200919 Strength training properties part 1 of 3
Morphological changes naturally occur in those who strength train. These changes in the muscle composition result from increases in the amount of muscle glycogen, the number of mitochondria, the capillaries, the muscle fiber size, the tissues of the connective structures, and even the bones of the affected muscles become stronger by increasing their density.
Additional changes taking place in the nervous system include improvements in the intermuscular and intramuscular coordination of the muscles. The main changes are believed to occur in the recruitment and synchronization of the motor units. Training with and subsequently overcoming maximal resistance “causes recruitment of a maximal number of motor units-nerve cells and muscle cells innervated by them and the synchronization of their activity”. (Zatsiorsky 1995)
It should be noted that these morphological and functional changes are specific for each different exercise.
For example use of isometric exercises for an extended time will result in an increase of muscle cell sarcoplasm, nuclei that is rounded in shape, transverse expansion of the motor plates, non symmetric capillary structure (illogical paths of capillary construction which seems to serve no specific purpose) and finally a thickening of the single muscle cell and muscle bundle materials (endomisium and perimisium), extensions of the motor plates along the muscle cell length and a very pronounced transverse striations in the myofibrils which are the contractile portions of the muscle cells-these are the ones that make our muscles do work for us. (Bondachuk et al 1984)
There is very little transfer of strength between the different movement types, i.e. isometric, concentric and eccentric even in the same muscles of the sport. Even a little transfer may benefit the strength athlete thus all positive development are encouraged. Keep in mind the specificity of training principles, which have direct application to the strength and power sports.