Researchers at Simon Frasier University, the University of Pennsylvania, and the University of North Carolina at Charlotte surveyed 1,277 workers at a large international financial consulting firm, measuring their work hours and asking them to rate on a 1 to 5 scale their agreement with statements like:
- "I feel guilty when I am not working on something."
- "I put myself under pressure with self-imposed deadlines when I work."
- "It is hard for me to relax when I am not working."
- "At my job, I feel strong and vigorous."
- "I am enthusiastic about my job."
- "When I am working, I forget everything else around me."
The survey also included behavioral and physical data, including headaches, stomach upsets, sinus problems, depression, sleep troubles, and fatigue.
One to two months later, 763 of the original study group were medically screened for the four primary risk factors for heart disease and diabetes: obesity, high blood pressure, cholesterol and triglycerides. The researchers
"found no association between work hours per se and either stress-related physical complaints, such as headaches or stomach upsets, or the four risk factors for heart disease and diabetes."
The researchers did, however, find health problems among people who worked long hours due to anxiety about the job, pressure from bosses or peers, or obsessive ambition that was tied to their sense of self-worth. These workaholics were:
"More subject to depression, sleeping problems, and fatigue than other workers and to such psychosomatic complaints as headaches, sinus congestion and stomach upsets... obesity, high blood pressure, and worrisome levels of blood cholesterol and triglycerides."
In other words, if you're working long hours because you're "in the flow" and enjoying yourself, you're not damaging your health, even if you find it difficult to relax after hours. However, if you're working long hours because you feel obligated to do so or because you're afraid not to do so, you're highly likely to be damaging your health.
From a management perspective, if you want your employees to work long hours and remain healthy, assign them jobs that they enjoy rather than encourage long work hours just for their own sake.
A word of warning, though. The study didn't examine whether long work hours increased productivity, either for the "engaged" employees or the workaholics. Other studies suggests that even with the right motivation, people become less efficient when they spend too much time at the job.