Professor James Dwyer, of the Keck School of Medicine at the University of Southern California and lead investigator Cheryl Nordstrom studied 447 California utility-company workers, between the ages of 40 and 60, for three years.
The group included managers, meter readers, technicians and administrative assistants believed to be under increased stress as a result of rising competition in the industry after deregulation.
The study found that those presenting the most dramatic thickening of the carotid artery, a condition related to the buildup of plaque in arteries that can cause disease, were also in the group with the highest degree of workplace physical activity. The same group reported the most job-related stress.
On the other hand, employees who exercised at least four times each week outside of work showed much less carotid artery thickening than those who did no leisure exercise.