Let's say you're a young IT manager, in your 20s, 30s or even early 40s. It's not unheard of for you to put in 10-hour workdays in front of your computer, or some other user's.

You try to eat something at least halfway healthy when you make it to the company cafeteria, but most days, you're crashing by 4 p.m., which means a trip to ye olde vending machine for a Jolt or a Snickers (or both). By 6 p.m., you're sprawled out all over your desk, ergonomics be damned, still typing furiously (and simultaneously) on your laptop and BlackBerry, wondering if you'll ever get out the door.

Weekends mean family obligations, household chores and a few hours stolen here and there to catch up on key projects from work. There's no time or energy for exercise more rigorous than mowing the lawn or riding bikes with the kids.

In your heart of hearts, you know the long days, heavy workload, poor eating, lack of exercise and cruddy posture add up to a pretty stressful work environment -- and that's before factoring in your boss's notoriously short temper. But hey, you're young, you can handle it, right?

Wrong.

Fat, sore and stressed

Keep it up another 10 years, and you could be looking at a host of ailments, from nagging aches and pains on up through serious, life-threatening conditions, according to a host of medical experts we spoke with.

The combination of a sedentary workday and poor eating habits can lead first and foremost to obesity, which can put your heart at risk and lead to a litany of other diseases. According to the Centers for Disease Control and Prevention's National Health and Nutrition Examination Survey, in 2005-2006 the prevalence of obesity among adult men was 33.3% and 35.3% among adult women.

Obesity, in turn, increases the risk for conditions like hypertension (high blood pressure), Type 2 diabetes, stroke, gallbladder disease, sleep apnea, respiratory problems, certain cancers and cardiovascular disease.

"A phenomenal amount of people die [every year] from cardiovascular disease, which is very preventable," says Susan Levin, M.S., R.D., and a staff nutritionist at the Physicians Committee for Responsible Medicine, a Washington-based nonprofit organization. Desk-bound workers are particularly at risk, she says. "If you have risk factors -- you're male, you're a person of increasing age, you lead a sedentary lifestyle and you're overweight -- you need to take control."

The office life is also hard on your muscles and skeleton, thanks to the prolonged computer use that's so common among IT workers. When the body is still, circulation slows, reducing the supply of oxygen and nutrients to the muscles. This scenario, coupled with poor posture, can produce a number of musculoskeletal disorders (MSD), according to the National Institute for Occupational Safety and Health, which manifest with pain, tingling, discomfort, numbness and swelling in the joints and muscles. Most are temporary, but others can be permanent.