OBJECTIVE: To assess the acute metabolic and cardiovascular responses to walking exercise at an intensity corresponding to the heart rate of claudication pain onset and to investigate the effects of a 12-week walking training program at this intensity on walking capacity.
METHODS: Twenty-nine patients with intermittent claudication were randomly allocated to the walking training (n=17) or control (CO, n=12) group. The walking training group performed an acute exercise session comprising 15×2-min bouts of walking at the heart rate of claudication pain onset, with 2-min interpolated rest intervals. The claudication symptoms and cardiovascular and metabolic responses were evaluated. Walking training was then performed at the same intensity twice each week for 12 weeks, while the control group engaged in twice weekly stretching classes. The claudication onset distance and total walking distance were evaluated before and after the interventions. Brazilian Registry Clinical Trials: RBR-7M3D8W.
RESULTS: During the acute exercise session, the heart rate was maintained within tight limits. The exercise intensity was above the anaerobic threshold and >80% of the heart rate peak and VO2peak. After the exercise training period, the walking exercise group (n=13) showed increased claudication onset distance (309±153 vs. 413±201m) and total walking distance (784±182 vs. 1,100±236m) compared to the control group (n=12) (p<0.05).
CONCLUSION: Walking exercise prescribed at the heart rate of claudication pain onset enables patients with intermittent claudication to exercise with tolerable levels of pain and improves walking performance.