In the randomized, controlled six-month clinical experiment, the results of which were published in the Journal of the American Medical Association, 156 patients were divided into three groups by Mary M. McDermott, of the Northwestern University Feinberg School of Medicine, in Chicago, and her colleagues.
One group engaged in supervised treadmill exercise, and another in lower-leg resistance (strength) training over the course of the six months. The third was the control group. During the study, patients were tested in six different ways. One test, for example, measured their performance in a six-minute walk. After six months, those in the treadmill exercise group were able to walk an average of 69 feet farther than what they had at the beginning.
By contrast, members of the control group walked an average of 49 feet less than they had at the start. Patients in the resistance training group were able to go 41 feet farther compared with the control group. Another test measured the ability of the brachial artery, an artery in the arm, to dilate, an indication of arterial suppleness and health.
The treadmill exercisers improved in their artery dilation, while the resistance trainers and control group did not. The 156 patients also filled out two questionnaires that gauged the level of their physical functioning and walking impairment. On both of these, the treadmill exercise group improved significantly more than the control group over the course of the study.
The resistance trainers improved somewhat over the control group, but not as much as the treadmillers. "Based on findings reported in this trial, physicians should recommend supervised treadmill exercise programs for PAD patients, regardless of whether they have classic symptoms of intermittent claudication [leg pain]," the authors conclude.