WASHINGTON (Reuters) - Exercise can act like a drug on the
blood vessels, reducing the risk of heart disease by
literally getting the blood flowing, U.S. researchers said
It works in a surprising way, reducing inflammation, which
has recently joined high blood pressure and high
cholesterol as a leading known cause of heart disease, the
The blood stresses the walls of blood vessels as it passes
over them, reducing inflammation in a way similar to high
doses of steroids, the researchers report in Friday's issue
of Circulation Research.
"Inflammation in blood vessels has been linked to
atherosclerosis, a hardening of the arteries, and here we
see how the physical force of blood flow can cause cells to
produce their own anti-inflammatory response," Scott
Diamond of the University of Pennsylvania's Institute for
Medicine and Engineering, said in a statement.
"Conceivably, exercise provides the localized benefits of
glucocorticoids -- just as potent as high doses of
steroids, yet without all the systemic side effects of
taking the drugs themselves," added Diamond, who led the
"Perhaps this is a natural way in which exercise helps
protect the vessels, by stimulating an anti-inflammatory
program when the vessels are exposed to elevated blood
The findings could help explain why exercise works so well
to reduce the risk of heart disease, Diamond said.
"We're not talking about running a marathon here. We're
just talking about getting the blood moving at high
arterial levels," he said.
Studies in recent years have found that cells and chemicals
linked with inflammation can be found in arterial clogs,
and much research is now focusing on ways to reduce this
inflammation. For instance, teams are investigating whether
giving patients antibiotics or anti-inflammatory drugs
lowers their risk of heart disease.
Diamond has worked using human arteries in the lab but
wants to move into animals to confirm his hypothesis.
"Think of blood flow as a stream -- whenever a stream
branches off you get small areas of recirculation eddies or
pools of stagnant water," he said.
"These same situations of disturbed flow irritate the
endothelium (the lining of the blood vessels). When blood
vessels branch off, all the arterial flotsam -- fats and
activated blood cells -- can clump and stick at these hot
spots for atherosclerotic plaque formation," he added.
"Perhaps, elevated blood flow may alter these disease-prone
regions to relieve some of the localized inflammation."
Reuters News. Science. “Exercise Like a Drug in Heart
Disease, Study Finds.” Reuters. 23 Jan 2003. 24 Jan 2003.