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The amount and type of exercise a women does can actually have an effect on her menstrual cycle.
“When we exercise, our bodies release stress hormones similar to those released during ‘fight or flight’ scenarios,” explains David Jaspan, DO, Chair of the Department of Obstetrics and Gynecology, Einstein Healthcare Network. “In some women, this can block the production of the hormones that regulate the menstrual cycle.”
This is known as secondary amenorrhea. So why does this happen?
“One reason has to do with critical body mass,” notes Dr. Jaspan. “The reason that is important is because you need a particular amount of fat to be able to create enough of the hormones for menstruation.”
Dr. Jaspan explains that the second reason is actually related to the brain. There is a gland called the hypothalamus, that releases serotonin during stress, which can affect the ability of the pituitary gland to release stimulating hormones that are critical to the menstrual cycle.
Generally speaking, if you have missed your period for about 6 months—including no bleeding, staining or spotting—you should go see your doctor.
“The risk that people need to know about generally happens to young women; we get concerned about overall bone health,” explains Dr. Jaspan. “In very young girls, you look at the potential stunting of growth because the growth plate prematurely closes.”
The good news is, it doesn’t mean you can’t exercise or continue current training regimen. Dr. Jaspan shares that there are dietary modifications and many changes to interval training that can be made. For marathoners in particular, this could involve spacing long runs further apart until the menstrual cycle returns.
“It can return again with the proper care,” Dr. Jaspan reassures. “Birth control pills are an option should the other methods not work.”
Dr. Jaspan notes that in the case of an overweight person there are different reasons why the period could have stopped that don’t involve secondary amenorrhea, and medical attention should be sought sooner.