- Isometric contraction is the contraction of the muscle without change in muscle length.
- The tension increases during contraction.
Q.1 What are the differences between isometric and isotonic contractions?
Isometric contraction
- Here the muscle contracts and the length of the muscle remains the same, so no external work is done
- It is used to improve tone and strength of the muscle
Isotonic contraction
- Here length of the muscle changes while tension remains the same, therefore external work is done
- It is used to strengthen muscle and its tone and improve joint mobility
Q.2 Give an example of isometric contraction of muscles in humans.
Examples of Isometric contraction
- Muscle which helps maintain posture against gravity
- Muscle contraction while trying to push a wall
Examples of Isotonic contraction
- When the legs are moving while walking and running
- Contraction of arm muscle while lifting a load