Jogging in Traffic is Bad Exercise

Jogging in traffic, at least, jogging in the kind of traffic that belches diesel exhaust, is bad for your heart, according to a recent and unsurprising study conducted at the Centre for Cardiovascular Sciences at the University of Edinburgh. U.S. News and World Report reports that the study looked at 20 men, all of whom had suffered a heart
attack in the past but whose heart disease was stable. All participants
were exposed to diluted diesel exhaust or filtered air for one hour
both while resting and while riding an exercise bike. The magazine reports that heart rates increased in both environments, but those in the diesel exhaust had lowered blood flow to the heart. The diesel exhaust also reduced the release of
endothelial tissue plasminogen activator, a "clot buster." Researchers worry that in the real word, the effects may be even worse.
Read more in U.S. News and World Report.
Read an abstract in the New England Journal of Medicine.