The majority of girls and women derive significant health benefits from regular physical activity without incurring health risks(50,93,103). They should be encouraged to be physically active at all phases of their lives. If injuries or medical problems develop, they should be promptly identified and treated by professionals knowledgeable in the care of active women.
In 1992 the Female Athlete Triad was the focus of a consensus conference called by The Task Force on Women's Issues of the American College of Sports Medicine (141). The three components of the Triad are:
1. Disordered eating. Disordered eating refers to a wide spectrum of harmful and often ineffective eating behaviors used in attempts to lose weight or achieve a lean appearance. The spectrum of behaviors ranges in severity from restricting food intake, to binging and purging, to the DSM-IV defined disorders of anorexia nervosa and bulimia nervosa(1,2,44,61,110,111). Disordered eating behaviors can result in short and long term morbidity, decreased performance, amenorrhea, and even mortality(36,49,52,94).
2. Amenorrhea. Primary amenorrhea (delayed menarche) is the absence of menstruation by age 16 in a girl with secondary sex characteristics(119). Secondary amenorrhea is the absence of three or more consecutive menstrual cycles after menarche(76,82,92,118,119).Amenorrhea associated with exercise or anorexia nervosa is hypothalamic in origin (8,77,129). Hypothalamic amenorrhea results in decreased ovarian hormone production and hypoestrogenemia similar to menopause. Both hypothalamic amenorrhea and menopause are associated with decreased
bone mineral density(6,10,19,28,30,84,85,103,104).
3. Osteoporosis. Osteoporosis is a disease characterized by low bone mass and
microarchitectural deterioration of bone tissue leading to enhanced skeletal fragility and increased risk of fracture(10). An expert panel convened by the World Health Organization has established the following diagnostic criteria(65).
A. Normal: bone mineral density (BMD) that is no more than 1 Standard Deviation (SD)below the mean of young adults.
B. Osteopenia: BMD between 1 and 2.5 SD below the mean of young adults.
C. Osteoporosis: BMD more than 2.5 SD below the mean of young adults.
D. Severe osteoporosis: BMD more than 2.5 SD below the mean of young adults plus one or more fragility fractures.The principal cause of premenopausal osteoporosis in active women is decreased ovarian hormone production and hypoestrogenemia as a result of hypothalamic amenorrhea(6,20,28,30,72,84,85,104).