Variations in performance in simple muscle tests at different phases of the menstrual cycle.

The effect of the menstrual cycle on the performance of women in sporting activities is a very confused subject. In this study, performances in simple muscle tests--the handgrip and standing long jump, were studied at three phases of the menstrual cycle--menstrual (day 1-4), follicular (day 12-14) and luteal (day 19-21). Within subject paired "t" testing showed that in the handgrip test, performance was significantly superior during the menstrual phase than those during both the follicular and luteal phases. In the standing long jump test, performance was again superior during the menstrual phase, although not significantly with respect to the luteal phase. This finding is discussed in terms of the reported effects of the menstrual cycle on sporting performance, the variation in the types of exercise, and the possible role of the female sex hormones.