Which nutrient is primarily responsible for providing energy during intense exercise?

The correct choice is carbohydrates because they are the body's preferred source of energy, especially during intense physical activity. When engaging in strenuous exercises, the body relies heavily on glycogen, which is stored in the muscles and liver, for quick energy. Carbohydrates are broken down into glucose, which is readily used by your muscles during high-intensity workouts. This rapid availability of energy is crucial for performance in exercises that require quick bursts of strength or endurance.

Fats, while also a source of energy, are primarily utilized during lower-intensity activities and are slower to break down compared to carbohydrates. Proteins mainly serve as building blocks for muscles and are not a primary energy source during physical activity but can be utilized if carbohydrates are low. Water is essential for hydration and bodily functions but does not provide energy directly. Therefore, carbohydrates are specifically key for fueling the body during intense exercise.