Hard Physical Labor May Boost Risk of Heart Disease, Stroke: Studies

You'll have to have your doctor decipher this.
http://www.doctorslounge.com/index.php/news/hd/37339
The findings suggest that people with physically demanding jobs should be considered an important target group for prevention of cardiovascular disease, said study author Dr. Demosthenes Panagiotakos, an associate professor of biostatistics and epidemiology at Harokopio University in Athens, Greece.
The results seem to conflict with recommendations that people should exercise to reduce their risk of heart trouble. But Panagiotakos said the increased risk of stroke and heart events among people with physically demanding jobs may be due to mental stress, while exercise helps reduce stress. He also said people with physically demanding jobs tend to have lower incomes, which might limit their access to health care.

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