How does carbohydrate availability influence exercise performance?

Carbohydrate availability plays a crucial role in exercise performance, particularly when it comes to sustaining higher exercise intensities. Carbohydrates are a primary source of fuel during both aerobic and anaerobic exercise, and having sufficient glycogen stores allows athletes to maintain greater levels of exertion.

When carbohydrates are readily available, the body can utilize them efficiently for energy production, which is essential during sustained activities like running, cycling, or any high-intensity workouts. Optimizing carbohydrate intake before and during exercise can enhance stamina, delay the onset of fatigue, and potentially lead to improved performance outcomes.

This contrasts with the other options, where decreased carbohydrate availability could lead to reduced energy production and increased risk of fatigue, both of which impair exercise performance rather than enhance it. Similarly, the option concerning muscle mass is not directly impacted by carbohydrate availability during exercise; instead, it's more related to overall dietary protein and calorie intake. Thus, the correct answer highlights the importance of carbohydrates in facilitating greater exercise intensity, showcasing their vital role in sports nutrition and performance.