It may be a good idea to give one another more than six feet of space while exercising outside during the current coronavirus pandemic, according to a compelling new study that looked at how air flows around bodies in motion. The study has not yet been published in a peer-reviewed journal and the results need further confirmation. But they indicate that runners and brisk walkers may create a wake of air behind them that could carry exhaled respiratory droplets for 15 feet or more, meaning that the droplets could reach people walking or jogging well behind them.
The findings, released last week as a brief white paper and accompanying series of animations, have been shared widely on social media and prompted some trepidation among people worried they demonstrate that sharing the outdoors with other exercisers, especially runners, raises infection risk. But the study, which has now been posted in full online, did not look at coronavirus particles specifically or how they are carried in respiratory droplets in real-life conditions. Nor does it prove or even suggest that infection risks rise if you do wind up temporarily strolling behind a panting runner.