Assessment of bronchial responsiveness on exposure to isometric exercise during different phases of menstrual cycle:...

The present study was planned to assess the effects of gonadal steroids (estrogen and progesterone) on bronchial responsiveness, before and after handgrip exercise, during different phases of menstrual cycle.

In this study, 30 healthy (25-40 years), non-athletic, adult female volunteers were studied. The various pulmonary function parameters (FVC, FEV1, PEFR, FEF 25-75%) were recorded with a spirometer under resting conditions and then within five minutes of cessation of isometric exercise. Recordings were taken during the Menstrual phase (MP), Proliferative phase (PP), and Luteal phase (LP) of menstrual cycle and were confirmed by plasma levels of estrogen and progesterone. The oral temperature was recorded during each phase of the menstrual cycle.

Under resting conditions, the above-mentioned parameters did not reveal significant differences during the three phases. A significant fall was observed only in the Peak Expiratory Flow Rate (PEFR) during all the phases after handgrip, but there was a non-significant decline in the other parameters.

By this study we conclude that the physiological changes in hormone levels during the menstrual cycle are not in themselves associated with changes in airway responsiveness before and after the handgrip test. The general fall seen in the pulmonary parameters could be due to fatigue or psychic factors.