Interval training improves aerobic capacity by incorporating short bursts of high-intensity exercises followed by periods of lower intensity or rest. This method elevates the heart rate more significantly than steady-state cardio, thus enhancing cardiovascular fitness and increasing VO2 max, which is the maximum amount of oxygen the body can use during exercise. The alternating intensity levels can also improve metabolic rate, leading to more calories burned both during and after workouts. As a result, interval training is an efficient way to boost endurance and overall fitness levels.