When it comes to walking for health, longer is better, study suggests

Extending the length of your daily walks may benefit your heart, new research suggests.

In a study of healthy adults, people who took most of their daily steps in bursts of 15 minutes or more had significantly lower risks of heart disease and death nearly a decade later than those who took several shorter walks throughout the day. The study was published Monday in the journal Annals of Internal Medicine.

Additionally, adults who had been less active in the past and took longer walks experienced the greatest health gains.

An international team of scientists examined the daily movements of 33,560 adults with an average age of 62 living in the United Kingdom, using information collected from 2013 to 2015 in a medical research database called UK Biobank. For three to seven days, participants wore an accelerometer on their wrist that recorded their physical activity.

The researchers divided people into four groups, based on how they logged most of their steps each day: in periods of less than five minutes, five to less than 10 minutes, 10 to less than 15 minutes, and 15 minutes or more. The largest group – 42.9% of participants – fell into the less than five minutes category.

After about 9 1/2 years of follow-up, the researchers found that people who walked in spurts of 15 minutes or more had the lowest risk of dying during the study period, while people who walked less than five minutes had the highest risk.

People who walked longer also had a lower risk of heart disease during the follow-up period, with this risk increasing as walking duration decreased.

Borja del Pozo Cruz, co-lead author of the study, professor and researcher at the Department of Sports Sciences at the European University of Madrid, calls the four walking durations “doses.”

“There is a clear dose-response relationship,” del Pozo Cruz said. “The longer the fight, the better the different health outcomes we analyzed. »

The decision to study people’s health via step accumulation models, as opposed to total steps or intensity of physical activity, was intentional, he said.

“It’s easy to translate; everyone understands the steps,” del Pozo Cruz said. “Essentially anyone can measure steps with their smartwatch, smartphone, pedometer or whatever. We thought focusing on steps would be much more impactful because they translate immediately.”

Forget “exercise snacks” and 10,000 steps a day

The idea that adults should strive to get 10,000 steps a day is more of a marketing ploy to sell fitness trackers than a scientific guideline, according to Steven Riechman, an associate professor in the department of kinesiology and sport management at Texas A&M University, who was not involved in the study.

Riechman said the body goes through a number of adaptations when switching from rest mode to exercise mode — changes that take a little time. This could explain why people who walked for periods of less than five minutes didn’t see significant health gains, he said.

“You have to get all the systems engaged and fully operational, and that’s where the health benefits come from,” Riechman said. “The one I particularly thought about, [which] What the article doesn’t mention is that the increase in body temperature is unlikely to occur in less than five minutes of walking.

Despite mixed research on the health benefits of 10,000 steps per day, the study considered people who achieved an average daily step count below 8,000 to be “suboptimal active.” All study participants took fewer than 8,000 steps per day, and those who took fewer than 5,000 were considered sedentary. The median activity of all participants was 5,165 steps per day.

The link between longer periods of walking and lower risks of premature death and heart disease was most notable among sedentary participants, the researchers found. Within this group, people who walked for periods of less than five minutes had a 5.13% risk of death during the study period, compared to a 0.86% risk for people who walked for more than 15 minutes. Their risk of developing heart disease during the decade-long study period was 15.39% and 6.89%, respectively.

“You get big returns from zero to something,” Riechman said. “Then you continue to receive benefits, but they get lower and lower. By the time you reach 10,000 [steps]you don’t accrue too many extra benefits.

The study contradicts previous research that touts “exercise snacks,” or bursts of physical activity lasting less than five minutes. For example, a study published earlier this month in the British Journal of Sports Medicine found that exercise snacks improved the fitness of physically inactive adults. However, this study defined short bursts as structured, moderate to vigorous activity. The short spurts in del Pozo Cruz’s study, on the other hand, included the unstructured, low-intensity steps that one could accumulate throughout the day.

“Every step counts,” according to the American Heart Association, a mantra Riechman supports. Some physical activity is always better than nothing.

“Going out and taking some steps, sure, there’s definitely a benefit,” he said. “To me, you’re just not maximizing the benefits.”

“Never too late” to start walking

The study had several limitations, including the fact that 97% of participants were white.

Another research constraint is that participants’ walking habits represent a snapshot in time and people’s exercise habits can fluctuate over the years. Even so, the study’s large sample size likely stabilized this variation, said Carmen Swain, director of the health and exercise sciences program at Ohio State University, who was not involved in the research.

One of the biggest strengths of the study, she said, is the average age of the participants: 62 years old. It’s a time of life when people may think they’re past the point of reducing their risk of heart disease and premature death.

“You can start [walking] at any age; it’s not too late,” Swain said. “The physiological adaptations that happen in a 20-year-old are also going to happen in a 60-year-old.”

Yes, a 60-year-old may already have underlying signs of heart disease, she said, which is why it’s even more important for older adults to maintain a walking regimen.

“Unfortunately, it’s often a challenge for this population to get started because they haven’t done it in so long,” said Swain, who teaches her students the power of walking. “You need motivation. »

With heart disease being the leading cause of death among men and women in the United States, Swain hopes the heart health benefits of walking will be motivation enough.

“Walking is so democratic. You can do it wherever you want, when you want and how you want,” she said. “It’s a good form of exercise.”