Q. Should marathon runners take a baby aspirin before a big race?
A. Probably, according to emerging scientific evidence. But not all doctors agree.
Marathon running can cause muscle injury that triggers production of inflammatory chemicals called cytokines. Cytokines boost activation of blood clotting agents called platelets, potentially raising the risk of clot-induced heart attacks, says Dr. Arthur Siegel, director of internal medicine at McLean Hospital in Belmont and a volunteer in the Boston Marathon medical tent.
In 2006, Siegel and colleagues reported in the journal of the American Society for Clinical Pathology that "during a race, a runner goes from the low risk to the high risk category for having an arterial thrombus [clot in an artery]." (The study used a blood test made by Bayer HealthCare, which makes aspirin.)