Effects of High-Intensity Interval Aerobic Exercise on Heart Rate Variability and Blood Metabolic Markers Across Different Phases of the Menstrual Cycle in Healthy Adult Women

OBJECTIVES The purpose of this study was to analyze the effects of high-intensity interval aerobic exercise (HIIAE) on heart rate variability (HRV) and blood metabolism-related indicators according to menstrual cycle phases in healthy adult women.METHODS Ten healthy adult women with normal menstrual cycles between 21 and 35 days were classified into menstrual phase(MP), follicular phase(FP), ovulation phase(OP) and luteal phase(LP) using a crossover design. HIIAE was performed during each different phase of the menstrual cycle. Heart rate variability (SDNN, LF, HF, LF/HF ratio) and metabolic indices (TG, BL) were measured before, immediately after (IA), and 30 minutes (30-min) following HIIAE.RESULTS SDNN, LF and HF were significantly decreased at IA in each different phase of the menstrual cycle compared to before, and significantly recovered at 30-min. LF/HF ratio was significantly increased at IA compared to before, and significantly decreased at 30-min compared to IA in FP, OP and LP. TG was significantly increased in IA compared to before in the MP, and significantly decreased at 30-min. BL was significantly increased at IA compared to before, and significantly decreased at 30-min compared to before in all menstrual phases.CONCLUSIONS Heart rate variability and metabolism-related indicators were mostly responded at IA in each different phase of the menstrual cycle, and recovered at 30-min. However, the same effect was not observed for heart rate variability and metabolic indices. Therefore, the results of this study suggest that menstrual cycle should be considered during HIIAE in healthy adult women.