Which activity primarily uses the ATP-PCr energy system?

The ATP-PCr energy system, also known as the phosphagen system, is primarily involved in providing instantaneous energy for short bursts of high-intensity activities. It relies on the stored ATP (adenosine triphosphate) and phosphocreatine in the muscles to generate energy quickly. This system is most effective during activities lasting up to about 10 seconds, where there is a high demand for power and speed.

Darting from the locker room to the pool represents a high-intensity activity that typically lasts only a few seconds. This movement requires a quick burst of energy, making it ideal for the ATP-PCr energy system, which can rapidly supply energy without the need for oxygen.

In contrast, swimming laps for 30 minutes, participating in a long-distance run, and engaging in yoga sessions involve sustained and lower-intensity efforts over extended periods, which predominantly rely on aerobic energy systems rather than the rapid energy release provided by the ATP-PCr system. Thus, the choice involving darting to the pool accurately reflects an activity that leverages the quick explosive energy provided by the ATP-PCr system.