Originally Posted by
2manybikes
a jogger moving at about 2.5 miles per hour was likely to come into contact with the slipstream, and thus, the droplets, of someone exercising as much as 50 feet ahead.
The study suggests that runners and cyclists may want to avoid moving directly behind another person and falling into their slipstream, Blocken said, by moving side by side or by in a staggered formation.
The principle sounds right, but that's a plume with a hang time of 14 s and has to assume no breeze at all. It translates to a 410' plume for a cyclist traveling at 20 mph, but with a lower concentration of aerosol. That's just not something I can act on rationally.