Elite swimmers can complete a 200 metres free-style race in just under 2 minutes. Describe how the majority of energy will be produced for this type of race.

Elite swimmers can complete a 200 metres free-style race in just under 2 minutes. Describe how the majority of energy will be produced for this type of race.

• A. Primarily anaerobic energy production via glycolysis
• B. Predominantly aerobic metabolism
• C. Fat oxidation dominates
• D. Phosphocreatine supplies most energy

Answer: (A)

The race demands a high rate of ATP production for roughly 2 minutes, so the body relies on anaerobic glycolysis as the main energy source. The phosphocreatine system provides immediate energy at the start, but its stores are only enough for a few seconds, so they’re exhausted early. Anaerobic glycolysis then takes over to generate ATP quickly without oxygen, which also produces lactate as a byproduct. While the aerobic system is active and contributes, its rate of ATP production is slower than glycolysis and cannot meet the rapid energy demands for most of the race. Fat oxidation is too slow to supply the needed ATP at this intensity. Therefore, the majority of energy comes from anaerobic glycolysis.

The race demands a high rate of ATP production for roughly 2 minutes, so the body relies on anaerobic glycolysis as the main energy source. The phosphocreatine system provides immediate energy at the start, but its stores are only enough for a few seconds, so they’re exhausted early. Anaerobic glycolysis then takes over to generate ATP quickly without oxygen, which also produces lactate as a byproduct. While the aerobic system is active and contributes, its rate of ATP production is slower than glycolysis and cannot meet the rapid energy demands for most of the race. Fat oxidation is too slow to supply the needed ATP at this intensity. Therefore, the majority of energy comes from anaerobic glycolysis.