Let’s be perfectly clear: in almost every circumstance, exercise can only help your fertility – it helps you stay in good physical shape, regulates your hormone levels, and releases endorphins to keep happy baby thoughts in your mind as you try to conceive.
If however, you are an Olympic-level athlete whose morning isn’t complete without a quick marathon or two, over-exercise that affects your fertility is a very real thing.
How can too much exercise inhibit fertility?
While exercise is normally beneficial, under extreme circumstances, you can put your body under and undue amount of stress that affects your hormone levels. Hormones are responsible for regulating your menstrual cycle, so throwing your hormone levels out of whack can interfere with normal menstrual functioning.
Another main concern with over-exercising and fertility is a lack of body weight, or body fat, necessary to regulate hormone levels and ensure a healthy ovulation each cycle. Women with a body fat percentage of less than 18% may have increased trouble conceiving, as their deficiency of fat prevents their hormones from functioning normally, and their eggs are not able to mature and ovulate properly. Although most women who experience ovulatory problems due to a low body fat percentage also have a low BMI, women who engage in a lot of strength training may have a body fat percentage that is too low to conceive, while still having a weight that puts them in the normal BMI range.
Women who are dieting to lose weight or have an eating disorder may also experience ovulatory problems due to a lack of weight, a problem compounded by over-exercise.
How does body fat affect fertility?
Women who are underweight are more likely to have low estrogen levels, which can prevent eggs from maturing, and ovulation from occurring. Being underweight can also make it more difficult to support a pregnancy, and some theorize that a woman who is significantly underweight may experience difficulty ovulating as her body’s biological reaction to her not getting enough nutrients to help a healthy baby develop.
Women who enter pregnancy with a low BMI also must gain more weight throughout the nine months, which isn’t always as easy said than done, and the rapid weight gain can place a lot of uncomfortable stress on the body.
How much exercise is too much exercise? The amount of exercise that places your fertility at risk is unclear, and varies from woman-to-woman. The Mayo Clinic suggests that women who are trying to conceive avoid working out for more than seven hours each week. Other research indicates that working out every day of the week without a break can also be harmful for fertility.
You are the best judge of how much exercise is too much (though your healthcare provider will surely be able to chime in as well), so it’s imperative to trust yourself. It’s important to get a healthy amount of exercise to maximize your fertility and prepare your body for pregnancy–just take a break from running yourself into the ground day in and day out for the time being.
