Zelda is a marathon runner. She completes the marathon in 2 hours and 30 minutes. Which of the following is true regarding her fuel use during the marathon?

Question

Quizplus · Accepted Answer

Amino acids may supply up to 15% of energy needs. This is because during prolonged exercise, the body may break down muscle protein for energy if adequate carbohydrate stores are not available. However, it is unlikely that Zelda would completely deplete her glycogen stores during a 2-hour and 30-minute marathon, so option A is false. Option B is also false because during a marathon, the majority of ATP production comes from aerobic metabolism, not anaerobic glucose breakdown. Option C is also false because the intensity of a marathon is not considered "intense muscular activity."

Zelda Is a Marathon Runner