Abstract
Manner of muscular relaxation in elbow flexion was observed on the subjects aged from 7 to 22 years old. Relation between surface electromyogram of m, biceps brachii and mechanogram of elbow flexion were used for the parameters of muscular relaxation.
Results were as follows: 1) At elder subjects, silence of surface electromyogram preceeded to the tension decrease. But discharge of surface electromyogram preceeded during muscular relaxation at younger subjects. 2) It could be observed the transient tension increase before muscular relaxation. The appearance rate of the transient tension increment increased as becoming elder.
From above results, it could be considered that the inhibitibility of spinal alpha motoneuron pool did not yet developed for about 7 years old.
