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Exercise may block damage of a harmful personality

We know exercise can help improve even the most harmful of physical problems. Now a new study suggests being physically fit may erase the effects of a toxic temperament.

Researchers looked at the association between levels of aerobic fitness among type-A personalities--people often characterized as hostile, driven and aggressive--and levels of a clotting chemical in their blood called thromboxane. Thetype-A pattern of behavior has been implicated as an independent risk factor for coronary heart disease.

After putting 97 male students through blood, fitness and psychological tests, researchers found that thromboxane production was highest in unfit type A's. Thromboxane is a clotting chemical that strongly promotes platelet stickiness in blood, which can trigger heart attacks.

The type A's who were physically fit, however, had the same thromboxane levels as the type B's--people with calmer, less hostile personalities. This may mean that aerobic fitness helped make the angry blood chemistry safer (Behavioral Medicine, Spring 1992).

"People who appear to be type A show pretty high levels of thromboxane production," says Jon M. Gerard, Ph.D., from the department of pediatrics at the University of Manitoba, Winnepeg. "Right now it's speculation, but exercise may block that chemical, potentially preventing these men from having heart attacks."

This study was the first to tie behavior to a specific blood element known for boosting heart-disease risk. "It may be that this striving, competitive type-A personality is associated with a release of hormones and neurochemicals in response to a stressful lifestyle," says Dennis Dyck, Ph.D., professor of psychology at Washington State University, Medical Lake. "This hormone release may then harmfully act on thromboxane and other chemicals in a way that leads to a greater risk for clotting."

PHOTO: A man running with a walkman on. (ANGELO CAGGIANO/RSI)


By Greg Gutfeld

With Linda Rao and Maureen Sangiorgio

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