What is the evidence-based recommendation for carbohydrate intake during prolonged endurance exercise?

The recommendation of 30-60 grams of carbohydrates per hour during prolonged endurance exercise is grounded in extensive research on carbohydrate metabolism and performance. This range has been shown to optimize glycogen utilization and sustain energy levels during endurance activities, which can last for several hours.

During prolonged exercise, the body’s glycogen stores can become depleted, leading to fatigue and diminished performance. Supplementing with carbohydrates in this range helps maintain blood glucose levels and supports continuous energy supply, allowing athletes to perform at higher intensities for longer durations. This intake also aids in the prevention of hypoglycemia, which can occur when the body runs low on available glucose.

Research indicates that consuming less than 30 grams may not provide sufficient energy for effective performance, while consistently exceeding 60 grams may offer diminishing returns or gastrointestinal discomfort for some athletes. Therefore, the 30-60 grams per hour recommendation strikes a balance between maximizing performance benefits and minimizing potential negative effects during endurance events.