These problems are at the heart of the two new studies, which analyze the links between activity and longevity from different but intersecting angles. The first of the studies, published this month at JAMA Network Open, focuses on the steps. Most of us know the daily step count as an activity goal, as our phones, smartphones, and other activity trackers typically force us to take a certain number of steps each day, often 10,000. But, as I wrote before, current science does not show that we need 10,000 steps for health or longevity.
Researchers at the University of Massachusetts at Amherst, the CDC and other institutions wondered if, on the other hand, smaller pass totals could be related to longer life. Therefore, they turned to data collected in recent years for a comprehensive and ongoing study of heart health and disease in middle-aged men and women. Most of the participants had joined the study about ten years earlier, when they were in their forties. At the time, they performed medical tests and carried an activity tracker to count the steps each day for a week.
Now, researchers obtained records from 2,110 participants and checked their names against death records. They found that 72 participants had died during the intervening decade, a relatively small number, but not surprising given the relative youth of the people. But scientists also noticed a strong association with step counting and mortality. Those men and women who accumulated at least 7,000 steps daily when they joined the study were about 50% less likely to have died than those who took less than 7,000 steps, and mortality risks continued to decline to as people’s footsteps increased, reaching 70 percent less chance of premature death among those taking more than 9,000 steps.
But in 10,000 steps, the benefits were reduced. “There was a point of decreased performance,” said Amanda Paluch, an assistant professor of kinesiology at the University of Massachusetts Amherst, who led the new study. People who take more than 10,000 steps a day, even many more, have rarely survived those who take at least 7,000.
It is useful that the second study, published in August in Mayo Clinic Proceedings, look at activity levels broadly similar to the best bets for a long life. This study included data from the study on the heart of the city of Copenhagen, which recruited tens of thousands of Danish adults since the 1970s and asked them how many hours a week they play sports or exercise, including cycling (very popular in Copenhagen), tennis, jogging, swimming, handball, weightlifting, badminton, football and others.