Size principle
What Size principle means in Physical Education A-Level, as defined for AQA.
Definitions of Size principle
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Reference: AQA
Small units containing slow-twitch fibres and generating little force are activated first, with larger units with fast-twitch fibres added as force demand rises.
Smaller motor units are recruited before larger ones as the required force rises.
Topics that use Size principle
- Neuromuscular system (AQA A-Level)
Related terms
- Aerobic and anaerobic ATP resynthesis
- Aerobic ATP resynthesis
- Aerobic oxidation
- All-or-none law
- Calcium ion retention
- Calcium ions
- Endurance activity performance
- Fast glycolytic (type IIx)
Using Size principle in the exam
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