespiratory parameters

INTRODUCTION: Female sex hormones, estrogen and progesterone regulate various phases of the menstrual cycle. Hormonal changes tend to affect various parameters of physical fitness. Maximum oxygen uptake (VO(2) max) is a measure of aerobic power. This study was planned to assess effect of different phases of menstrual cycle on cardiorespiratory parameters like pulse rate, respiratory rate and VO(2) max. METHODS: 100 female medical students in the age group of 17-22 years were studied for three consecutive menstrual cycles. Weight, resting pulse rate, respiratory rate and VO(2) max were measured during premenstrual phase (20(th)-25(th) day) and postmenstrual phase (5(th) to 10(th) day). RESULTS: It was observed that there was a significant increase in body weight, pulse rate, and respiratory rate during premenstrual phase. There was a decrease in VO(2) max during the premenstrual phase. CONCLUSION: This study indicates that there is decreased cardio-respiratory efficiency during premenstrual phase.