• female athlete triad
• energy deficiency

Every year in the USA, 8 million athletes participate in high school sports and 460 000 participate in intercollegiate sports.1 Sport participation is an important vehicle for many adolescents and young adults to achieve recommended levels of physical activity. High school and college athletes are more likely to meet nationally recommended levels of physical activity in comparison to non-athlete peers,2 3 and sports participation confers many health benefits not discussed here.

However, sports participation also can be a risk factor for unhealthy behaviours, high training loads and metabolic disturbances in a subset of vulnerable athletes. As the level of competition increases from high school to college, the duration and intensity of an athlete’s training typically increases. For running sports such as cross country and track and field, the transition from high school to collegiate training may result in a substantial increase in weekly running mileage. Along with this increase in training load, college athletes are exposed to changes in their dietary intake (eg, cooking for themselves or eating in a residence hall), sleep patterns (eg, staying up late …