While most have heard of the recommendation, many of us aren’t quite as obsessed about getting 10,000 steps of daily activity as satirist and author David Sedaris. He describes trudging obsessively along the roads in Sussex, England just to feel that gratifying buzz from his wrist-worn device when he reached 10,000 steps.
That is why the release of a large study reporting that the health benefits of physical activity are apparent at levels far below 10,000 steps has the scientific community and the public buzzing with equal intensity.
The report describes a threshold of 4,400 steps per day that is associated with lower death rates for older women. While neither the scientific report nor the authors suggest that doing more activity is harmful, they do report declining benefits after 7,500 steps per day.
For the scientific community, these findings are what we hope will be the first of many to test long-held health recommendations that are based on beliefs rather than rigorous scientific studies. With the release of updated Physical Activity Guidelines in late 2018, came the call to use step count recommendations as a tool to change behaviors and ultimately improve health outcomes.
We are now one step closer.
I collaborate with researchers from the Centers for Disease Control and Prevention and around the world to describe the relationship between steps and mortality in observational studies, these recent findings highlight two important public health issues.
The first is that we may be able to release people from the overly ambitious goal of 10,000 steps for the vast majority of Americans who spend most of their time sitting on their couch or at their desk at work. Rather than signing up to run a marathon, most Americans need only to make minor lifestyle changes to improve their health.
Parking father way from the entrance of the store will not only spare your car doors but it will also promote weight maintenance and protect your heart. Taking short breaks from the computer to walk around the office could lower the risk of dying from the other leading causes of death including cancer and lung disease.
I once chaired a committee tasked with summarizing physical activity recommendations for cardiovascular protection when a colleague balked at the recommendation for 150 minutes of moderate to vigorous activity per week. By his reasoning, the recommendation was too low because people always do less than is recommended. To reach the goal that we want, he suggested we should challenge people to do more.
To be certain, that argument has merit when we look at the abysmal rates of compliance with healthy lifestyle recommendations in our country, but it also poses a risk that people may give up if they perceive the barriers are too high. It is a win that we can now suggest that as little as 2,000 extra steps can have health benefits.
The second important finding is that it is based on women. Women are less active than men on average. Disparities in activity between women and men emerge during early adolescence when girls leave the childhood playgrounds where they once ran and jumped alongside boys.
A pattern of lower activity for women as compared with men tracks throughout life that goes unchallenged by health professionals and the public, even without evidence suggesting that women experience fewer benefits of activity than men.
In fact, we suggest the opposite. Physically active women may live a shorter period of their overall lifespan burdened with cardiovascular diseases as compared with less active women. The influence of activity levels on cardiovascular disease was not nearly as strong among men.
What we do not know from the current study is whether these step count thresholds apply to men. What we do know is that we urgently need to encourage girls and women to remain physically active. We can accomplish this goal if we create safe spaces for girls and women to be active and broaden our definitions of activity beyond the competitive space to include social activities such as dance, gardening and walking.
Before we rewrite the guidelines, we need more and better studies. Critics are right to point out the mistakes from the past when basing clinical recommendations on observational studies. To avoid the seeming flip-flop from “all women should use hormone replacement” to “hormone replacement therapy may pose risks,” we need experimental studies that randomize research subjects to one exposure or another and follow them for outcomes.
However, randomized trials of lifestyle behaviors that take years to show benefits are not realistic or responsive to the rightful thirst for public health recommendations about activity. Sometimes we have to do the best with what we have. Today, what we have is compelling evidence that benefits of physical activity are achievable for most Americans with just a few additional steps per day.
Mercedes Carnethon Ph.D. is the Mary Harris Thompson Professor of Preventive Medicine and Chief of the Division of Epidemiology at the Northwestern University Feinberg School of Medicine. She is an NIH-funded researcher who studies the relationship of lifestyle behaviors on health and a Public Voices fellow with The OpEd Project.