After the first 15 minutes of a 10-km run, the major energy requirements of the leg muscles are supplied by
A) preformed ATP.
B) glycolysis.
C) oxidative metabolism.
D) pyruvate and lactate.
E) the high-protein drink consumed right before the run.

Question

Quizplus · Accepted Answer

After the first 15 minutes of a 10-km run, the major energy requirements of the leg muscles are supplied by oxidative metabolism. Glycolysis and preformed ATP provide energy for the initial stages of the run, but for endurance activities like long-distance running, oxidative metabolism becomes the primary energy source as it is more efficient at producing ATP. Pyruvate and lactate are byproducts of glycolysis, but they do not provide significant energy during the later stages of a 10-km run. Consuming a high-protein drink right before a run may provide some energy, but it is not the primary energy source for the leg muscles during the run.

After the First 15 Minutes of a 10-Km Run, the Major