Explain how carbohydrate loading can improve performance for a marathon runner. (4 marks)
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Sample Answer
- Carbohydrate loading involves substantially increasing carbohydrate intake over 2-4 days while tapering training. This leads to maximised muscle glycogen stores.
- Because glycogen is the primary fuel for the aerobic energy system, this enables marathon runners to maintain energy throughout events lasting over 90 minutes.
- The increased glycogen storage results in delayed onset of fatigue. This occurs because runners have more fuel available before depletion begins.
- Therefore, carbohydrate loading prevents the performance decline known as “hitting the wall” which happens when glycogen stores become exhausted.
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Sample Answer
- Carbohydrate loading involves substantially increasing carbohydrate intake over 2-4 days while tapering training. This leads to maximised muscle glycogen stores.
- Because glycogen is the primary fuel for the aerobic energy system, this enables marathon runners to maintain energy throughout events lasting over 90 minutes.
- The increased glycogen storage results in delayed onset of fatigue. This occurs because runners have more fuel available before depletion begins.
- Therefore, carbohydrate loading prevents the performance decline known as “hitting the wall” which happens when glycogen stores become exhausted.