Comparison of treadmill walking and stair climbing over a range of exercise intensities in peripheral vascular occlusive disease.

Although claudication pain and hemodynamic responses to exercise are related to the degree of arterial narrowing in the lower extremities, the nature of these responses to different exercise tasks and intensities is less clear. Thus, the purpose of this study was to compare claudication and hemodynamic responses to graded walking, level walking, and stair climbing over a range of exercise intensities. Ten patients with peripheral vascular occlusive disease performed five tests within each of the three exercise tasks. Similar values of oxygen consumption were obtained among exercise tasks at each intensity (p = ns). Time to onset of claudication pain and to maximal pain were similar among exercise tasks (p = ns), and both demonstrated a curvilinear decrease as intensity increased (p < 0.05). Foot transcutaneous oxygen tension, ankle systolic blood pressure, and ankle/brachial systolic pressure index were also similar among the three exercise tasks (p = ns); however, each decreased linearly as exercise intensity increased (p < 0.05). Thus, in peripheral vascular occlusive disease, the imbalance between oxygen delivery to the exercising lower extremity musculature and the local metabolic demand is similar during different weight-bearing activities. Second, even though the peripheral circulation is progressively impaired with increased exercise intensity, anaerobic metabolism in the ischemic lower extremity musculature may prevent a continual decline in claudication times. The clinical implication is that a more thorough assessment of the functional limitations imposed by claudication pain is not obtained by using different types of weight-bearing exercise tests as opposed to using on ly one type.