Background for the Female Athlete Triad
In 1972, Title IX of the Educational Amendment Act, took effect. What followed was an explosion of female participation in athletics. This law has profoundly affected student participation, especially female participation, in athletics from middle school through college. For example, since 1972 male participation in high school athletics has increased by 22%. Female participation has increased by nearly 1000%. While there is a myriad of benefits for girls and women participating in athletics, there are some unique risks that boys and men do not face. In 1992, an association was found between disordered eating, amenorrhea (lack of menstrual cycles) and osteoporosis (low bone density leading to fractures) and athletic activity – especially those types that emphasized e lean physique such as running or dancing. This became known as the Female Athlete Triad.
How are these problems linked?
In order to have normal reproductive function, women must consume an adequate amount of food energy. The amount of energy is measured in calories. Any situation which disrupts the balance between the amount of calories that a woman eats and the number of calories she burns through her activities can interfere with her normal reproductive function.
Inadequate Energy Availability: The first part of the Female Athlete Triad
Inadequate calorie intake
There are four instances that may result in a woman failing to eat enough to support her body functions. The first is unintentional. A woman may simply not realize that she is failing to eat enough to account for all of her activities. This may be due to a lack of nutrition education, errors in calculating her needs or the lack of time or resources to keep up with her training. For some athletes, there is an intentional reduction in the amount that they eat. There is an unfortunate, pervasive but mistaken belief among athletes that increasing calorie intake will REDUCE athletic performance. This is especially common in runners and ballet dancers.
Still other women may have developed abnormal eating behaviors that fail to rise to the level of an eating disorder but are important nevertheless. These includes restrictive eating, binge-eating and or purging, fasting, frequently skipped meals, use of diet pills, laxatives, or diuretics and use of enemas.
Finally, some women have a full blown eating disorder which is characterized by abnormal eating behaviors, an irrational fear of gaining weight, and false beliefs about eating, weight, and shape. Several studies have found that eating disorders are much more common in athletes than in in other women.
Excessive calories being burned
Even if a woman consumes what would ordinarily be considered to be an adequate amount of calories, an increase in her physical activity may simply outpace her consumption. For example, an average 18 year old woman who is not very active may need only 1800 calories a day whereas she may need 3000 or 4000 calories a day if she participates in daily practice for a high school sport.
Stable weight: Don’t be fooled
Some women incorrectly believe that as long as they are not losing weight, then they must be eating enough calories. When energy availability is too low, the body will first reduce the amount of energy that is used for cellular maintenance, temperature regulation, growth, and reproduction. This compensation will maintain weight at the expense of these other body functions. A good rule of thumb is that weight loss is always a sign of low energy availability but low energy availability does not always cause weight loss.
Energy and the brain
There are parts of the brain that are responsible for producing electrical signals which control the reproductive system. The signals, which occur in periodic pulses are necessary for proper hormone production which in turn is what allows ovulation to occur in its normal monthly pattern. These areas of the brain are very sensitive to the amount of energy available in the body. If a woman decreases the amount of calories she eats or increases the amount of exercise she performs, these brain areas will shut down their electric pulses and cause a cascade of effects which result in the failure to ovulate and therefore the failure to have periods.
Lack of menstrual periods – The second part of the Female Athlete Triad
When the ovaries are working correctly, and ovulation is occurring, the ovaries are also producing hormones; estrogen before ovulation and both estrogen and progesterone after ovulation. These two hormones are responsible for thickening the uterine lining and then preparing it for a possible pregnancy. In the absence of a pregnancy, the hormone levels drop and this triggers the period. So it turns out that the lack of a regular period can be a sensitive indicator of low energy availability causing interference with the reproductive system.
Depending on their age, women with low energy availability may fail to ever start having periods (called primary amenorrhea) or may cause the periods to stop coming after they have begun (secondary amenorrhea). These problems are far more common in athletes. For example, less than 1% of all women have primary amenorrhea but it happens in 10% of ballet dancers and 20% of gymnasts. Secondary amenorrhea occurs in 2-5% of all women but in 65% of distance runners and almost 70% of dancers.
Infertility and the Female Athlete Triad
Failure to ovulate is a common cause for infertility. Women who are no longer in school may not think of themselves as athletes but many participate in athletic activities such as running, biking, swimming and dancing. These women have the same risks for developing the Triad as school age girls and women. As such, they may need to assess their calories balance and energy availability if they are not showing evidence for ovulation and/or having infrequent or absent periods.
Bone health – The third part of the Female Athlete Triad
So what does it matter if women get their periods? Not many high school students are trying to get pregnant after all. While the periods themselves (the actual bleeding) are not important, the hormone production which causes the periods is very important for developing and maintaining the strength of bones. Estrogen production from the ovaries is critically important for building bone strength. Athletes who are not ovulating are at greater risk for developing stress fractures which may prevent her from being able to participate in athletics. Since 90% of the mass of bones in women occurs before the age of 20, those women who don’t reach their peak bone strength will be at greater risk for developing osteoporosis and bone fractures later in life – a major source disability and even death in older women.
Cardiovascular Health – The fourth part of the Female Athlete Triad
We normally think of athletes as having a low risk for cardiovascular disease. For the most part this is true. However, female athletes who are not getting their periods regularly are at higher risk for problems with their arteries. These problems result in abnormal blood vessel constriction and the development of blockages in the blood vessels which can lead to heart attacks and strokes in otherwise young healthy women.
How is Female Athlete Triad Treated?
The treatment of Female Athlete Triad is to restore energy availability by either reducing the amount or intensity of exercise or by increasing the amount of calories that a woman consumes. This is not an easy prescription. Athletes, especially competitive athletes do not want to cut back on their training. There are many roadblocks to getting women to increase their calorie intake. Women with eating disorders should be treated appropriately by a qualified mental health professional.
It will take time to see a return to a healthy system. Whereas recovery of energy availability can occur in days to weeks, recovery of ovulation and periods may take months. Improved bone health may take years.
The wrong thing to do is to cover up the problem by using birth control pills, patches or contraceptive rings. It will not prevent the underlying and health issues and will give a woman a false sense of security by causing her to get periods.