Which substrate(s)is/are primarily used to fuel exercise at 70% VO2 max or higher?
A)glucose
B)fatty acids
C)creatine phosphate
D)glucose and fatty acids
E)fatty acids and creatine phosphate

Question

Which substrate(s)is/are primarily used to fuel exercise at 70% VO2 max or higher?​
A)​glucose
B)fatty acids
C)creatine phosphate
D)glucose and fatty acids
E)​fatty acids and creatine phosphate

Quizplus · Accepted Answer

At exercise intensities of 70% VO2 max or higher, the body primarily relies on glucose as its main energy source through glycolysis and the breakdown of stored glycogen. This is because glucose metabolism can provide ATP quickly and without the need for oxygen, which is important during high-intensity exercise when oxygen delivery may not be able to keep up with demand. While fatty acids can also be used for energy during exercise, they require more oxygen and are therefore more useful at lower exercise intensities. Creatine phosphate is a rapidly available energy source but can only provide energy for short bursts of activity and is quickly depleted.

Which Substrate(s)is/are Primarily Used to Fuel Exercise at 70% VO2