Isotonics

Isotonics cause more muscle hypertrophy. It is theorized that this is due to the increased capillarization which is stimulated much more by isotonics than isometrics.

The development of this kind of fitness is brought about only by dynamic movement, by isotonics, usually against fairly moderate resistance, and repeated many times so that the heart and lungs have to work increasingly harder and longer as training progresses.

Hand and wrist isometrics and isotonics are performed in the sling.