Which energy system uses glucose and lasts up to 2-3 minutes?

• A. ATP-PC
• B. glycolysis
• C. anaerobic
• D. aerobic

Answer: (B)

This question tests how fuel source and duration align with energy systems. The energy system that uses glucose and provides rapid ATP for short, high-intensity efforts—typically dominating for about 1 to 2 minutes, sometimes up to 2–3 minutes—is glycolysis. In glycolysis, glucose is broken down to pyruvate, yielding ATP quickly. If oxygen is limited, pyruvate is converted to lactate, allowing continued ATP production in the anaerobic pathway. When oxygen is available, glycolysis can still feed into the aerobic system for longer work, but the key point for this timeframe is that glycolysis is the glucose-using, fast-energy pathway that covers roughly the first couple of minutes of intense activity. The ATP-PC system doesn’t use glucose and lasts only about 10 seconds, while the aerobic system uses glucose but requires oxygen and sustains energy well beyond a few minutes.