| Hypertonia | Excessive muscle tone |
| Hypotonia | Below normal muscle tone |
| Iso | The same |
| Tonic | Holding tone or tension |
| Concentric | Towards the middle (of the muscle) |
| Eccentric | Away from the middle (of the muscle) |
| Kinetic | Moving |
| Isotonic contractions | A muscle contraction in which the tension within the muscle does not change |
| Isotonic Concentric Contraction | A muscle contraction where a muscle shortens as it contracts |
| Isokinetic Contraction | A muscle contraction in which the speed of the movement stays the same |