Which physiological factor increases VO2 max through improved cardiac output?

Which physiological factor increases VO2 max through improved cardiac output?

• A. Increased maximum cardiac output
• B. Increased lactate tolerance
• C. Increased stores of glycogen
• D. Reduced body fat

Answer: (C)

VO2 max represents how much oxygen the body can deliver and use at maximum effort. It depends on central delivery (cardiac output) and how effectively muscles use that oxygen. At peak exercise, VO2 max = maximal cardiac output × (arteriovenous O2 difference). To raise VO2 max by enhancing the delivery side, the body needs a higher maximal cardiac output, which comes from greater stroke volume (and often heart rate) developed with training. So the factor that increases VO2 max through improved cardiac output is increased maximum cardiac output. The other options influence performance in different ways: more glycogen stores help sustain energy during high-intensity work but don’t raise the maximum oxygen delivery; greater lactate tolerance improves work capacity under fatigue, not the ceiling of oxygen uptake; and reduced body fat can improve efficiency but doesn’t directly boost the maximal oxygen delivery capacity.

VO2 max represents how much oxygen the body can deliver and use at maximum effort. It depends on central delivery (cardiac output) and how effectively muscles use that oxygen. At peak exercise, VO2 max = maximal cardiac output × (arteriovenous O2 difference). To raise VO2 max by enhancing the delivery side, the body needs a higher maximal cardiac output, which comes from greater stroke volume (and often heart rate) developed with training. So the factor that increases VO2 max through improved cardiac output is increased maximum cardiac output.

The other options influence performance in different ways: more glycogen stores help sustain energy during high-intensity work but don’t raise the maximum oxygen delivery; greater lactate tolerance improves work capacity under fatigue, not the ceiling of oxygen uptake; and reduced body fat can improve efficiency but doesn’t directly boost the maximal oxygen delivery capacity.