Influence of Cycle Menstrual Phases on Cardio-Respiratory Responses to Sub-Maximal Exercise Among Eumenorrheic Young Women

Abstract

Background: Exercising during different phases of the menstrual cycle may result in differential physiological responses due to differential  concentrations of oestrogen and progesterone in these phases. However, there is a dearth of information on the influence of menstrual phase on  physiological responses to sub-maximal exercise in eumenorrheic women. This study therefore examined the influence of menstrual phases on  cardio-respiratory status in eumenorrhoeic women, and their cardio-respiratory responses to sub-maximal exercise.

The methods used in this study involved: Quasi-experimental in which 110 eumenorrhiec undergraduates are involved. They performed sub-  maximal exercise on a treadmill using Bruce Protocol. Axillary temperature, resting heart rate, blood pressure (BP), respiratory rate (RR), rate  pressure products (RPP) body mass index and waist circumference were recorded pre and post exercise using standardised procedures.

The results obtained were: Systolic BP, diastolic BP and body temperature did not differ (p>0.05) across the phases of the menstrual cycle except  for heart rate (p= 0.004) and RPP (p= 0.047) that had the highest values in the luteal phase and the lowest value in the follicular phase. Menstrual  phase showed no significant influence (p>0.05) on systolic BP, diastolic BP, heart rate, body temperature, and respiratory rate and RPP responses to  sub-maximal exercise across phases of the menstrual cycle among eumenorrheic undergraduates.

In conclusions, heart rate and RPP are lowest  during the follicular phase of the menstrual cycle, and there is no difference in cardio-respiratory and body temperature responses to sub-maximal  exercise across the phases.