Your menstrual cycle is fueled by your hormones. Your pituitary gland tells your body to release hormones so your body will prepare your womb for possible acceptance of an egg. When the egg is released and not fertilized, the womb sheds its thickened lining and your period starts. This is the beginning of your menstrual cycle, and happens on an average of every 28 days. Exercise can sometimes interrupt this process, changing your menstrual cycle. Exercise can also have a positive influence on menstruation.
Cycle Length And Exercise
The more extensive your exercise routine, the more likely you are to have longer cycles. Cycle length ranges from woman to woman, but athletes who undergo vigorous training may experience very long cycles -- having a period every 60 to 90 days, for example -- or a lack of periods altogether. The absence of periods is called amenorrhea and is defined as going without a period for more than six months. Children's Hospital in Boston's Center for Young Women's Health explains that amenorrhea, combined with a lack of essential nutrients and decreased bone mass can be a dangerous situation for young athletes. This phenomenon, called the Female Athlete Triad, usually means you have lower-than-normal estrogen levels that do not allow you to menstruate but also lower your bone mass, making you more susceptible to bone breaks. The amenorrhea piece of the triad could impact your fertility if your body mass is too low to induce regular ovulation. Cutting back on your level of physical activity may be required to restore regular menstruation.
Pain
Exercising may lessen premenstrual symptoms and can ease the discomfort associated with dysmenorrhea, or painful periods. Working out can combat bloating and other digestive issues that some women face during the week before menstruation; the endorphins released during a workout may also be beneficial to lifting an irritable mood. Dysmenorrhea, or painful periods, is a condition in which a woman experiences pubic bone, back and abdominal pain during the first few days of her menstrual cycle. Headache can also be a symptom of dysmenorrhea. Regular exercise can be a non-medical treatment option for dysmenorrhea.
Health Benefits
One possible health benefit that comes out relationship between exercise and your menstrual cycle is a decreased risk of breast cancer. Breast cancer is a hormonally-responsive disease; the growth rate of your cancerous cells responds to your hormone levels. According to the May 2002 issue of the "American Journal of Epidemiology," women who exercise moderately enough that their cycles are affected, do not undergo the same fluctuations of estrogen as women who bleed monthly. Preliminary studies showed a link between moderate to high levels of exercise and a lower incidence of breast cancer.
Considerations
Menstrual cycles that are overly long or short are not normal and should be checked out by your doctor. Mark your calendar with the first day of your cycle -- the first day of bleeding -- to track your periods, no matter how much you exercise. Speak to your doctor if your cycle length changes for seemingly no reason or if you develop pain or other symptoms that are not usual for you.
References
- Center for Young Women's Health: Sports and Menstrual Periods: The Female Athlete Triad; May 2010.
- "American Journal of Epidemiology"; Physical Activity and Menstrual Cycle Characteristics in Two Prospective Cohorts; Barbara Sternfeld et al.; 2002.
- UpToDate: Patient information: Painful Menstrual Periods (Dysmenorrhea); Roger P. Smith and Andrew M. Kaunitz; September 2010.
- Better Health Channel: Menstruation - Amenorrhoea; September 2009.
