Both methods are used to objectively measure the force of specific muscle groups. In the isometric force measurement, the test person presses against a fixed lever arm in a pre-determined joint position with maximum tension. The force applied is recorded by sensors and displayed graphically by an evaluation software.
In the isokinetic measurement, the lever arm moves at a predefined speed while the test person is working with the same force in the same direction – almost trying to push the lever faster. Thus, it’s possible to analyse in which joint position how much force could be applied.