The primary purpose of carbohydrates in an athlete's diet is to serve as the main source of energy for performance. Carbohydrates are stored in the body as glycogen, which is readily available during exercise, especially for high-intensity activities. Adequate carbohydrate intake helps athletes maintain optimal energy levels and endurance, crucial for peak performance. Moreover, carbohydrates can aid in recovery by replenishing glycogen stores post-exercise. It's vital to consume the right types and amounts of carbohydrates to fuel both endurance and strength training.