Abstract
Effects of aging on the force-velocity relation of knee extensors were investigated in 140 healthy males, ages 20 through 72 years. to attain the force-velocity relation, the subjects performed maximal knee extension against each of a given load of some different submaximals by using the weight load system method. The age groups were classified into three groups on the basis of the changes in power with age according to the previous study. After twenties, the maximal leg power decreased with age, in particular on the age group of 60-72 years. From a viewpoint of the component of power output with age was dependent on the greater decrement of leg muscle strength than that of velocity, indicating that the form of force-velocity relations were decreased greatly on the increased loads with elderly age group. On the other hand, it has been reported that a remarkable difference of power output dependent on muscular strength with regard to a comparison between the trained and the untrained, or its trainability greatly causing by the increment of muscular strength. Therefore, considering with these previous findings, it might be suggested that the deterioration of muscle strength affects directly on power output with the age group of 60-72 years. Morphologically it may be a decrease of muscular mass in leg extensors.
