'All or none' law, motor units, recruitment and impulse frequency

What this note covers

1. The 'all or none' law
2. Motor unit size and its effect on force control
3. Fibre recruitment: adding motor units to increase force
4. Frequency of impulse: the second way force is graded
5. Worked example: grading force during a gradual lift
6. Common wording errors in marking keys for this content
7. How this content is examined and what separates a top response

7 sections · 10 key terms & formulas · 6 common mistakes