Exercise has many well-established heart benefits, including lower blood pressure and a reduced risk of obesity and type 2 diabetes. For heart disease patients, regular exercise can also help improve blood flow, prevent heart attacks, and promote what’s known as cardiorespiratory fitness — or how easily the circulatory system supplies muscles with oxygen. What’s less clear, however, is the exact type of exercise that can best help heart disease patients improve their functional mobility so it’s easier for them to navigate daily life.
How the Study Was Conducted
For a recent study, researchers set out to answer this question by testing out how fast people moved and how easily they managed daily routines with three common types of workouts: high-intensity interval training (HIIT), or moderate- to vigorous-intensity walking at a continuous pace with or without the addition of Nordic walking poles. They randomly assigned 130 patients with heart disease to do one of these three workouts for 12 weeks, then followed them for an additional 14 weeks to see which group did best in terms of mental health, quality of life, and functional capacity assessed by how far they could go in a timed six-minute walking test. Over the entire 26-week study period, functional capacity based on the distance covered in six-minute walking tests improved in all three groups. But gains were significantly better with Nordic walking than with HIIT or the other walking group, researchers reported June 14 in the Canadian Journal of Cardiology. At the final assessment, participants in the Nordic walking group went an average of 695 meters in six minutes, a 19 percent improvement from where they started out. By comparison, the HIIT group walked an average of 645 meters, a 13 percent improvement, and the other walking group went an average of 628 meters, a 12 percent improvement. “This is a key finding, because lower functional capacity predicts higher risk of future cardiovascular events in people with coronary artery disease,” says Jennifer Reed, PhD, the senior study author and the director of the exercise physiology and cardiovascular health lab at the University of Ottawa Heart Institute in Ontario. “Patients with coronary artery disease frequently demonstrate diminished functional capacity, low quality of life and increased the risk of subsequent cardiovascular events and mortality,” Dr. Reed adds. One limitation of the study is that it followed people for only a few months, making it unclear whether the relative benefits of Nordic walking would hold up over time. Another drawback of the study is that it relied on timed walking tests as a marker for functional abilities, rather than assessing how easily people could complete common daily activities like dressing, bathing, or going out for groceries. The study also wasn’t designed to determine why Nordic walking might have advantages over HIIT or moderate- to vigorous-intensity continuous exercise. “Nordic walking engages core, upper, and lower body muscles while reducing loading stress at the knee, which may have resulted in greater improvements in functional capacity,” Reed says.
What Is Nordic Walking?
Nordic walking is a whole-body workout a lot like cross-country skiing, minus the snow and skis, according to Harvard Medical School. It’s more intense than walking at a continuous pace because it requires people to use major muscles in their shoulders, core, arms, and legs. One advantage to Nordic walking is that it’s accessible even for people who have balance problems because they can use the poles for increased stability and support, according to Harvard. “This form of exercise is ‘whole-body’ because it engages the legs and the arms, and as result, there’s a higher level of energy expenditure than with regular brisk walking,” says Peter Katzmarzyk, PhD, an associate executive director of population and public health sciences at Pennington Biomedical Research Center in Baton Rouge, Louisiana. “This could be one reason why this group had better results for increases in functional capacity,” says Dr. Katzmarzyk, who wasn’t involved in the new study. The study results suggest that Nordic walking might be one way to help people who are bored with continuous training like traditional walking try something more challenging and interesting, wrote Carl Lavie, MD, the medical director of cardiac rehabilitation and prevention at the John Ochsner Heart and Vascular Institute in New Orleans, and colleagues in an editorial accompanying the new study. Nordic walking offers a way to step up the workout intensity without going all the way to HIIT workouts that may be too hard for some heart patients to complete, the editorial notes. HIIT workouts typically involves bouts of intense effort followed by recovery periods of minimal effort. More research should assess Nordic walking with methods that are better at testing heart benefits than the six-minute walking test, Dr. Lavie says. Researchers could get a more complete picture of the benefits with a cardiopulmonary stress test to see how well the heart and lungs work during exercise, or a traditional treadmill test that keeps increasing the speed and incline until people can’t continue, he suggests. Exercise scientists often recommend HIIT as the best workout for people to try if their goal is to achieve maximum fitness benefits, Lavie notes. But not all heart disease patients can handle HIIT workouts. “The addition of Nordic poles with moderate- to vigorous-intensity walking is a simple, accessible option to enhance improvements in walking capacity, increase energy expenditure, engage upper body musculature, and improve other functional parameters such as posture, gait, and balance,” Lavie says. “All that could improve walking speed.”
