Mon Prof Augmenté
Fast and Slow Muscle Fibres
Age 12 · Biology
Muscles are made of different kinds of fibres. Fast fibres work for quick bursts, while slow fibres keep going for a long time without tiring as quickly.
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In the picture
- A thick deep-red fibre in the sprinter’s thigh: built for rapid, powerful contraction.
- A thin pale fibre in the sprinter’s thigh: built for steady, low-energy work.
- A thick deep-red fibre in the distance runner’s thigh: built for rapid, powerful contraction.
- A thin pale fibre in the distance runner’s thigh: built for steady, low-energy work.
Examples
- Sprinting to catch a bus uses fast fibres.
- Jogging for a long time uses slow fibres.
Key takeaways
- Fast fibres contract quickly but tire fast.
- Slow fibres use less energy and support endurance.
Quiz: Fast and Slow Muscle Fibres (Age 12)
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What do fast muscle fibres do?
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What do slow muscle fibres help with?
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What is the main difference between fast and slow muscle fibres?
The answers, each with its explanation, are in the app. This lesson has left the free week, so its quiz is part of the subscription.
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