By Pat Anson, PNN Editor

“No pain, no gain” is a phrase that caught on in the 1980’s when fitness videos promoting aerobic exercise became popular. Most doctors today will say that’s bad advice, because physical pain during exercise could be a sign of a serious injury or health problem. Pain is your body’s way of warning you that something is wrong.  

But it turns out that pain and discomfort while walking for exercise may actually be a good thing for people with peripheral artery disease – PAD for short – a condition that occurs when arteries become narrow or clogged, reducing the flow of blood and oxygen throughout the body.

In a new study published in the Journal of the American Heart Association, researchers reported that people with PAD who experienced cramping, soreness, fatigue and other ischemic leg symptoms while walking may actually benefit from the pain.

“We were surprised by the results because walking for exercise at a pace that induces pain in the legs among people with PAD has been thought to be associated with damage to leg muscles,” said senior author Mary McDermott, MD, an Internal Medicine and Geriatric Professor at Northwestern University’s Feinberg School of Medicine. “Based on these results, clinicians should advise patients to walk for exercise at a pace that induces leg discomfort, instead of at a comfortable pace without pain.”

McDermott and her colleagues followed 264 mostly elderly people with PAD for 12 months, randomly assigning them to one of three groups. The first group walked at home at a comfortable pace; the second group walked at a faster pace that induced ischemic leg symptoms; and the third group did not walk for exercise.

Participants who walked were asked to exercise 5 days per week for up to 50 minutes, while wearing an ActiGraph, a device that monitored the intensity and duration of their walking.

After six months, researchers found that people who walked at a pace that induced ischemic leg symptoms walked significantly faster in daily life than those who did not exercise or walked at a comfortable pace without leg symptoms. They also performed better on a physical performance test that assessed their speed, strength and balance. The findings were similar after 12 months.

“This finding is consistent with ‘no pain, no gain’ with regard to walking exercise in PAD,” McDermott said in a press release. “Exercise that induces leg pain is beneficial, though difficult.

“We now are working to identify interventions that can make the higher intensity exercise easier -- and still beneficial -- for people with PAD.”

Between 8 and 10 million people in the United States have PAD. The condition disproportionately affects African-Americans, Native Americans and those with low socioeconomic status.

Previous research found that walking for exercise improves walking ability and walking distance for people with PAD. What remained unclear, until now, were the potential effects of walking at a pace that induced symptoms such as leg pain.

The American Heart Association and 24 other organizations recently launched the PAD National Action Plan, a guide to assist in the prevention of PAD complications, reduce cardiovascular risk, and improve quality of life for those living with the disease.

“PAD is a lifelong medical condition, but people with PAD can lead active and long lives,” said Joshua Beckman, MD, professor of medicine at Vanderbilt University. “If you notice walking is becoming more difficult, keeping up with others is hard, or you have pain when you walk, talk with a doctor and describe when it happens and how it feels.” 

A recent study found that walking for exercise is also beneficial for people with osteoarthritis, who experienced 40% less knee pain than non-walkers.