Mon Prof Augmenté
Muscle acid and fatigue
Age 16 · Health
Hard exercise can make muscles acidic as hydrogen ions build up. Oxygen helps combine these ions into water, but when oxygen is insufficient, lactate accumulates and muscles tire.
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Age 16: open this week
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In the picture
- A muscle fibre: the working cell that releases hydrogen ions during hard exercise.
- A hydrogen ion: an acidic particle that builds up in the muscle fibre.
- An oxygen molecule: a particle delivered by a red blood cell.
- A water droplet: what forms when oxygen joins hydrogen ions.
- A lactate crystal: a substance that accumulates when oxygen is insufficient and tires muscles.
Examples
- Sprinting uphill.
- Doing heavy squats.
Key takeaways
- Oxygen joins hydrogen ions into water, reducing acidity.
- Insufficient oxygen lets lactate build up and tires muscles.
Quiz: Muscle acid and fatigue (Age 16)
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During hard exercise, what do oxygen molecules combine with hydrogen ions to form?
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Why does lactate build up in a muscle during hard exercise?
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What effect does accumulated lactate have on muscles?
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