Peripheral arterial insufficiency, effect of physical training on walking tolerance, calf blood flow, and blood flow resistance.

Twenty-three patients with intermittent claudication were submitted to physical training during 4-6 months. Eleven other patients with intermittent claudication served as a control group and were given placebo tablets during the same period. The aim of the investigation was to study the influence of physical training on the blood flow conditions in the calf. The effect of treatment on walking tolerance, on calf blood flow, blood flow resistance, and systolic blood pressure graident between the systemic circulation and the vascular bed in the calf was studied. Half a year after the end of the treatment period the patients were reexamined. The walking tolerance increased in both groups but more in the trained group. The increase in walking tolerance even in the control group was caused by the fact that the control group began to train to some extent. In neither group the maximal calf blood flow changed significantly compared with the pretreatment values. The maximal blood flow showed an increasing trend in the training group after a period fo 4 months compared with the control goupr (2p greater than 0.10). The blood flow resistance at maximal dilatation did not change significantly as compared with the initial values in any of the groups, but there was a significant difference (2p greater than 0.05) between the two groups with a decrease in the training group after 4 months. The changes in maximal calf blood flow and the changes in blood flow resistance at maximal dilatation were not related to the changes in walking tolerance. Half a year after the treatment period the walking tolerance had not decreased and there was no difference between the two groups. The maximal calf blood flow, the blood flow resistance, and the systolic pressure gradient were unchanged in comparison with the pretreatment values and there were no statistically significant differences between the two groups. The small changes in blood flow conditions observed after physical training cannot be the only factor explaining the well known improvement in walking tolerance. However, training may cause a redistribution of the blood flow in the working muscle.