Hardly anyone loves exercising in the festering crucible of a brutal summer heatwave. So it stands to reason that as global temperatures rise, the kind of physical activity that’s so crucial for our health and economic productivity could fall.
But recent research from Georgia Tech’s School of Economics in the Ivan Allen College of Liberal Arts suggests adding an asterisk to earlier research that makes that conclusion, saying previous studies failed to account for one simple fact: people adapt.
Georgia Tech economist Bobby Harris used a massive database of Fitbit step count data to measure how temperature shapes physical activity and found that extreme heat cuts step counts by 6% when compared to ideal weather. And while residents of the warmest regions cut their activity by an average of only 354 steps on days over 100 degrees, those living in the coldest regions cut theirs by 1,081, according to Harris’ analysis.
To be fair, cold bites, too. On days that stay below freezing, people take roughly 1,000 fewer steps. That’s a 12% drop, enough to pack on a pound over the course of a typical Madison, Wisconsin winter, Harris found.
But as the climate grows warmer, how humanity will respond to warmer temperatures remains a significant concern. In fact, earlier research projected that, by 2050, temperature-driven declines in physical activity could contribute to 500,000 premature deaths a year worldwide and annual productivity losses topping $2.4 billion.
Projections like those typically assume everyone responds to heat the same way, with no capacity to adapt, Harris said.