Certified Personal Trainer (NSCA) Practice Exam

For a balanced diet, which macronutrient should primarily provide energy for endurance athletes?

1. Proteins

2. Carbohydrates

3. Fats

4. Vitamins

The correct answer is: Carbohydrates

Carbohydrates are the primary source of energy for endurance athletes due to their ability to be quickly broken down into glucose, which can easily be utilized by the body during prolonged and intense exercise. When engaged in endurance activities like long-distance running, cycling, or swimming, athletes require a readily available energy source to sustain their performance. Carbohydrates not only replenish glycogen stores in muscles and the liver, but they also help to maintain blood sugar levels, preventing fatigue and optimizing performance. Fats, while also a significant source of energy, are typically utilized during lower-intensity activities or once glycogen stores become depleted. Proteins mainly serve other roles, such as tissue repair and muscle building, rather than being a primary energy source. Vitamins, on the other hand, play essential roles in various metabolic processes but do not provide caloric energy. Therefore, for endurance athletes aiming for optimal performance, a diet rich in carbohydrates is crucial to support their energy needs.