How 4,500 Steps Per Day Could Change Your Life
Walking has long been considered one of the "best medicines." But experts still debate the recommended "dose" for optimum health.
On many fitness trackers, the "magic number" is 10,000 steps per day. But new research suggests this number shouldn't be set in stone.
A recently published decade-long study suggests that walking at least 4,500 steps per day is the tipping point for reducing all-cause mortality.
Are you someone who believes that if some exercise is good, more exercise must be exponentially better? If so, it may be time to readjust your mindset. Like many things in life, the "Goldilocks zone" for reaping the benefits of physical activity lies somewhere in the middle between doing too little exercise and doing too much.
For decades, researchers have been trying to pinpoint the optimal dose (i.e., duration, frequency, intensity) of daily physical activity that hits the "sweet spot" for decreasing morbidity and increasing longevity.
Is It Time for Us to Rethink 10,000 Steps per Day as the Be-All and End-All?
Often, the all-or-nothing misconception that "I need take 10,000 steps per day to reap any benefits from walking" is overwhelming and demotivating; walking that much every day isn't feasible for many people. Hopefully, knowing that taking 4,500 steps per day could help you live longer will kickstart your motivation to walk a bit more every day.
That said, epidemiologists still aren't 100 percent sure about the ideal "dose" of daily physical activity that is associated with men and women of different ages—and from all walks of life—optimizing their psychological and physical well-being across a lifespan.
Although there is often heated debate about optimal exercise volumes based on seemingly contradictory research findings, the current World Health Organization (WHO) guidelines recommend that adults do at least 150 minutes of moderate-to-vigorous physical activity (MVPA) per week or accumulate 75 minutes of high-intensity physical activity (e.g., 15 minutes, five times a week). Plus, at least two full-body strength training sessions per week.
When it comes to walking, the gold standard seared into many people's brains (and the default setting on most fitness apps) is 10,000 steps per day. However, a growing body of evidence suggests that the life-preserving benefits of walking may kick in at just under half that amount, at about 4,500 steps per day.
On May 21, Christopher Moore, a Ph.D. student in epidemiology at the University of North Carolina at Chapel Hill, presented the latest findings from "The Women's Health Study" ( WHS ) virtually at the American Heart Association's Epidemiology, Prevention, Lifestyle and Cardiometabolic Health Conference 2021.
The WHS study of 16,732 women began in 1993 and is co-led by principal investigator I-Min Lee along with colleagues at Harvard's Brigham and Women's Hospital and other universities, such as UNC at Chapel Hill. One limitation of the WHS is that study participants were all over age 60 and primarily non-Hispanic white women; more research is needed to see if the same results from this study hold true for other ages and diverse groups.
Longer Daily Walks (> 10 Minutes) or Shorter Walks (< 10 minutes) Equalling at Least 4,500 Steps May Reduce All-Cause Mortality.
Data from the latest (2021) WHS analysis into the link between sporadic step accumulation and all-cause mortality was collected from 2011-2015, with a follow-up that tracked deaths from any cause through December 31, 2019.
Over the course of a decade, the research team led by senior author I-Min Lee of Harvard Medical School found that taking more steps per day, either all at once during a dedicated walk (more than 10 minutes) or in shorter spurts (less than 10 minutes) was associated with living longer.
As you can see by looking at the hockey-stick shaped curve in this graphical representation of the latest (2021) findings, study participants who took more steps in short spurts throughout the day tended to live longer—regardless of how many steps they'd taken in more prolonged, uninterrupted bouts of walking that lasted upwards of 10 minutes.
In the abstract of Moore's AHA presentation, the authors sum up: "Daily step counts were inversely associated with mortality regardless of how they were accumulated."
Notably, the all-cause mortality benefits of walking each day in short spurts or continuous bouts really kicked in at about 4,500 steps per day and leveled off soon thereafter. These findings corroborate a prior analysis ( Lee et al., 2019 ) from The Women's Health Study, which found that those who took 4,400 steps per day had a significantly lower risk of death when compared to those who only took 2,700 steps per day.
"Taking 10,000 steps a day can sound daunting. But we find that even a modest increase in steps taken is tied to significantly lower mortality in older women," I-Min Lee, an epidemiologist in the Division of Preventive Medicine at Brigham and Women's Hospital, said in a news release about her 2019 study. "We hope these findings provide encouragement for individuals for whom 10,000 steps a day may seem unattainable."