Which of the following best defines anaerobic activity?

Anaerobic activity is best defined as short, highly intense activities that occur without the presence of oxygen. This type of exercise relies primarily on energy sources that are stored in the muscles, such as creatine phosphate and glycogen, rather than oxygen intake. It typically involves high-effort bursts of activity, such as sprinting, weightlifting, or high-intensity interval training, which can be performed for a brief duration due to the limited supply of these energy sources.

The nature of anaerobic activities distinguishes them from aerobic activities, which depend on oxygen consumption and are generally sustained for longer durations. Therefore, anaerobic exercises are characterized by their intensity and the body's reliance on energy systems that do not use oxygen in significant amounts.