Which type of exercise primarily utilizes glycogen stores for energy?

High-intensity interval training (HIIT) primarily utilizes glycogen stores for energy due to the nature of its intensity and duration. During HIIT, the body engages in short bursts of maximum effort followed by recovery periods. This style of exercise rapidly depletes available energy sources, and glycogen, stored in the muscles and liver, becomes the primary fuel for such high-intensity efforts.

At this intensity level, the body requires quick energy production that glycogen can provide, as it is readily accessible for immediate use through anaerobic metabolism. This is in contrast to lower-intensity activities, where the body often relies more on fat oxidation for energy due to the longer duration and lower demand for immediate energy supply.

Therefore, HIIT serves as an effective workout for tapping into glycogen reserves, making it distinctly beneficial for activities that require short, explosive movements.