A new study found a link between climate change and physical activity, suggesting that rising temperatures may inspire people to get off the couch.
The research explores how human activity evolves in an increasingly warmer environment and sheds new light into how climate change impacts human health.
Study lead author Nick Obradovich, a postdoctoral fellow at Harvard Kennedy School's Belfer Center, first got the idea to investigate how temperature fluctuations influence the degree of physical activity in given areas after a heat wave in San Diego interfered with his daily run routine.
His study, featured April 24 in the journal Nature Human Behaviour, documents how global warming may alter people's willingness to exercise by analyzing "the relationship between meteorological conditions, physical activity and future climate change."
"It's a small little tiny silver lining amid a series of very bad, very unfortunate events that are likely to occur," said Obradovich, who also studies the social impacts of climate change at MIT.
What The Study Found
Initially, Obradovich assumed warming temperatures would keep Americans confined indoors, glued to their air conditioning systems. In a surprising turn of events, data revealed quite the opposite.
Inviting temperatures between 82 and 84 degrees Fahrenheit inspired people to go out more, translating into an increase in outdoor physical activity.
However, excessively hot temperatures of more than 95 degrees Fahrenheit led to a decline in exercise, particularly in people aged over 65 or those who are clinically obese.
This proves there is such a thing as an optimal temperature for exercise, and when it's too hot outside, people become less active.
"Using data on reported participation in recreational physical activity from over 1.9 million U.S. survey respondents between 2002 and 2012, coupled with daily meteorological data, we show that both cold and acutely hot temperatures, as well as precipitation days, reduce physical activity," Obradovich and his colleague James Fowler, from the University of California, state in their paper's abstract.
"I don't want to imply at all that warming the climate global warming is a good way of increasing physical activity," Obradovich said in a statement, adding that "it is probably the worst strategy to get people more physically active."
The researchers emphasizes that any overall benefit will probably be far outweighed by the many other ways climate change negatively affects health.
"Most of the climate impacts are going to be acutely negative and very costly. Anytime you look at the effect of a complex system change like climate change on other complex systems like human behavior, you're going to see a distribution of effects — and in this case, there's some very small positive," explained Obradovich.
How Climate Change Can Impact Human Physical Activity In The Future
By consulting the NASA Earth Exchange and accessing the projected average monthly maximum temperatures for 2050 and 2099, Obradovich and Fowler were able to combine their "historical estimates with output from 21 climate models and project the possible physical activity effects of future climatic changes."
According to the study, both location and season will play a crucial role in influencing outdoor exercise among Americans in the context of future global warming.
"Our projection indicates that warming over the course of this century may increase net recreational physical activity in the United States," show the authors in their paper, adding that physical activity "may increase most during the winter in northern states and decline most during the summer in southern states."
Regional climates characterized by less chilly winters will increase the likelihood of Americans spending more time outdoors, leading to a 2.5 percent boost in exercise by the end of the century amid residents of the cooler, northern states.
The research points out the most likely candidates for a dramatic increase in physical activity are the northern areas, such as North Dakota, Minnesota, and Maine.
Conversely, southern states are more likely to witness the steepest drop in outdoor activity by the year 2099, due to hotter summers. Places such as Arizona, southern Nevada, and southeastern California have the most chances of recording a decrease in exercise among their residents.
By the end of the century, July, August, and September will mark the months with the least outdoor exercise throughout the United States, whereas the year 2099 is expected to bring a boom in activity during November, December, January, February, March, and even April.