What is the difference between aerobic and anaerobic exercise?

Aerobic exercise requires oxygen for fuel and involves activities that can be sustained over longer periods of time, such as running, cycling, and swimming. These activities are performed at a moderate intensity that allows the body to use oxygen efficiently to produce energy. On the other hand, anaerobic exercise occurs without adequate oxygen, engaging the body's energy systems that do not rely on oxygen for energy production, typically involving high-intensity activities like sprinting or heavy weightlifting that are performed for shorter durations.

The distinction provided in the correct answer is fundamental to understanding how the body generates energy under different exercise conditions. The body's energy pathways shift based on the availability of oxygen, which significantly affects performance, endurance, and recovery strategies for athletes.