What does a higher intake of carbohydrates during endurance exercise primarily influence?

A higher intake of carbohydrates during endurance exercise primarily influences increased glycogen availability, which is crucial for maintaining performance. Glycogen serves as a key energy source during prolonged physical activities, especially when the demand for energy is high.

When carbohydrates are consumed, they are stored in the muscles and liver as glycogen. During endurance exercises, such as running or cycling, the body taps into these glycogen stores to provide the necessary energy. A greater availability of glycogen allows athletes to sustain their performance for longer durations, delay fatigue, and maintain optimal intensity levels throughout the exercise.

This enhancement in glycogen stores directly boosts the body's ability to endure prolonged activity and manage energy expenditure more efficiently. In contrast, though carbohydrates can influence factors like muscle recovery and protein synthesis indirectly, their primary and most significant role during endurance activities is to ensure an ample supply of glycogen.