Walking Lowers Mortality Rate in Older Women

A study published in this week's issue of JAMA Internal Medicine looked at the question of the benefits of walking 10,000 steps, and whether or not this (actually quite arbitrary) number impacts longevity in a select group of women. The investigators evaluated a cohort of over 16,000 women, all over age 72 years, over 7-day periods between 2011 and 2015. They gave them each a wearable device to measure steps during a given week. They then reviewed step data, to see if it correlated with all-cause mortality in the subsequent five to eight years, Forbes reported.

The study found that there was a decrease in all-cause mortality in women who walked as few as 4,400 steps per day, not the coveted 10,000. They also found that once a woman walked more than 7,500 steps per day, walking more than this did not correlate with lowered rate of death.

Granted, there are several weak spots in this study. One potential flaw is the accuracy of the step counts. Another is that it's measuring one aspect of lifestyle (walking steps) over a relatively short time (one week). But the large number of study subjects and long term follow-up (as long as eight years) gives some weight to this data.

The notion of steps per day being linked to health is not a new one. The Amish population, a close-knit community living primarily in Pennsylvania, Ohio, and in parts of Ontario, Canada, has been the subject of health studies from the vantage point of diet, genetics, lifestyle and exercise for decades. A 2004 study tracked steps of the Amish, and found that Amish men walked, on average, 18,000 steps per day, and Amish women were clocking approximately 14,000 daily steps. And while the Amish are hardly known for snacking on kale chips or sipping Kombucha, they tend to have extremely low rates of obesity and heart disease, despite a pretty hefty diet and dearth of pilates classes.

Japanese walking clubs in the 1960's and 1970's promoted use of pedometers, with the goal of 10,000 steps per day. This is an auspicious number in Japanese culture, but it is arbitrary, not an actual data-driven marker for healthy levels of activity for adults or children. More recent data shows that children should walk closer to 13,000 steps each day for ideal activity levels to maintain health.

Wearable technology continues to be more and more wearable and more and more technological. The wristbands are stylish, with more bling each shopping season, and there are even wearable technology rings, if bracelets aren't your thing. The data now extends miles beyond steps, to include heart rate, sleep patterns, inactivity alarms, and even electrocardiograms. Over 100 million devices are sold annually worldwide, and it is a billion dollar business.

Alas, simply wearing a health tracker does not equal having a healthy lifestyle. In fact, wearing one for the sake of losing weight may have the opposite effect. One 2016 study looking at close to 500 adults found that the addition of wearable technology during a weight-loss intervention resulted in losing less weight, not more, over a two-year period. The group wearing health trackers lost half as much weight as those who did not wear a tracker. Those wearing fitness trackers were also found to be less fit, as measure by degree of daily physical activity.

Accuracy of any tracker data has been questionable, with some overestimating step count by up to fifteen percent. But for those who engage in minimal physical activity, the trackers may, indeed, be motivational. And according to this recent study, walking much less than the sought-after 10,000 daily steps, especially into one's eighth decade, may be plenty to keep the internal tracker we call the heart ticking into the ninth decade and beyond.