I am a 24-year-old female and an avid runner. I currently run 70 minutes a day on weekdays, 80-90 minutes on Saturdays and take Sundays off. I also do about 30 minutes of strength and core training six days a week.
I’m 5’4” and weigh between 118-120 pounds. I had secondary amenorrhea for five years before starting birth control to correct the problem. Am I running too much? Is this routine going to cause more harm than good to my heart and the rest of my body?
You raise some critical questions for young women who exercise for health and for competition. The issues you raise are lumped together under the label of female athlete triad. This was first described in the early 90’s as the association of amenorrhea, stress fracture, and disordered eating. We now know it as a spectrum of problems that revolve around a common denominator of energy balance. Energy balance reflects the amount of calorie taken in during the day and the amount of calorie burned in activities of daily living, keeping the body functions operating, and exercise. So an athlete might be in an energy deficit from not eating enough food or from exercising too much for the amount of food eaten. The bottom line is that even with a normal weight for height, as you have, you can still be energy deficient. The solution to the problem is to either eat more, exercise less, or some combination. Anne Loucks has devoted much of her career to this issue and simply states that to stay in energy balance and exercise hard, a woman should “eat like a man.”
The second critical issue for you is bone health. I think of the menstrual cycle as a measure of nutritional health, in addition to a measure of reproductive health, and a normal menstrual cycle with its associated hormones is critical to bone mass deposition and fracture risk in later life. If the energy balance is not on the positive side, the systems that promote the menstrual cycle shut down leaving a woman with secondary amenorrhea. This is called Functional Hypothalamic Amenorrhea and the menstrual cycles usually return when the energy balance is favorable. Functional Hypothalamic Amenorrhea is a diagnosis of exclusion and all other causes of secondary amenorrhea should be excluded. While it is common to use the oral contraceptive pill in Functional Hypothalamic Amenorrhea, the pill does not treat the condition or promote bone health.
There is not one simple answer for you, as exercise is an important part of your life and health. Ideally, you can find a balance between exercise and diet that allows your periods to return, but you would need to be off the pill to see if your periods return (make sure you find an alternate method of birth control if needed). The answer may be as simple as increasing your meal portions a bit and adding mid-morning and midafternoon snacks. More likely the solution will require a combination of increased calories and decreased exercise. I would suggest as a starting point cutting back the runs to 60 minutes on Monday, Wednesday, and Friday, 30 minutes on Tuesday and Thursday, and 70-80 minutes on Saturday; and cutting the core exercises to 3 times a week; along with an increase in calorie intake. You can then adjust food intake and exercise to allow your periods to come regularly and protect your bone health along with your heart health.
I hope this helps.
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