In hyperactive children the arms must first be restrained by holding them tight in our hands. Montessori Elementary Materials Maria Montessori We must stimulate the apathetic and the sluggish; we must moderate the hyperactive; we must correct paresis, tics, etc.
Isotonic contractions are those which cause the muscle to change length as it contracts causing movement. There are two types of isotonic contraction: -. Concentric. A concentric contraction is a type of muscle contraction in which the muscles shorten while generating force.
An isometric contraction of a muscle generates tension without changing length. An example can be found when the muscles of the hand and forearm grip an object; the joints of the hand do not move, but muscles generate sufficient force to prevent the object from being dropped.hough the muscle is doing a negative amount of mechanical work, (work is being done on the muscle), chemical energy (in fat, glucose or ATP) is nevertheless consumed, although less than would be consumed during a concentric contraction of the same force.