The study, published on May 29, 2019, in the journal JAMA Internal Medicine, found that older women (the average age was 72) who took 4,400 steps each day (about 2 miles, depending on the length of your stride) had a 41 percent lower rate of death than women who took 2,700 steps each day for the four-year follow up period of the study. Mortality gains for the women continued to grow until 7,500 steps a day, at which time the benefits seemed to plateau. RELATED: Everything You Need to Know About Physical Fitness “[The results] add to a large body of evidence showing that physical activity is good for health. Some is good; more is better,” says I-Min Lee, MD, epidemiologist in preventative medicine at Brigham and Women’s Hospital in Boston. And the findings should be encouraging to older women who are currently inactive, Dr. Lee adds — even taking as few as 4,400 steps per day appears to yield health benefits.
Data Shows More Steps Linked to Fewer Deaths
What’s unique about this research is that it looks specifically at steps, says Lee. “While we have many studies showing that physical activity is beneficial for health, there are few studies on steps and health — particularly long-term health outcomes,” she says. This research gap is one identified by the 2018 Physical Activity Advisory Committee, which the committee reported in the most recent physical activity guidelines, published by the U.S. Department of Health and Human Services (HHS). For this study, the researchers looked at 16,741 women with an average age of 72. Participants wore a research-grade accelerometer on their hips for seven consecutive days. The device measures motion and speed. “Seven days has been shown to be a good number to capture typical activity level in a person, since it covers both weekdays and weekend days,” Lee explains. (Additionally, repeated assessments over the following two to three years in a subgroup of participants in this study showed that the initial activity level recorded was a valid measure over time.) Unlike most activity tracking devices, the ones used in this study didn’t show the study participants how many steps they’d taken each day, because the researchers didn’t want those numbers to influence behavior. Researchers controlled for variables such as income, health habits, and weight. Although none of the participants reported poor health, personal and family medical history were recorded and controlled for in the analysis as well, because they could influence a person’s health and mortality. Researchers grouped the women into four quartiles according to how many steps they took. The median steps for quartile 1 (those who took the fewest steps) was an average of 2,718; median steps for quartile 2 was 4,363 steps on average; for quartile 3, 5,905 steps; and for quartile 4, 8,442 steps. After the initial week when steps were measured, all the women were followed for four years or longer between 2011 and 2015. During that period, 504 died. Lee and her team found that 275 out of the 504 women who died during the follow up period (more than one-half) were part of the least active quartile. Women in the second quartile, the group who averaged 4,400 steps a day, had a 41 percent lower rate of death than the lowest activity group. And the more someone walked beyond that threshold of 4,400 steps, the more they continued to lower mortality risk, but that trend plateaued for women who took more than 7,500 steps a day (and the benefit of additional steps ceased). The pace that women walked didn’t impact overall mortality, says Lee.
More Physical Activity Linked to More Benefits, but the Bottom Line Is That Some Activity Is Better Than None
We often hear the number 10,000 steps cited as a daily goal, but it’s not clear where this number came from, says Lee. (One potential origin is that it was a marketing tool created in 1965 by the Yamasa Clock and Instrument Company in Japan, the researchers note in the study. The company sold a pedometer called “Manpo-kei,” which means “ten thousand steps meter” in Japanese.) “For many older people, 10,000 steps per day can be a very daunting goal; thus, we wanted to investigate whether this was necessary for lower mortality rates in older women,” Lee explains. The average person living in the United States takes less than one-half that amount, according to research conducted at Stanford University published in July 2017 in the journal Nature, which found that Americans take about 4,774 steps a day on average. The new findings are consistent with guidelines that we recommend to people when it comes to physical activity — that more is generally better for health, explains Kerry J. Stewart, EdD, director of clinical and research exercise physiology at John Hopkins Medicine in Baltimore. “It’s another piece of data that makes the message about being active even stronger,” says Dr. Stewart. Specifically, walking helps build cardiovascular strength, helps control blood pressure, helps reduce LDL (or “bad”) cholesterol levels, helps with glucose control (in people with and without diabetes), and promotes bone density, Stewart says. Research has also linked more steps per day with lower body mass index (BMI). A study published in the Journal of Women’s Health found that women who took 5,000 to 7,500 steps a day had a significantly lower BMI than those who took fewer than 5,000 steps a day. He adds that while walking is an important part of physical activity, especially in older adults, it’s important to also incorporate other types of aerobic activity, as well as resistance training. And no many how many steps you’re getting per day or how much other exercise you’re doing, it’s important to know there’s a growing body of research that shows that being sedentary may have negative health consequences regardless of that other activity (according to the 2018 HHS physical activity guidelines, published in November 2018 in the Journal of the American Medical Association). RELATED: Everything You Need to Know About Exercise and How to Start Stewart says that people shouldn’t necessarily base their activity or step goals solely on the results of this research. It was designed as an observational study to compare the relationship between mortality and daily steps. It wasn’t designed to determine the optimal number of steps older women should be taking every day, he explains. The takeaway from this data is that more steps appears to help older women live longer. For older women who are currently inactive, getting up to taking 4,400 steps per day would be a big improvement, Stewart says. And if you’re already taking more steps than that, the benefit in terms of reducing mortality may be even greater, he says. Though it’s worth noting, if you have any injuries, medical condition that might limit your ability to exercise, or questions about your mobility, it’s a good idea to check with your doctor before making significant changes to your activity level.
