Energy availability, menstrual dysfunction and bone health in sports; an overview of the female athlete triad.

INTRODUCTION: The female athlete triad (FAT) is a serious health-related problem that threatens women who exercise. This condition is an interrelated multifactorial syndrome which includes low energy availability, menstrual cycle disturbances and decreased bone mineral density. OBJECTIVE: To review the major components of the FAT and their relationships, as well as strategies for diagnosis and treatment. METHODS: Articles related to the topic were reviewed through PubMed and SportDiscus databases. RESULTS: Interrelationship between components of the FAT may result in clinical manifestations, including eating disorders, amenorrhea and osteoporosis. Clinical conditions are not always exhibited simultaneously. Prevention is important to minimize complications. Diagnosis and treatment is complicated and often must involve an interdisciplinary therapeutic approach. CONCLUSIONS: Understanding of the disease may be facilitated by a unified framework focusing on energy deficiency. Preventive or early interventions require to increase energy availability through a higher total energy intake or a decrease in energy expenditure trough excessive physical exercise. A healthy lifestyle, and support by parents and coaches should be included. Psychotherapy may be necessary when eating disorders are present.

Introducción: La tríada de la atleta femenina es un importante problema de salud que amenaza a las mujeres que practican ejercicio. Este trastorno constituye un síndrome multifactorial e interrelacionado que incluye una baja disponibilidad de energía, alteraciones del ciclo menstrual y disminución de la densidad mineral ósea. Objetivo: Revisar los componentes de la tríada de la atleta femenina y sus interacciones, así como las estrategias de diagnóstico y tratamiento. Métodos: Se revisaron artículos relacionados con el tema en las bases de datos Pubmed y Sportdiscus. Resultados: La interrelación entre los componentes de la tríada de la atleta femenina puede resultar en manifestaciones clínicas, que incluyen trastornos de la conducta alimentaria, amenorrea y osteoporosis. Estas manifestaciones no siempre se presentan de forma simultánea. La prevención es importante para minimizar las complicaciones. El diagnostico y el tratamiento son complicados y pueden requerir a menudo un abordaje terapéutico multidisciplinar. Conclusiones: El conocimiento de la enfermedad puede facilitarse por el desarrollo de un marco unificado centrado en la deficiencia de energía. Las intervenciones preventivas y tempranas requieren un incremento de la disponibilidad de energía a través de un mayor aporte energético o una reducción del gasto asociado a un ejercicio físico excesivo. Debe incluirse un estilo de vida saludable y el apoyo por parte de padres y entrenadores. La psicoterapia puede ser necesaria si se presentan trastornos alimentarios.

American College of Sports Medicine position stand. The female athlete triad.

The female athlete triad (Triad) refers to the interrelationships among energy availability, menstrual function, and bone mineral density, which may have clinical manifestations including eating disorders, functional hypothalamic amenorrhea, and osteoporosis. With proper nutrition, these same relationships promote robust health. Athletes are distributed along a spectrum between health and disease, and those at the pathological end may not exhibit all these clinical conditions simultaneously. Energy availability is defined as dietary energy intake minus exercise energy expenditure. Low energy availability appears to be the factor that impairs reproductive and skeletal health in the Triad, and it may be inadvertent, intentional, or psychopathological. Most effects appear to occur below an energy availability of 30 kcal.kg(-1) of fat-free mass per day. Restrictive eating behaviors practiced by girls and women in sports or physical activities that emphasize leanness are of special concern. For prevention and early intervention, education of athletes, parents, coaches, trainers, judges, and administrators is a priority. Athletes should be assessed for the Triad at the preparticipation physical and/or annual health screening exam, and whenever an athlete presents with any of the Triad's clinical conditions. Sport administrators should also consider rule changes to discourage unhealthy weight loss practices. A multidisciplinary treatment team should include a physician or other health-care professional, a registered dietitian, and, for athletes with eating disorders, a mental health practitioner. Additional valuable team members may include a certified athletic trainer, an exercise physiologist, and the athlete's coach, parents and other family members. The first aim of treatment for any Triad component is to increase energy availability by increasing energy intake and/or reducing exercise energy expenditure. Nutrition counseling and monitoring are sufficient interventions for many athletes, but eating disorders warrant psychotherapy. Athletes with eating disorders should be required to meet established criteria to continue exercising, and their training and competition may need to be modified. No pharmacological agent adequately restores bone loss or corrects metabolic abnormalities that impair health and performance in athletes with functional hypothalamic amenorrhea.

Modified activity-stress paradigm in an animal model of the female athlete triad.

The exercising woman with nutritional deficits and related menstrual irregularities is at risk of compromising long-term bone health, i.e., the female athlete triad. There is no animal model of the female athlete triad. The purpose of this study was to examine long-term energy restriction in voluntary wheel-running female rats on estrous cycling, bone mineral content, and leptin levels. Twelve female Sprague-Dawley rats (age 34 days) were fed ad libitum and given access to running wheels during an initial 14-wk period, providing baseline and age-related data. Daily collection included dietary intake, body weight, estrous cycling, and voluntary running distance. At 4 mo, rats were randomized into two groups, six restrict-fed rats (70% of ad libitum intake) and six rats continuing as ad libitum-fed controls. Energy intake, energy expenditure, and energy availability (energy intake - energy expenditure) were calculated for each animal. Serum estradiol and leptin concentrations were measured by RIA. Femoral and tibial bone mineral density and bone mineral content (BMC) were determined by dual-energy X-ray absorptiometry. Restrict-fed rats exhibited a decrease in energy availability during Weight Loss and Anestrous phases (P = 0.002). Compared with controls after 12 wk, restrict-fed rats showed reduced concentrations of serum estradiol (P = 0.002) and leptin (P = 0.002), lower ovarian weight (P = 0.002), and decreased femoral (P = 0.041) and tibial (P = 0.05) BMC. Decreased energy availability resulted in anestrus and significant decreases in BMC, estrogen and leptin levels, and body weight. Finally, there is a critical level of energy availability to maintain estrous cycling.