Which energy system is dominant in the 100m sprint?

• A. Glycolytic system.
• B. Oxidative system.
• C. Lactic acid system.
• D. Adenosine triphosphate-phosphocreatine (ATP-PC) system.

Answer: (D)

The energy demand of a 100 m sprint is met most quickly by the ATP-PC system, which provides immediate ATP without the need for oxygen. Muscle stores of phosphocreatine donate a phosphate to ADP to rapidly regenerate ATP, delivering energy at a very high rate to fuel the fast start and early acceleration. These phosphocreatine stores are limited, so this system dominates mainly in the initial seconds of maximal effort. As time goes on and phosphocreatine is depleted, energy production shifts more toward anaerobic glycolysis and, to a lesser extent in this short race, the oxidative system remains minimal because there isn’t enough time or oxygen delivery for it to contribute substantially. That's why the ATP-PC system is the best answer for the dominant energy source in the 100 m sprint.