Carbohydrates are the primary fuel for sport. Teenage athletes who restrict carbohydrates to lose weight often see drops in performance, concentration, and recovery quality. A meal with complex carbohydrates and moderate protein two to three hours before training optimises energy availability.
Iron and calcium are the two micronutrients most commonly deficient in teenage athletes. Girls who are menstruating and training heavily are at particularly high risk of iron deficiency. Regular blood tests are reasonable for active teenagers who show signs of fatigue.