November 15, 2006 (Chicago) — Arm ergometry appears to have some carry-over effect to leg muscles, increasing time to onset of claudication and improving maximal walking distance in patients with peripheral arterial disease (PAD), investigators reported here at the American Heart Association (AHA) 2006 Scientific Sessions.
Principal investigator Diane Treat-Jacobson, PhD, RN, associate professor at the University of Minnesota School of Nursing in Minneapolis, presented a study of 35 patients with "lifestyle-limiting" symptoms of PAD.
Mean age of the subjects was 67 years, 27% had diabetes mellitus, and 87% had a history of smoking.
Patients were randomized to 1 of 3 active treatment groups: arm ergometry using a hand bike, treadmill walking, or a combination of the two. A fourth group assigned to no specific exercise served as control subjects. Exercise sessions were 1 hour in length, 3 times a week for 12 weeks, and were progressive in intensity.
The investigators measured maximal walk distance and time to onset of pain with exercise at baseline and at 12 weeks.
Baseline mean walk distance in the treadmill group increased from 486 to 778 meters, from 441 to 593 meters with arm exercises, from 441 to 663 meters with combination exercise and from 301 to 350 meters in the control group.
Mean distance walked before onset of claudication in the treadmill group increased from 186 to 288 meters, from 144 to 252 meters in the arm ergometry group, from 173 to 235 meters with both arm and leg exercise, and from 109 to 117 meters in the control group.
While symptoms were most improved with treadmill exercise and combination training, the improvement with arm exercise alone was significantly improved over baseline in the arm ergometry patients, Dr. Treat-Jacobson announced.
"It was thought that the improvement in exercise tolerance that occurs with treadmill exercises was a result of local training of leg muscles, but apparently there are systemic effects with exercise," she told Medscape. "It's possible that there is some improvement in endothelial function that affects the entire arterial system."
This was a preliminary study, the investigator cautioned, with the findings limited to exercise and symptom assessment. The investigators plan to assess specific measures of circulation in a larger cohort in upcoming studies.
Dr. Treat-Jacobson reported no relevant financial relationships. The study was funded by the AHA's Greater Midwest Affiliate.
AHA National Spokesperson Elliott Antman, MD, a professor of medicine in Cambridge, Massachusetts, told Medscape that the findings "suggest that training has a global effect."
"It's possible that the heart begins to pump more efficiently, under increased pressure with exercise, such that blood and oxygen reach the legs better. Arm exercise may stimulate growth factors, resulting in a sprouting of new blood vessels in the legs...it may cause the release of substances that would improve endothelial function and it may cause the vessels [in the leg] to dilate, allowing more blood flow to the leg muscles," Dr Antman speculated.
He said the approach could be helpful for the frail elderly and for patients with orthopaedic problems or who are otherwise disabled. "These patients can't really exercise on a treadmill," he said. "For patients who have severe disease, they might be able to get some improvement in symptoms [with an arm exercise program]."
But like Dr. Treat-Jacobson, Dr. Antman cautioned that the findings are preliminary and the actual mechanism by which arm exercise improves walk distance is still unknown.
Dr. Antman had no relevant financial relationships to disclose.
AHA Scientific Sessions 2006: abstract 2760. Presented November 14, 2006.
Medscape Medical News © 2006
Cite this: Martha Kerr. Arm Exercise May Reduce Leg Pain Caused by Peripheral Arterial Disease - Medscape - Nov 15, 2006.