If you count your steps with a fitness monitor, you can now size up your competition. A new study lets you find out how your physical activity stacks up against the world.
If you’re clearing the 10,000-step threshold on a daily basis, you’re in the upper echelon of walkers, according to the study from researchers at Stanford University appearing in the journal Nature.
The breadth of the study is enormous. Researchers tracked the activity levels of more than 700,000 people around the world who used an activity app called Argus. Assessing 95 days’ worth of data per person, the researchers analyzed more than 68 million days of physical activity in total.
Breaking their findings down by geographic region, they discovered that Hong Kong led the way in per-capita steps, with an average of 6,880 per day. The United States was farther down the list, with about 4,700 steps per person per day.
Other countries, including China, Japan and Spain, achieved about 6,000 steps per day.
Varying levels of physical activity among a population may be associated with poor health outcomes, including obesity, according to the researchers. Specifically, they found that a high rate of discrepancy within a given population was tied to unhealthy weight.
“If you think about some people in a country as ‘activity rich’ and others as ‘activity poor,’ the size of the gap between them is a strong indicator of obesity levels in that society,” said Scott Delp, a bioengineer at Stanford University and co-author of the study.
The researchers also discovered that, in areas that showed poor-and-rich discrepancy rates, women were less likely to beat the pavement as often as men.
“When activity inequality is greatest, women’s activity is reduced much more dramatically than men’s activity, and thus the negative connections to obesity can affect women more greatly,” said Jure Leskovec, a computer scientist at Stanford.
Yet in countries where the discrepancy in physical activity among the population is small, the slowdown among women is negated as well.
“For instance, Sweden had one of the smallest gaps between activity rich and activity poor, and the smallest disparity between male and female steps,” said Tim Althoff, a doctoral candidate in Computer Science and first author on the Nature paper. “It also had one of the lowest rates of obesity.”
The research also assessed how “walkable” an environment is and how much of an impact that had on activity levels. To this point, they found a positive correlation.
“Looking at three California cities in close geographic proximity – San Francisco, San Jose and Fremont – we determined that San Francisco had both the highest walkability score and the lowest level of activity inequality,” said Jennifer Hicks, Director of Data Science for the Mobilize Center at Stanford. “In cities that are more walkable everyone tends to take more daily steps, whether male or female, young or old, healthy weight or obese.”
The Stanford team is sharing the study results and related data on the Activity Inequality website. They believe that their super-study is just the beginning in turning large-scale analysis into actionable decisions that can improve public health.
“With the appropriate apps and sensors we can push this research in exciting directions,” said Abby King, a professor of Medicine and of Health Research and Policy.
“We could better link activity within and across populations with food intake, or examine the ways activity and inactivity may affect stress or mental health, as well as investigating how best to fine-tune our environments to promote increased activity,” added King.