This from the April 2009 issue of “Men’s Health:”
AS little as 20 minutes o fjogging along a well-trafficked street raises blood levels of volatile organic compounds, Autralian researchers report. They found that recreational runners suck in benzene, toluene, ethylbenzene and xylene – compounds that can cause respiratory illness – at a rate 4 times higher than bicyclists do and 10 times that of people at rest.
PLEASE stop running or performing any cardio in busy areas, which includes all of Chicago, New York, LA, San Francisco, etc. It just doesn’t make any sense.