Comparison of Calf Muscle Blood Flow Responses to Rhythmic Exercise between Mean Age 25- and 74-Year-Old Men 1

Abstract

These studies compared calf muscle strength and calf muscle blood flow response to rhythmic exercise, as gauged by postexercise hyperemia, between a group of young adult males (mean age 24.7 years) and an older group (mean age 73.7 years). All subjects were trained to exert maximum voluntary contractions (MVC) of their calf muscles. MVC values averaged 502 ± 16 (SEM) pounds in the young adult group and 362 ± 53 (SEM) pounds in the older group. This difference was significant (P ± 0.05). Calf muscle blood flow was measured by strain gauge plethysmography before and after 3-min bouts of rhythmic isometric calf muscle exercise. Contraction frequency ranged from 20 to 80 contractions per minute (cpm) while the force per contraction ranged from 7.5 to 30% of MVC. In the resting state there were no significant between-group differences in blood pressure or calf muscle blood flow. For each percentage MVC and cpm exercise combination tested, there were no significant between group differences in postexercise hyperemia. These results indicate that the fundamental relationship between MVC and muscle blood flow is not modified as a function of age.