Question

What is the effect on muscle atp and creatine phosphate (crp) when an athlete performs very-high-intensity exercise for a very short period of time (e.g., 10 seconds)?

Answer 1

Creatine phosphate is one of the energy source stored in muscle. Creatine phosphate is easy to use so it mostly used for high-intensity exercise. But the amount of creatine phosphate stored is limited, so it will decline substantially.
Unlike creatine, the amount of ATP is much higher so it declines slower.