ACSM Personal Trainer Certification Practice Exam 2025 - Free Personal Trainer Practice Questions and Study Guide

The ATP-CP energy system, also known as the phosphagen system, is primarily utilized during high-intensity, short-duration activities. This system provides immediate energy for activities that last from about 0 to 10 seconds, relying on stored adenosine triphosphate (ATP) and creatine phosphate (CP) within the muscles.

In the context of the options provided, a 100-meter sprint is an ideal representation of the ATP-CP energy system since it typically lasts around 10 seconds for elite sprinters and involves maximal effort. During this time, the body primarily uses the ATP and CP stored in the muscles for quick bursts of power without requiring oxygen, making it an anaerobic activity.

Long-distance running, a marathon, and yoga sessions depend mainly on aerobic energy systems, which rely on oxygen and take place over longer durations. These activities involve lower intensity and longer time frames, which utilize different metabolic pathways for energy, contrasting sharply with the immediate and explosive nature of the ATP-CP system. Thus, the 100-meter sprint is the best representation of anaerobic energy production through the ATP-CP system.