An Olympic rower competes in a 2000-metre race lasting approximately 6-7 minutes. Critically analyse how the efficiency of ATP production in different energy systems affects the athlete's pacing strategy and overall performance. (8 marks)
--- 26 WORK AREA LINES (style=lined) ---
Show Answers Only
Sample Answer
Overview Statement
- ATP production efficiency directly influences pacing decisions throughout the 2000m race.
- The relationship between speed and efficiency determines sustainable effort levels at each race stage.
Start Phase and Efficiency Trade-offs
- Initial acceleration relies on ATP-PCr and glycolytic systems for rapid energy despite poor efficiency.
- These systems produce ATP quickly but generate limited amounts per fuel molecule used.
- This inefficiency means the fast start cannot be maintained beyond 30-45 seconds.
- Therefore, rowers must transition to more efficient systems or face rapid exhaustion.
Middle Race Efficiency Optimisation
- The aerobic system provides most ATP during the middle race segments.
- Complete fuel breakdown yields far more ATP per glucose molecule than anaerobic systems.
- This superior efficiency enables sustained high-intensity effort for several minutes.
- Pacing depends on maintaining intensity where aerobic metabolism dominates energy production.
Final Sprint Energy Dynamics
- The last section requires shifting back to less efficient but faster energy systems.
- Glycolytic system reactivation allows increased speed despite efficiency loss.
- Lactic acid accumulation results from this deliberate efficiency sacrifice.
- This trade-off demonstrates how performance goals override efficiency in race-critical moments.
Implications and Synthesis
- Efficiency differences create distinct pacing phases: explosive start, sustained middle, powerful finish.
- The aerobic system’s efficiency determines how fast the middle pace can be maintained.
- Strategic inefficiency at start and finish proves that winning requires more than optimal efficiency.
- Therefore, successful pacing balances the competing demands of speed and sustainable energy production.
Show Worked Solution
Sample Answer
Overview Statement
- ATP production efficiency directly influences pacing decisions throughout the 2000m race.
- The relationship between speed and efficiency determines sustainable effort levels at each race stage.
Start Phase and Efficiency Trade-offs
- Initial acceleration relies on ATP-PCr and glycolytic systems for rapid energy despite poor efficiency.
- These systems produce ATP quickly but generate limited amounts per fuel molecule used.
- This inefficiency means the fast start cannot be maintained beyond 30-45 seconds.
- Therefore, rowers must transition to more efficient systems or face rapid exhaustion.
Middle Race Efficiency Optimisation
- The aerobic system provides most ATP during the middle race segments.
- Complete fuel breakdown yields far more ATP per glucose molecule than anaerobic systems.
- This superior efficiency enables sustained high-intensity effort for several minutes.
- Pacing depends on maintaining intensity where aerobic metabolism dominates energy production.
Final Sprint Energy Dynamics
- The last section requires shifting back to less efficient but faster energy systems.
- Glycolytic system reactivation allows increased speed despite efficiency loss.
- Lactic acid accumulation results from this deliberate efficiency sacrifice.
- This trade-off demonstrates how performance goals override efficiency in race-critical moments.
Implications and Synthesis
- Efficiency differences create distinct pacing phases: explosive start, sustained middle, powerful finish.
- The aerobic system’s efficiency determines how fast the middle pace can be maintained.
- Strategic inefficiency at start and finish proves that winning requires more than optimal efficiency.
- Therefore, successful pacing balances the competing demands of speed and sustainable energy production.