Speed and age: multiple rates of age decline.

There is frequent reference in the literature on aging and performance to the "slowing with age phenomenon". If there truly is one "slowing with age" phenomenon, then all activities requiring speeded performance should decline with age at approximately the same rate. This report compares relative rates of age decline in several speeded physical activities ranging from simple reaction time to long distance running events. The activities differ in the rate of slowing with those requiring a greater muscular involvement or more stamina exhibiting the steepest declines. It is concluded that when one refers to slowing with age it is necessary to be quite specific about the activity to which one is referring because different activities decline at different rates.