University of Minnesota researchers have led efforts nationally to prove that supervised exercise is as effective as stents or bypass surgeries — and cheaper — for people with narrowed arteries and inadequate blood flow to their legs.

Now their approach appears likely to receive the ultimate seal of approval: a decision by the federal Medicare program to cover it for elderly Americans.

“This means that, wherever you lie in the United States, it's very likely you will soon have access to the treatment,” said Dr. Alan Hirsch, a U researcher who petitioned for Medicare coverage after years of research on the use of exercise therapy to relieve pain and other symptoms of peripheral artery disease, or PAD.

A stigma holding back PAD therapy in the past was the fact that it involved walking exercises that traditionally haven’t been covered by an American medical system that is used to paying for drugs and surgeries. But recent studies have shown that patients doing exercises gained more function than those who received costly stents alone to prop open narrowed arteries.

Critics might think that patients should exercise on their own, without insurance coverage or medical help, but they often quit without support due to the recurring pain, said Diane Treat-Jacobson, a U nursing professor who has studied PAD treatment.

“The fact of the matter is, it hurts,” she said. “We’re asking patients to walk into pain, rest, walk into pain, rest, and keep doing it for an hour at least three days per week.”

What U researchers found over time is that continued exercise allows people to work out pain-free for longer periods and feel better in their daily lives.

Finding low-cost solutions is critical, because PAD afflicts an estimated 120 million people worldwide and is associated with smoking, diabetes and simply aging, Treat-Jacobson said. “We can’t do much about the third one, and there are a whole lot of people who are doing it.”

The Twin Cities is one of the only metro areas with eight structured PAD exercise programs, where patients pay around $150 out of pocket for three months, Hirsch said.

Treat-Jacobson has led the use of a $1.6 million grant to help doctors in four rural communities — Fergus Falls, Morris, Glenwood and Elbow Lake — detect PAD and offer structured exercise treatment. (PAD is largely diagnosed by comparing differences in blood pressure readings taken at the arm and ankle.)

She also has tested whether pain-free arm exercises increase circulation and produce the same benefits as walking.

Medicare has proposed covering 36 exercise workouts over 12 weeks, and 36 more sessions if doctors document that they are needed. A final decision is expected this spring.

“Supervised exercise therapy does improve function,” Hirsch said. “It also probably improves blood pressure, diabetes, self confidence and quality of life with almost no demonstrated risk and an unbelievably lower cost than placing metal in arteries, which has been the standard of medicine in the U.S. for 30 years.”