Cardiovascular responses to sustained isometric hand grip during different phases of menstrual cycle- A cross-sectional study

Introduction: The endogenous gonadal hormones accompanying the menstrual cycle affect the cardiovascular responses to a bout of static isometric exercise. The uncertainty over the consensus as to which phase of menstrual cycle poses greater cardiovascular stress on the female was a question often unanswered. Aim: The aim of the present study was to assess the influence different phases of menstrual cycle on cardiovascular responses like heart rate, blood pressure, rate pressure product to static isometric handgrip exercise. Materials and Methods: Thirty eumenorrhic females were examined after using a hand grip dynamometer during the follicular and luteal phases of menstrual cycle. Statistical Analysis: Data was analysed statistically using student’s paired t-test. Results: It was observed that the baseline values of heart rate in follicular phase was (78.8 ±7.48) while in luteal (84 ± 8.17), SBP in follicular phase (113.9 ± 6.63) while luteal phase (115.8 ±5.91), DBP was (72.8 ±6.90) in the follicular phase and (76.5 ± 6.82) in the luteal phase. MVC at 30% was maintained for 1, 2 and 4 mins and it was observed that all the values of HR, SBP and DBP were higher in the luteal phase. The rate of fall to baseline for all the cardiovascular parameters i.e.HR, SBP and DBP were higher in the follicular phase compared to the luteal phase. Conclusion: The results suggest a greater sympathetic activity during the luteal phase to a bout of static isometric exercise hence it can be inferred that the sex steroids lend themselves to an interaction with the ANS indirectly reflecting in cardiovascular system functioning.