As a health writer, people often ask me if I've changed my lifestyle to become a healthier person. Do I eat healthier, work out more, and actually put to use any of those nifty tips I learn about every day?

For a long time, my response was, "No—I still have all the same bad habits; now I just feel guiltier about them."

I did eventually get involved in fitness and running, partially thanks to my job. But I still find it hard to squeeze in a workout most days, even though I know how important it is to my long-term health.

Turns out, I'm probably not the only health-related professional who feels that way. Most doctors, who know the dangers of inactivity more than anyone, don't get enough exercise, according to a study published this month in the British Journal of Sports Medicine.

Almost 80% of doctors fall short
Researchers at the United Kingdom's Bedford Hospital NHS Trust surveyed 61 hospital physicians and found that only 21% get the recommended 30 minutes of moderate exercise at least five days a week—that's less than half of the 44% of the overall population in the same age group who claim to meet this goal.

Those who didn't blamed lack of time, lack of motivation, or lack of workout facilities. (Doctors with an on-site gym at their hospital didn't fare any better than those without, however. In fact, a third of them didn't even know it existed!)

Other good habits had seemed to rub off on the junior doctors, who had an average age of 27 and an average BMI of 23.5 (considered normal weight): They weighed less and smoked less than the national average, and only 7% drank more than the recommended weekly amount of alcohol. As for their abysmal exercise habits, many had been more active in school—and had only become couch potatoes after they started their jobs.

What does it mean for us?
While the study was done on British hospital doctors (as opposed to, say, American primary-care physicians), coauthor Lampson Fan, MBBS, is willing to bet that findings would be similar elsewhere.

"In both the U.K. and U.S., doctors are under the influence of the same stresses," he wrote me in an email. "In many ways, its probably worse in the U.S. as the doctors there are working on average 30 hours more [a week] than those in the U.K."

While I can't say I'm shocked at these results, the numbers are quite disheartening. If doctors, whose responsibility it should be to promote good health, can't find time to exercise, what hope is there for others out there with demanding schedules—lawyers, truck drivers, working moms, or people who have taken on a second job?

Previous research has shown that doctors who exercise are more likely to counsel their patients to do the same, and that patients are more willing to try exercising when their doctors disclose their own personal workout habits. Think about it: If an out-of-shape doctor pleaded with you to get more exercise, how seriously could you take him knowing that he's not getting enough himself?

Dr. Lampson recommends that health-care institutions do more to promote physical activity among employees, such as sponsoring organized exercise classes, team sports, and discounts with local gyms. If doctors can get passionate about exercise, hopefully they'll pass on that excitement to their patients—or at least set a good example.

Does the physical fitness of your doctor matter to you? Have you ever been motivated—or discouraged—by the health of a physician?