Question

during 30 seconds of maximal exercise, the PC system is responsible for _______ of energy provision, then approximately _______ of ATP is attributed to fast glycolysis, and then ______ comes from the oxidative system

Answer 1

During maximal exercise, the PC system provides initial energy, fast glycolysis contributes around 70-75% of ATP thereafter for about 90 seconds, and then the oxidative system takes over for extended energy supply.

Step-by-step explanation:

During 30 seconds of maximal exercise, the phosphocreatine (PC) system is responsible for the initial burst of energy provision, supplying ATP for about 8-10 seconds.

After this initial period, approximately 70-75% of ATP is attributed to fast glycolysis, where glycogen is used to make ATP from glucose in the absence of oxygen, which can last up to about 90 seconds. Beyond the peak activity of fast glycolysis, and as exercise continues, ATP comes from the oxidative system, which utilizes oxygen to breakdown glucose into ATP, carbon dioxide, and water.

This system provides about 95% of the ATP required for resting or moderately active muscles and is critical for extended periods of muscle exertion. Aerobic respiration occurs in the mitochondria and is a much more efficient way of producing ATP, although it’s a slower process compared to anaerobic pathways.