Physical Activity and Menstrual Cycle Characteristics in Two Prospective Cohorts

摘要: Relations between physical activity and prospectively collected menstrual cycle characteristics were examined in two large cohorts. One cohort consisted of women employed the semiconductor industry 1989 who participated a prospective study reproductive outcomes (n = 367). The other living Tecumseh, Michigan, completed both 1992-1993 1993-1994 examinations for Michigan Bone Health Study 328). Mean length, variability mean bleed length calculated from daily diaries (Semiconductor cohort) or monthly calendars (Michigan median five 11 cycles, respectively. Physical was assessed by self-report at baseline expressed as metabolic equivalent-minutes per week. In Semiconductor study, also reported minutes vigorous exercise their diaries. cohort, total activity, recreational positively associated with length. magnitude these associations declined body mass index increased. only repeated-measures analysis. These findings lend modest support to hypothesis that moderate levels can lengthen cycle.