Normal menstruation occurs in cycles of 21 to 35 days. The pattern should not vary by more than five days each month, with periods usually lasting three to seven days. Women who exercise heavily may find that they have little or no menstrual bleeding. Periods may be infrequent, irregular or absent for long periods of time.
Normal menstruation involves a complex relationship of hormones. The brain, pituitary gland and ovaries work together to raise and lower hormone levels. Each month that menstruation occurs, the cycle repeats. Illnesses affecting the brain, pituitary gland or reproductive organs can interfere with the hormone balance, disrupting menstruation. Stress, certain medications (including anabolic steroids used to build muscle) and any hormone medication can also affect the cycle.
Both physical and emotional stress can cause minor and temporary changes in a woman’s cycle. Athletes physically stress their bodies with training. Competition is also emotionally stressful. Thanks to the pressures involved, it is not unusual for a female athlete to experience irregular menstrual cycles.
However, if you are experiencing menstrual irregularities, don’t just write it off as a normal part of exercising. It is important to involve your doctor. If a disease is causing the problem, it should be found and treated.
Long periods of abnormal or absent cycles are linked to low bone density and infertility, which must be managed. The preteen, teen and early twenties are the critical years for achieving peak bone mass. If bones do not develop fully during this time, osteoporosis (low bone density) is likely to develop. Since this condition is harder to treat later in life, spotting problems in young women is critical. Eating disorders are also linked to irregular or missed periods.
Athletic women may develop eating disorders and associated menstrual problems. Abnormal or absent periods can be part of a condition known as the female athlete triad. This is a combination of an eating disorder, abnormal menstrual cycles and low bone density in women who exercise heavily. It happens particularly in sports where appearance is emphasized, such as figure skating, gymnastics and ballet. Women involved in other sports are also at risk.
The triad is related to the drive for perfection and low body fat, and the idea that low weight equals better athletic performance. Peers and coaches may also pressure athletes to maintain a certain weight or body shape.
In fact, eating disorders such as anorexia and bulimia reduce athletic performance. Bone density and fertility are also affected. Serious problems with the heart, kidney and metabolism can develop, requiring time in hospital and special treatment.
It can be hard to tell whether a woman has an eating disorder if she is not significantly underweight. With all eating disorders, there is an obsession with food and a drive to have a low percent of body fat or a low body weight. She may also have an unrealistic body image or feel she is too fat, although she is actually very thin.
Exercise alone cannot cause ongoing abnormal periods. However, if nutrition is inadequate or a woman burns more calories than she takes in, exercise can be part of the problem. If an otherwise healthy woman is menstruating irregularly, a visit to a nutritionist is recommended.
If other medical causes have been ruled out, a close examination of diet and nutrition is necessary. Hormone therapy is of questionable benefit, particularly if an eating disorder is present. It has not been shown to improve bone density. It may also give a false sense of normalcy, and so interfere with proper treatment of an eating disorder.
Your menstrual cycle is a barometer of your health. Changes may indicate something is wrong with your body, or simply that you need to balance aspects of your life including stress, nutrition and exercise. If you are an active woman with irregular periods, do not dismiss it as normal. See your doctor for a general examination, blood analysis and nutrition history. Your doctor may suggest you talk with a nutritionist, and possibly have a bone density test.
Regular exercise and good nutrition are two of the most important ways to ensure good long-term health. Learning how to get the most out of your exercise program with good nutrition makes good health sense.