A unique exercise known as Nordic walking may be more beneficial for coronary heart disease patients than standard moderate and high-intensity exercise regimes.
Coronary artery disease is a condition where the arteries that supply the heart with blood become clogged by a build-up of fatty “plaque”. This can lead to chest pains, blood clots and heart attacks. According to the Heart Foundation, an average of two people died of coronary artery disease every hour in Australia in 2018.
As part of their medical treatment, patients with coronary artery disease are often encouraged to take up exercise programs to improve their fitness, mental health, and ability to participate in daily life activities – also known as functional capacity.
The results of a new randomised clinical trial, published in the Canadian Journal of Cardiology, compared improvements in functional capacity, quality of life, and depression symptoms among 130 patients with coronary artery disease who were randomly assigned to different exercise programs. The patients completed 12 weeks of either high-intensity interval training, moderate to vigorous-intensity continuous exercise training, or Nordic walking, followed by 14 weeks of observation.
What is Nordic walking?
Nordic walking is a type of walking exercise that originated in Finland as a summer training exercise for cross-country skiers. Nordic walkers use special poles to engage muscles in the upper body as well as in the legs when walking. This is part of the reason why the research team chose to study Nordic walking over some other exercises typically prescribed for cardiac rehabilitation, such as walking and cycling, which primarily use the lower body.
“The use of poles reduces loading stress at the knees, and the recruitment of core and upper body muscles increases energy expenditure,” explains first author Tasuku Terada, of the University of Ottawa Heart Institute, Canada. “We were interested in understanding the effects of whole-body aerobic exercise.”
What did the study find?
Patients in all three programs experienced mental and physical benefits from their new exercise regimes. However, the Nordic walking group showed the greatest improvement in their functional capacity – based on the distance they were able to walk in six minutes – with an improvement of 19% compared to 13% for high-intensity interval training and 12% for moderate to vigorous-intensity continuous training.
“This is a key finding, because lower functional capacity predicts higher risk of future cardiovascular events in people with coronary artery disease,” says lead investigator Jennifer L. Reed, also of the University of Ottawa Heart Institute.
Erin Howden, head of the Human Integrative Physiology Lab at the Baker Heart and Diabetes Institute in Melbourne, who was not involved in the study, agrees that the Canadian research offers encouraging news for patients.
“If you can do exercise that you enjoy, you are going to get benefit, but if you do exercise that is more intense or more whole-body, then you can get even greater benefit from participating in structured exercise,” she says.
Bringing broader benefits
However, some challenges still remain. Howden points out that only a small number of the over 1,000 patients initially assessed for eligibility to join the study ended up participating.
“Many of the people who were assessed for eligibility didn’t participate because of ‘other’ reasons, like they didn’t live close enough to the centre, or there were issues with attending the class time,” she says. “We need to be able to tap into offering those people interventions as well, to try and broaden the effectiveness of our exercise programs.”
“The big picture is we want people who have had a cardiac event to safely and sustainably increase their physical activity levels, then keep it that way,” says Andrew Reynolds, a senior research fellow in health sciences at Otago University, New Zealand, who was also not involved in the new study. “How they can do that can be in a way that interests them.
“I’d choose the walking over the gym-based stuff, just because you can be outside,” Reynolds adds. “Interaction with green space also affects quality of life and depressive symptoms in some of the previous research.”
The University of Ottawa researchers hope to continue investigating the benefits of Nordic walking in combination with high-intensity interval training for coronary artery disease. According to Terada, further studies are also needed to understand whether Nordic walking has comparable benefits for patients with other heart conditions.