Relationship between athletic performance and menstrual cycle.

The female sex steroid hormones have multiple actions on body systems other than the reproductive axis. Female athletes, coaches, medical professionals, and researchers have long been concerned about the potential impact of menstrual cycle fluctuations in these hormones on components of athletic performance. Estrogen is known to affect the cardiovascular system, bone, and the brain; progesterone primarily influences thermoregulation and ventilation. Substrate metabolism is likely altered by both hormones. Net physiological effects can be either opposing or synergistic and are determined by the relative proportions of each. Nevertheless, investigations to date have not consistently demonstrated significant differences in aerobic capacity, anaerobic capacity, aerobic endurance, or muscle strength in any specific menstrual cycle phase. The course of some chronic diseases may vary slightly during the menstrual cycle, but the mechanism is currently unknown. Recent research in underlying hormonal causes for anterior cruciate ligament (ACL) injuries also is not convincing.