There are approximately 150,000 non-traumatic amputations annually according to the 2021 American Heart Association policy statement: Reducing nontraumatic lower-extremity amputations by 2030: Time to reach our feet. Between 8 and 10 million people in the United States have PAD. The condition disproportionately affects black people, American Indian people, and people of lower socioeconomic status.
This condition occurs when the arteries that carry blood from the heart throughout the body narrow, reducing the flow of blood and oxygen. It usually affects the legs and feet during walking, with symptoms such as cramps, weakness, fatigue, aches and pains or discomfort that subside within 10 minutes of rest.
Previous research found that walking for exercise, especially on a treadmill, while under the supervision of a staff member, improves walking ability and walking distance among people with pads.
The possible effects of walking at a speed that induce symptoms such as leg pain on range of motion, strength and balance remained unclear.
This study examined the effects of home-based walking for exercise among 264 people with PAD who were participating in a randomized clinical trial called the Low-Intensity Exercise Intervention in PAD (LITE). In which a total of 305 people were involved. From September 2015 to December 2019, participants enrolled in the LITE study at four US medical centers (Northwestern University, Tulane University, University of Minnesota, and the University of Pittsburgh). Their median age was 69, 48% were female and 61% were black adults.
Researchers randomly assigned participants to one of three groups for 12 months. The first group (38%) walked at a comfortable pace at home; The second group (41%) walked at home at a pace that prompted leg symptoms; While the third group (21%) did not run for exercise. Both walking exercise groups wore an actigraph, a device that monitored their running intensity and running time.
Individualized thresholds for ActiGraph intensity that corresponded to walking for exercise at a pace inducing leg symptoms (high intensity) and that corresponded to walking for exercise at a comfortable pace without leg symptoms (low intensity) , for each individual randomized to an exercise intervention, was defined. Participants randomized to exercise wore their Actigraph device during walking exercise activity and uploaded data on exercise frequency, intensity and duration to the study website.
At the start of the study and at 6 and 12 months, participants completed three tests of leg function: walking pace over a distance of four meters (13 feet) at a normal pace, speed walking a distance of four meters at the fastest pace. and the Short Physical Performance Battery (SPPB) which includes four meters of walking speed at a normal pace, a standing balance test and five times the chair lift time.
The major findings were:
- in six months, participants whose walking speed induced leg pain or discomfort walked 11 feet per minute faster, and at 12 months, they walked more than 16 feet per minute faster than participants whose walking speed The movement did not cause pain or discomfort in the foot. Compared to non-exercisers, participants in the group exercising with leg pain or discomfort walked about 13 feet per minute faster at six months, however, this increase was not statistically significant at 12 months. .
- in 12 months, people walking for exercise with leg pain or discomfort scored about 1 point higher than those who did not, out of a total of 13 points (0–12), on the Sum of Three Leg Function Test (Short Physical Performance Battery) who walked at a comfortable pace without leg pain. For those who exercised at a comfortable pace, there was no improvement in walking speed at either six months or 12 months, compared with non-exercisers.
“We were surprised by the results because walking for exercise at a speed that causes pain in the legs is known to be associated with damage to the leg muscles among people with PAD,” said senior study author Mary M. McDermott, MD, Jeremiah. Stamler Professor of Medicine in the Division of General Internal Medicine and Geriatric Medicine and Preventive Medicine at Northwestern University’s Feinberg School of Medicine in Chicago. “Based on these results, clinicians should advise patients to walk at a pace for exercise that induces foot discomfort rather than at a pace that is comfortable without pain.”
It underscores the benefits of walking for exercise with the speed that induces pain or discomfort in the foot. “This finding is consistent with “no pain, no gain” with respect to the exercise of walking in a pad,” McDermott said.
“Exercise that induces foot pain is beneficial, although difficult,” McDermott said. “We are now working to identify interventions that can make high-intensity exercise easier and still be beneficial for people with PAD.”
It is important to note that study participants walked at home, so the results may not apply to treadmill running in the presence of a health professional, which is standard of care and first-line therapy in accordance with clinical practice guidelines. In addition, the results of this report were not pre-specified results for this clinical trial. Therefore, these findings should be confirmed in future research.
In May 2022, the American Heart Association and 24 partner organizations launched the PAD National Action Plan, a guide to help prevent PAD complications, treat cardiovascular risk, and improve the quality of life of people living with the disease. .
“PAD is a lifelong medical condition, but people with PAD live active and long lives,” said Joshua Beckman, MD, director of the Vascular Medicine section and professor of medicine at Vanderbilt, American Heart Association volunteer expert and member of the PAD National Action Plan writing group. can.” University in Nashville, Tennessee. “If you notice that walking is becoming more difficult, it is difficult to keep up with others, or you have pain when walking, talk to a doctor and describe when it happens and how it feels.”