Which outcome is a direct benefit of anaerobic exercise described in the material?

• A. Builds lean muscle
• B. Improves flexibility
• C. Increases long-distance endurance
• D. Reduces bone density

Answer: (A)

Anaerobic exercise involves short, high-intensity efforts that rely on stored energy in the muscles. This type of work stimulates muscle fibers to grow bigger and stronger, leading to increased lean muscle mass. That direct buildup of muscle mass is the primary adaptation you’d expect from these bursts of power and sprint-like activity. Flexibility comes from stretching and mobility work, not from short, intense exertion. Long-distance endurance develops mainly through aerobic energy systems and sustained, lower-intensity activity, while bone density tends to improve with resistance and impact training rather than decrease. So the direct, most consistent outcome described is the increase in lean muscle.