Which statement best describes anaerobic exercise?

• A. Intense, short bursts of energy
• B. Rhythmic activities using large muscle groups for an extended period
• C. Exert resistance with no movement
• D. Combine movement of joints with contractions

Answer: (A)

Anaerobic exercise is characterized by high-intensity effort performed in short bursts. During these efforts the body can’t supply oxygen quickly enough to meet the energy demand, so it relies on stored energy sources like ATP and creatine phosphate and then quickly uses glycolysis to generate more energy. That rapid, powerful work lasts only a short time—usually seconds to a couple of minutes—before fatigue sets in. This is why “intense, short bursts of energy” best describes anaerobic exercise. The other statements refer to different types of activity: sustained rhythmic movements are typical of aerobic endurance; exerting resistance with no movement describes isometric work; and combining joint movement with contractions describes dynamic resistance.