What is the Female Athlete Triad?

The Female Athlete Triad refers to three interrelated health problems seen in females. These problems include: low energy availability, menstrual disorders, and weak bones.  In the extreme, these problems may be expressed as eating disorders, amenorrhea (loss of menstrual periods), and osteoporosis (an increased risk of fractures).

Energy Availability

Low energy availability is the key problem causing the other components of the Triad.  The energy in food is used by the body for several basic processes:  cellular maintenance, warmth, immunity, growth, movement and reproduction.  Energy used for one of these processes is not available for the others.  For athletes, energy availability may be thought of as the amount of today's dietary energy remaining after exercise for the body's other processes.  By reducing their dietary energy intake or by increasing their exercise energy expenditure athletes may lower their energy availability so far that the body's other processes cannot function properly.  Because female athletes tend to eat less than would be expected for their level of physical activity, their diet and exercise habits tend to distribute them along a spectrum of energy availability between energy balance and extreme low energy availability. 

Disordered Eating Habits/Eating Disorders

Although low energy availability may be caused by increasing energy expenditure without any reduction in energy intake, for some athletes disordered eating may be the first step in developing the Triad.  In an effort to improve performance, athletes often try to lose weight or body fat.  Disordered eating by severely limiting food intake, constantly weighing and/or measuring foods, eating secretly, refusing to eat in front of others, and abusing laxatives, impedes performance and results in dehydration, malnourishment, and unhealthy weight loss, as well as psychological difficulties such as food/weight obsession, depression, and anxiety.

Loss of Menstrual Periods (Amenorrhea)

When too little energy is available after exercise, a female athlete's body reduces energy expenditure in other processes, in part by suppressing menstrual function.  Therefore, because energy expenditure during exercise reduces energy availability, female athletes are at increased risk for menstrual disorders.  Female athletes who also restrict their dietary energy intake or who practice disordered eating behaviors are at even higher risk.  It is important to understand, however, that exercise has no suppressive effect on menstrual function beyond the impact of its energy cost on energy availability, and that the disruptive influence of exercise on menstrual function can be prevented by increasing dietary energy intake in compensation for exercise energy expenditure.  Because female athletes are distributed along a spectrum of energy availability, most display a range of infertility problems from imperceptible luteal phase defects to amenorrhea.  In very young athletes, low energy availability may also delay the onset of menstruation. 

Osteoporosis (Weak Bones)

When too little energy is available after exercise, the female athlete's body also reduces energy expenditure by slowing the turnover of bone tissue.  This turnover (resorption of old bone and formation of new bone) is how bone grows and heals, including the routine repair of millions of micro-cracks that occur in everyone's bones every day.  Impairing bone growth is especially harmful for young athletes, because 50% of bone mass accumulates during the teenage years and low bone mass is a major risk factor for fractures.  Low energy availability reduces the rate of bone formation by suppressing metabolic hormones that promote bone formation.  Meanwhile, the loss of regular menstrual cycles often reduces the body's production of estrogen, which normally restrains the rate of bone resorption.  The resulting imbalance, in which resorption exceeds formation, can cause a progressive, irreversible reduction in bone density.  It is important to recognize, however, that an adolescent athlete can fall farther and farther behind her peers in bone density through slow bone formation alone without ever actually losing bone.  Poor eating habits may also decrease the intake of calcium, vitamins, and minerals that the athlete also needs to build and repair bone.  Meanwhile, the intense exercise and physical demands of her sport increase an athlete's risk of stress fractures and other bone-related problems.  Unfortunately, if her condition worsens to the point that she cannot train or compete, she may become depressed and/or eat even less to compensate for the lack of exercise.

What are the risk factors for developing the Triad?

Any factor that increases energy expenditure or reduces energy intake would be considered a risk factor.  These include factors such as: prolonged exercise training to develop greater endurance or to promote weight loss; dieting to lose weight or fat for participation in sports that require a thin body or weight classes, to improve performance, or to improve appearance in revealing uniforms (e.g., swimsuits or bikinis); perfectionist personality traits; decreased eating with family and friends; and the attitude that amenorrhea, excessive exercise, and weight loss are "normal" or even "desired" characteristics of "good athletes."  Because some of these risk factors are inherent in athletics and necessary for athletic success, the identification of low energy availability as a problem is more difficult in the athletic environment.  This further increases the athlete's risk of developing the Female Athlete Triad.

What are the signs of the Triad?

In general, adolescents should be gaining, not losing, lean body mass during their teenage years.  Except when losing body fat under the supervision of a healthcare professional, athletes should eat more, not less, than their sedentary peers.  Therefore, disordered eating, restrictive dieting, binge eating, induced vomiting, and excessive use of laxatives and prolonged exercise are prominent signs of low energy availability.  Physical signs of the Triad include noticeable weight loss, cold hands and feet, dry skin, hair loss, absent or irregular menstrual periods, increased rate of injury, delayed healing time for injuries, and stress fractures.  Emotional signs include mood changes, decreased ability to concentrate, and depression.

Is it normal for female athletes to stop having their menstrual period because they train so hard?

No.  It may be the "norm" in some sports, but it is never healthy, desirable or acceptable.  When menses stop, the body is communicating that something is wrong.  Energy consumption is not meeting the needs of the individual.  Furthermore, if an athlete is over the age of 16 and has not yet started menstruating, she should contact a healthcare professional.  Lack of menstruation can inhibit normal pubertal growth and development.

Why should young female athletes and their families worry about this now?

Eating habits develop early and last a lifetime; it is important to develop good eating habits at an early age.  In addition, the teenage years are the most important ones for the accumulation of peak bone mass, which starts to decline after menopause.  Therefore, lack of good bone health during adolescence will increase the risk of stress fractures in the near term and drastically impair bone health later in life.

What are the consequences of the Triad?

The Triad can harm every aspect of life.  Nutrient deficiencies and fluid/electrolyte imbalance can lead to impaired performance growth and mental functioning as well as an increased risk of fractures and other injuries.  Long-term consequences may include loss of reproductive function and serious medical conditions such as dehydration and starvation.  In some cases, this condition has resulted in death.

How is the Female Athlete Triad treated?

Treatment must address all possible causes of the Triad.  Treatment should include medical, nutritional, and psychological intervention.  Counseling and education regarding eating properly for the amount of energy expended as well as activity modification may be integral parts of the recovery process.  Normal menstruation should be a goal for the athlete.

How can the Triad be prevented?