Analyse how the three energy systems interact to provide energy during a 1500 metre race. (8 marks)
--- 22 WORK AREA LINES (style=lined) ---
Show Answers Only
Sample Answer
- As the race begins, the ATP-PCr system provides immediate energy for the explosive start and initial acceleration to race pace within the first 10 seconds.
- The lactic acid system then becomes increasingly important during the first 400 metres as runners establish position and settle into race pace, contributing approximately 15% of energy requirements.
- The aerobic system becomes the dominant energy provider after the first lap, delivering approximately 85% of energy needs for the remainder of the race through oxidative phosphorylation.
- During tactical surges or when overtaking competitors, there is increased contribution from the lactic acid system while the aerobic system continues to operate.
- Brief reductions in pace allow partial replenishment of ATP-PCr stores which can then be utilised for short bursts of acceleration when responding to competitors’ moves.
- Accumulated lactic acid from anaerobic glycolysis may begin to impact performance in the final stages of the race if the pace has been too aggressive.
- The aerobic system’s efficiency in providing energy while clearing metabolic waste products becomes crucial in maintaining race pace through the middle stages.
- Throughout the race, all three energy systems operate simultaneously with their relative contributions shifting based on pace changes and tactical demands of the race.
Show Worked Solution
Sample Answer
- As the race begins, the ATP-PCr system provides immediate energy for the explosive start and initial acceleration to race pace within the first 10 seconds.
- The lactic acid system then becomes increasingly important during the first 400 metres as runners establish position and settle into race pace, contributing approximately 15% of energy requirements.
- The aerobic system becomes the dominant energy provider after the first lap, delivering approximately 85% of energy needs for the remainder of the race through oxidative phosphorylation.
- During tactical surges or when overtaking competitors, there is increased contribution from the lactic acid system while the aerobic system continues to operate.
- Brief reductions in pace allow partial replenishment of ATP-PCr stores which can then be utilised for short bursts of acceleration when responding to competitors’ moves.
- Accumulated lactic acid from anaerobic glycolysis may begin to impact performance in the final stages of the race if the pace has been too aggressive.
- The aerobic system’s efficiency in providing energy while clearing metabolic waste products becomes crucial in maintaining race pace through the middle stages.
- Throughout the race, all three energy systems operate simultaneously with their relative contributions shifting based on pace changes and tactical demands of the race.