Which of the following energy sources would provide the majority of the ATP for a person running a 26-mile marathon?

a. Stored ATP

b. Glycolytic catabolism

c. Oxidative catabolism

d. Creatine phosphate

Video transcript

Hi, everyone. Let's take a look at this practice problem together. Which of the following will ensure that a marathon runner has enough energy to finish the race. The answer options are a creatinine B. Creatine phosphate C stored added adipose and datp. So during a marathon, a runner will have sustained muscle contractions for long periods of time. So what source of energy will be used by the muscle cells recall that muscle cells have three main sources of energy and those sources are etp, creatine phosphate and glycogen. That means that we can eliminate options. A and C option C stored adipose recall that adipose tissue is a main site of energy storage when there is excess amounts of energy and option A creatinine. This is a by-product of creatinine phosphate metabolism. So both options A and C are incorrect. Option B, Creatine phosphate. Creatine phosphate provides quick energy and is used rapidly within 10 to 15 seconds. So it won't be a source of energy for the marathon runner to finish the race. So option B is incorrect. The correct answer is etp. So during a marathon, the runner is producing a TP, primarily through aerobic energy or aerobic respiration. This means that the mitochondria is using oxygen to break down nutrients like glucose and fatty acids and that will produce a TP. This is the way most P is produced during long periods of muscle contraction. The correct answer is option. DATP. All right, everyone. I hope you found this helpful and I'll see you soon for the next practice problem.