What is the primary energy source utilized during high-intensity exercise?

During high-intensity exercise, the primary energy source utilized by the body is carbohydrates. This is because carbohydrates can be broken down rapidly to provide energy to the muscles through processes like glycolysis. When physical activity is intense, the demand for quick energy increases, and carbohydrates can be metabolized more efficiently compared to fats or proteins.

Fats, while they are an essential energy source for lower intensity or prolonged exercise, do not provide energy swiftly enough to meet the demands of high-intensity activities. Proteins mainly serve as building blocks for muscle repair and growth, rather than a primary energy source during exercise. Vitamins do not provide energy at all; instead, they play supportive roles in various bodily functions, including energy metabolism. Thus, for high-intensity activities, carbohydrates are favored due to their quick availability and efficiency in generating energy.