MENSTRUAL RESPONSE TO RUNNING - NURSING IMPLICATIONS

Overt (length of menstrual cycle, duration of menses, and amount of me nses) and covert (luteal surge indicative of ovulation and length of l uteal phase) menstrual cycle characteristics were studied in a sample of 146 who participated in four levels of running intensity. Menstrual and running data were collected for 4 months or 3 cycles. There was a significant difference among the four groups in duration of menses an d in the amount of menses, with nonrunners having significantly more d ays of menses and larger amounts of menses than the two highest intens ity running groups. However, when a history of skipping menstrual peri ods between menarche and age 18 was controlled, the differences betwee n the groups were not significant. There were no significant differenc es among the four groups in incidence of luteal surge or length of lut eal phase. When runners were compared to nonrunners, runners reported, on average, a shorter luteal phase than nonrunners. This difference r emained when controlling for age and history of skipping menstrual per iods. There was no significant difference be the four groups on incide nce of ovulatory disturbances (anovulation or more than one cycle with a shortened luteal phase). But, when compared to nonrunners, runners were found to have significantly more ovulatory disturbances, The best predictors of the variance in menstrual cycle characteristics were hi story of skipping periods between menarche and age 18, and running ver sus nonrunning.