Blood flow changes following brief concentric contractions of human calf muscles

The present study was designed to clarify the venous return, filling velocity (Maximum Inflow Rate: MIR), and post-contraction hyperemia following brief concentric contractions of human calf muscles, using a double-stranded mercury-in-silastic gauge. The subject, in a prone position, extended the right ankle joint to 5, 10, 15, and 20 degrees at 20 degrees.sec-1 with a load of 20% of maximum voluntary contraction in ankle extensors. There was a significant relation between increase in calf girth at contraction and the amount of decrease, increase, total change (decrease plus increase), and MIR in calf volume after relaxation, and also between the MIR and amount of decrease, increase and total change in calf volume. The amplitude of the volume pulse wave apparently increased immediately after muscle relaxation, then progressively decreased. The maximum value appeared with the greatest increase in ankle extension. It was found that with increased muscle contraction, there was accelerated venous return, filling velocity of blood, and post-contraction hyperemia. Pulsatile blood flow into muscle tissue after brief muscle contractions might be qualitatively measured by the amplitude of the volume pulse wave.