Question

during short periods of intense exercise, energy in muscles is primarily derived from:
aerobic respiration
both anaerobic respiration and creatine phosphate breakdown
anaerobic respiration
creatine phosphate breakdown
nuclear reactions

Explanation:

• Aerobic respiration requires oxygen and is more active during prolonged, less - intense exercise.
• Nuclear reactions are not involved in muscle energy production in the human body.
• Creatine phosphate breakdown provides a quick burst of energy (ATP) for very short - term intense activities (first few seconds).
• Anaerobic respiration (glycolysis without oxygen) can also contribute to energy production during short - term intense exercise, especially as creatine phosphate stores are depleted.

Answer:

B. Both anaerobic respiration and creatine phosphate breakdown