Getting in 9,000 to 10,000 daily steps cuts risk of death by more than a third and reduced cardiovascular disease risk by at least 20 percent, but even smaller increases showed benefits, researchers found in a study of more than 72,000 people.
“Any activity is good activity. We found the more steps you did per day, the lower your risk of mortality and cardiovascular disease was,” says Matthew Ahmadi, an epidemiologist at the University of Sydney in Australia and one of the study’s authors. “The 10,000 mark is a great target to hit, but even if you aren’t able to hit that, still doing any amount of activity to increase your daily steps can go a long way to improving your health and lowering your risk of disease.”
Ashley Goodwin, an exercise scientist at the Feinstein Institutes for Medical Research in Manhasset, New York, says the study really builds on the evidence we already know about how walking can help lower cardiovascular risk and mortality.
Goodwin found it especially interesting that the benefit differed so little between those who sat for long periods each day and those who sat less.
“That’s really great because it drives home the message that simply walking a little bit more than you usually do is going to confer some health benefits, no matter where you’re starting from.”
Past research had shown that higher step counts are linked to better heart health and a longer life, and a separate body of research has shown the increased risks of cardiovascular disease and death associated with more sedentary time. But this study brought those bodies of research together to learn whether extra daily steps could offset the risks of sedentary behavior even in those who spend much of the day seated.
Ahmadi’s team chose 10.5 hours per day as the threshold for “highly sedentary” because their data found the risks of sitting for more hours than that per day begin increasing exponentially. They compared the cardiovascular and mortality risks of different daily step counts to those of 2,200 daily steps—which is the daily maximum for 5 percent of the study population.
Every extra step helpsThe results show that both highly sedentary and less sedentary people had statistically similar risk reductions from higher step counts. But the findings also reveal a dose-response relationship, which means the more steps people had per day, the more their risk of heart disease or death fell, up until about 9,000 to 9,700 daily steps for highly sedentary people.
In fact, highly sedentary people in the study began experiencing a heart benefit starting as low as 4,300 steps per day, when their risk of heart disease fell by 10 percent. Doubling that step count to 9,700 steps a day doubled the benefit.
Similarly, highly sedentary people began seeing a 20 percent reduced risk of death starting at 4,100 steps per day. Again, that benefit nearly doubled to 39 percent when their daily step count increased to 9,000. By about 6,000 daily steps, highly sedentary people got the same benefit as more active people.
The average American gets about 4,000 steps a day, says Mario Garcia, a cardiologist at Montefiore Medical Center in New York City, so there’s plenty of room for improvement.
“Especially now that, in the post-pandemic era, we’re doing more remote working and spending more time at home, it’s important to be mindful of the time we are not physically active and try to compensate by something simple, which is walking,” Garcia says. He pointed out that individuals over age 60 benefited most in the study, probably because people tend to decondition very quickly as they age.
Ways to increase daily stepsAhmadi says a key takeaway from the study is that people who cannot reduce their sedentary time can still benefit by boosting their daily steps.
“Because there’s now been a recent increase in the proliferation of wearables among the population, it becomes much easier now to track daily steps,” Ahmadi says.
But it’s not necessary to go from 2,000 steps a day to 10,000 overnight, Goodwin says. In fact, she’s conducting a study that encourages participants to increase their average daily steps by just 1,000 more steps a day. That’s how many additional daily steps a 2020 systematic review of 17 studies found would reduce risk of heart disease and the risk of death from any cause over the next four to six years.
For those who dislike walking, Goodwin suggests other ways to get in those extra daily steps. “The best physical activity you can do is the one that you will do,” she says.
That could include other types of activities or squeezing in extra steps throughout the day, such as parking further away in the parking lot, taking the stairs instead of the elevator for a couple floors, or getting off public transit a stop or two early and walking the rest of the way. At the very least, Goodwin pointed out that an extra 1,000 steps a day is only about 10 minutes of walking, which fits into nearly any ambulatory person’s daily schedule.
Another way to increase steps is to focus on weekly counts instead of daily ones. Evan Brittain, a cardiologist at Vanderbilt University Medical Center who has studied the benefits of daily steps for years, says other data from this same study population show “that the ‘weekend warrior’ people are basically the same as the people who are regularly active” each day in terms of the benefits they reap.
But consistency is key, he adds, especially after the novelty of using a tracker wears off since people often initially change their behavior when they know they’re being observed. Data from a different, unpublished study, which tracked people’s activity over several years, found that only about half the people who started out as ‘weekend warriors’ kept that higher level of weekend activity in later weeks.
Brittain also remains skeptical that this study settles the debate over whether increasing step counts can offset sedentary behavior, given the data’s limitations.
“The idea that three to seven days of monitoring is reflective of your typical behavior over weeks, months, or years is really hard to extrapolate,” Brittain says. “It may be true for some people, but it seems unlikely to be true for everyone.”
How the study was doneThe researchers gave more than 100,000 adults in a large, ongoing U.K. study a highly accurate accelerometer (basically a more precise pedometer) to wear on their wrists 24 hours a day for a week. Then they analyzed data from the 72,174 participants who wore the device at least 3 days, including a weekend day, for at least 16 hours day—including while sleeping. The participants were an average 61 years old, and the researchers tracked their cardiovascular and death outcomes for an average of seven years.
They adjusted their analysis to account for differences between the participants, including age, sex, ethnicity, educational level, smoking status, alcohol consumption, fruit and vegetable servings per day, family history of cardiovascular disease or cancer, hours of sleep per night, and use of insulin (for diabetes) or medication for high cholesterol or high blood pressure.
“Sometimes you don’t know whether the individual who does more physical activity has better outcomes because they do more physical activity or because they have less diabetes, high cholesterol, high blood pressure or other risk factors that increase the risk of a cardiovascular event,” Garcia says. But this study accounted for those variables, he says.
What the researchers could not account for was whether people might have substantially changed their activity levels years later, Ahmadi acknowledges. But they did examine data from a small subset of study participants who wore the step counters again about two to four years later, and their activity levels stayed consistent.
That does not mean everyone’s activity levels remained consistent over time, Brittain says, but despite that limitation, he agrees with Ahmadi about the study’s most important message. “The main takeaway with all this [research] is that more is better, and the lower bound for benefit is probably lower than most people expect,” Brittain says. “That, I think, is empowering.”
Source : National Geographic