The female athlete triad (triad) refers to the co-occurrence of three interrelated conditions: low energy availability, menstrual dysfunction, and low bone-mineral density Factors within sport and exercise environments can increase the risk of developing these conditions. Though the prevalence of the full triad is low, many girls and women will experience one or two of the conditions, which can increase their risk of developing the triad. The triad represents a significant health concern, as it can lead to serious and long-lasting health consequences.
The prevalence of low energy availability has not been well documented. However, estimates of clinical EDs, which may contribute to low energy age-group matched controls, lower than normal levels of estrogen, history of deficient nutrition, and previous bone fractures. Low BMD can result from insufficient accumulation of bone mineral during childhood and adolescence or from bone mineral loss during adulthood.
Originally, the triad included disordered eating, amenorrhea, and osteoporosis. However, in 2007, the American College of Sports Medicine revised their position and redefined the triad as low energy availability, menstrual dysfunction, and low bone mineral density (BMD). Low energy availability refers to the amount of energy after exercise or training that is available for physical functioning and may result from excessive exercise, insufficient caloric intake, or other methods of purging, such as laxatives or vomiting. Eating disorders (EDs), including anorexia nervosa (AN), bulimia nervosa (BN), and eating disorders not otherwise specified (EDNOS) may be present and contribute to low energy availability. However, low energy availability can be present without EDs.
Menstrual dysfunction, the second defining condition of the triad, includes primary amenorrhea (delay of menarche), secondary amenorrhea (absence of menstrual cycle, after menarche, for more than three consecutive months) and oligomenorrhea (more than 35 days between menstrual cycles). Abnormal menstrual functioning often results from low energy availability and can contribute to low BMD. Low BMD is defined as a BMD of at least one standard unit lower than availability, range between 0% and 13.4% among college and elite athletes. Prevalence of subclinical levels of disordered eating is much higher, though rates of specific pathogenic weight-control behaviors vary widely. For example, few athletes report using laxatives or diuretics or engaging in self-induced vomiting, but many diet and exercise excessively. Menstrual dysfunction, a product of low energy availability, ranges between 16.6% and 54% among high school athletes and up to 63.9% among college athletes. Low BMD has been found in up to 21.8% of high school athletes and 11% of elite athletes.
Prevalence estimates of the co-occurrence of all three conditions are lacking. Several studies using the original, more narrowly defined, criteria report rates of 1.2% (high school), 2.7% (college) and 4.3% (elite). In a study using the current ACSM guidelines (2007), the triad was found among 15.9% of college runners. When considering the presence of two of the three conditions, prevalence rates can range up to 18% among high school athletes and 26.9% among elite athletes. The presence of any of these conditions may increase the risk of developing the full triad.
Numerous factors can increase female athletes’ risk for developing triad conditions. Distorted attitudes toward food, eating, and body weight and shape are associated with unhealthy eating and weight control behaviors that can create low energy availability. Athletes in sports that emphasize leanness, low body weight, or appearance, such as distance running, gymnastics, or dance, may be more likely to experience pressures from coaches, teammates, family, and other sport personnel (e.g., judges) about body size or shape. Such stressors may lead athletes to restrict caloric intake and exercise excessively.
Evidence also suggests that sport participation at an elite competitive level increases risk of the triad. Pressure and expectations to consistently perform and achieve at a high level often increase among elite-level athletes. Moreover, there may be serious consequences for poor performance for elite athletes. For example, losing a spot on the national team or losing a sponsorship or endorsement may significantly impact an athlete’s livelihood. Thus, athletes competing at elite levels are not only likely to engage in extensive physical training but also may be susceptible to disturbed body image and weight-related pressures, placing them at increased risk for low energy availability.
All three triad conditions put female athletes at risk for a number of negative health consequences. Disordered eating behaviors, which can contribute to low energy availability, are associated with low self-esteem, anxiety, depression, and a myriad of physical health problems, such as cardiovascular problems, constipation, electrolyte imbalance, muscle cramps, or muscle weakness). Menstrual dysfunction can increase the risk of infertility and result in muscular problems and decreases in BMD. Menstrual irregularities and low BMD increases the risk of stress fractures.
Screening and Prevention
The American College of Sports Medicine recommends screening for the triad during preparticipation and annual health screenings. Additionally, female athletes who present with one triad condition should be screened for the other two. The Female Athlete Triad Pre-Participation Evaluation (Triad PPE), available from the Female Athlete Triad Coalition, can be used to assess eating habits and attitudes, weight and menstrual histories, and history of stress fractures. Potential low BMD can be evaluated via dual-energy X-ray absorptiometry (DXA) when there is a history of low estrogen, disordered eating, or history of stress fractures.
To reduce the risk of the triad, coaches, administrators, and sports medicine professionals can create body-healthy environments by avoiding weigh-ins, weight logs, and weight-related joking, as well as pressures to achieve an unrealistic body size or shape. Moreover, sport governing bodies can promote healthy sport environments by providing triad education and training to officials, coaches, and athletes. Prevention is important because treatment can be challenging; for example, treatment may not result in restoration of normal levels of BMD and ED recovery rates are low. Education, increased awareness, and early interventions are important steps in triad prevention.