or years, federal have told Americans how much time they should spend moving each week: at least 150 minutes, or 75 minutes if workouts are particularly vigorous. But the popularity of wearable fitness devices has made many people obsessively track their step counts instead, often shooting for the goal of 10,000 per day (even though that number ). Is the length of your workout or your daily a better measure of wellness? “Both are good metrics,” says Dr.
Rikuta Hamaya, a preventive-medicine researcher at Brigham and Women’s Hospital in Boston and lead author of the new study. But Hamaya and his colleagues wanted to know if one was better than the other, so they designed a head-to-head comparison. The resulting , published in , is based on data from more than 14,000 U.
S. women who were tracked for about a decade. When the study began, the women were all at least 62 years old and free of cardiovascular disease and cancer.
They were asked to wear an activity monitor for a week, removing it only to sleep, shower, or swim. From those data, the researchers calculated how many steps people took per day, as well as how much time they spent doing moderate-to-vigorous physical activity like cycling, jogging, or walking quickly. : Among women in the study, the median number of daily steps was around 5,200, while the median physical-activity duration was about an hour per week.
People who exercised more also tended to walk more, but the two measures weren’t perfectly synced. That�.