V.1. The concept of strength

It is a psycho-physical ability that defines performance and created by muscle tension enabling to overcome relatively high resistance. The force is produced by the muscles which create movement and win over resistance with the help of the joints and system of bones.

In the thickening of the muscles the period of tension plays a crucial role while the measure of tension depends on the number of stimulated motor units and relates to the magnitude of force exerted. (Harsanyi, 2001)