Elizabeth Khalil has resolved not to give in to Office Gut.

But she knows it's not going to be easy.

For recent college grads, one of the hardest things about adapting to office life is the sheer inertia involved. It's an abrupt transition from running around on college campuses to sitting around in the average suburban office park, which isn't exactly pedestrian-friendly. (At one of my former jobs, people even had to drive to the next office park over to pick up lunch. A culvert blocked what would have been a five-minute walk; stepping out on the main road would have dropped you into a real-life game of Frogger.)

The lack of activity, coupled with one too many meals from the vending machine, can quickly make the Freshman 15 look like a bit of baby fat.

Much of the problem is the stress associated with the transition itself, said Carol Jack Scott, a Baltimore area physician who offers executive coaching and corporate training seminars about managing stress in the workplace.

The typical college student's lifestyle isn't exactly stress-free. The pressure, however, comes at scheduled intervals, especially the end of each semester -- and it's balanced by long breaks.

Before she graduated from law school, Khalil, 28, said she was used to exercising daily: running, two aerobics classes in a row, weightlifting, rowing. "A student schedule allows you so much time to do all that," she wrote in a recent e-mail. "Now I'm a lawyer for a government agency and also a freelance writer -- both occupations that involve lots of sitting."

It's a common scenario. A recent survey by CareerBuilder.com found that 47 percent of workers have gained weight since starting their current jobs.

Keeping healthy in the office is not impossible, though. It just takes effort. Here are a few tips to help keep you in good shape:

* Head off temptation. In some offices, it seems like every day is somebody's birthday, or wedding, or baby shower, or going-away part, or welcome party. You name it, someone's throwing a party for it, and handing out big slices of cake or piles of sugary doughnuts.

To keep her diet on track, Khalil makes sure to eat a little bit throughout the day, so she never gets desperate enough to scarf down junk food. "Some people try to lose weight by starving themselves; I just try not to ever be hungry," she said.

* Schedule regular exercise. No matter how busy you are at work, you still have to make time to work out. It will be harder when you no longer have access to a great (free) gym the way you did on campus, but you have to do it.

Khalil said she managed to keep the weight off by arranging her schedule so that she leaves work and heads straight to aerobics class. "I even decided to train to become an aerobics instructor to sort of push myself to the next level," she said. Another key part of her strategy has been to increase her weight training, "since muscle burns calories even when you're sitting around or sleeping."

* Move around. Perhaps more important than those scheduled workouts is your level of routine activity. If you drive to work, park farther from the door. If you take Metro or the bus, hop out a few stops early and walk the rest of the way. Take the stairs when feasible.

* Find ways to de-stress. Stress and weight gain are a vicious cycle. Are you feeling stressed because you've put on 15 extra pounds, or have you put on those pounds because you feel stressed? It can be hard to tease those two apart. "Stress is normal," Scott said. "Being stressed out is not."

Scott said it's important to distinguish between acute and chronic stressors. The acute kind can be painful and disruptive, but it's usually self-limiting. For young workers, that could be an incident such as getting fired.

Chronic stressors are potentially more harmful, and include things such as an abusive boss or a career that's a really poor fit for you. Young workers, however, have an advantage in handling those: They can head them off early, before the real damage is done.

And if you don't? You could wind up with something worse than Khalil's dreaded Office Gut.

Join Mary Ellen Slayter at 2 p.m. Sept. 2 for Career Track Live, an online discussion of issues affecting young workers, at www.washingtonpost.com/wp-dyn/liveonline/jobs/careertrack.