An adequate energy intake is essential to optimize exercise performance and adaptations — if one maintains an energy-deficient diet during training, muscle loss, impaired recovery, illness, decreased bone mineral density, poor mood, and menstrual dysfunction can occur.[1] Consuming a hypercaloric diet augments resistance-training-induced increases in muscle mass.[2]
Beyond general energy intake, carbohydrate intake is important because it serves as a primary fuel source over a wide range of exercise intensities, and a robust body of evidence demonstrates that matching carbohydrate availability to exercise demands enhances both prolonged endurance exercise and intermittent high-intensity exercise performance.[3] Additionally, dietary protein intake is essential for the synthesis and repair of muscle tissue and is required after exercise to elicit a positive net protein balance.[4]