250919 Strength training properties part 3 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.
Have you considered the influence the CNS has on the body during one limb lifts? It has been shown that greater force production occurs while exercising one limb at a time than when both are used simultaneously. Reasons vary for this phenomenon but include by exercising unilaterally the neural activity is more concentrated on the one limb. Another theory is by exercising one limb at time the other limbs motor units are not interfering by participating in the movement. The result of having more strength and power with one limb compared to using and combining the total of both limbs is a bilateral deficit. Bilateral deficit, if displayed by the athlete, occurs in both arms and both legs not in one leg and one arm.
Now in my experience this is a rare occasion, one in fact that I have never observed in the athletes that train with me. Most have difficulty even approaching half the total of two limbs with one limb. A classic example is the military press. How many can military press two hundred pounds with one arm? A few, granted, but not many. Most however can military press two hundred pounds with two arms.
Now the literature bears this observation out as the bilateral deficit generally occurs only in untrained individuals. Most weightlifters lift bilaterally with either the arms or both of the legs moving in the same direction and not separately.
This is known as bilateral facilitation, which is obviously the reverse of bilateral deficit.