An exercise involving muscle contractions with resistance varying at a constant rate is called?

• A. Plyometric
• B. Isokinetic exercise
• C. Isometric exercise
• D. Isotonic exercise

Answer: (B)

Isokinetic exercise involves muscle contractions performed with resistance that varies to keep the movement at a constant speed throughout the range of motion. Special machines adjust the opposing force in real time so that you can exert maximal effort while the joint moves at a preset velocity, whether in concentric or eccentric phases. This is different from isotonic exercise, where the external load is constant but speed can vary; from isometric exercise, where there is no joint movement; and from plyometric exercise, which emphasizes rapid stretching and explosive contractions to build power. So the scenario described—resistance that changes to maintain a constant rate of movement—fits isokinetic training.