Q: For years now, my period has been irregular. My gynecologist told me not to worry because everything seems to be fine. Recently, though, my cycle became regular when I stopped working out. Are my workouts affecting my menstrual cycle?
Many female dancers and athletes who play sports associated with leanness – like running and gymnastics – experience oligomenorrhea, or irregular menstrual cycles. Some even develop amenorrhea, the complete cessation of menstruation. There are several theories as to why this happens.
One theory is that when a woman’s body fat drops below a level adequate to support a baby, her periods stop in order to prevent her from getting pregnant. The problem with this theory is that physically active women with different levels of body fat experience similar symptoms of menstrual irregularity.
Another possibility is that an imbalance in energy – you’re burning more calories through exercise than you’re eating – may be causing the problem. That should mean that your cycle will regulate if you cut back on your exercise (as it did for you). Or, if you don’t want to cut back on your workouts, eating more calories also may regulate your cycle.
Along with many other unanswered questions about exercise and the menstrual cycle, it is not clear what the long-term effects of irregular cycles may be. It is known, however, that the cessation of menstruation can contribute to bone loss, so if you’re experiencing irregularity make sure you’re getting adequate calcium in your diet.
It’s also important to see a gynecologist or endocrinologist – as you did – to rule out any medical conditions that may have similar symptoms.