I've recently started a new job that requires me to sit a lot more throughout the day than I'm used to. I eat pretty well and exercise three to four times a week, but I feel like I'm getting, excuse the expression, a "secretary's derriere." Any suggestions on how to keep my metabolism going and control my weight?

The American College of Sports Medicine (ACSM has recently published workout guidelines for frequency (how many times a week), intensity (how hard) and duration (how long each time) that specifically address your question. The ACSM has found many health benefits to doing three shorter spurts of exercise if you don't have time to do an entire workout in one shot. The most effective way to boost your metabolism is exercise, and, according to the ACSM, adding up short bouts of activity can be just as effective as one long one when it come to certain health benefits.

So, if your job is more sedentary then you would like, aim for getting in three 10-minute workouts every day you can. How? If you drive to work, park as far away from the office as possible and walk the rest of the way. If you take public transportation, get off a stop or two early and walk the rest of the way. Or take a brisk walk during one of your breaks. These are just a few examples of additions to your overall activity level that will add up big time. For example, if you tack on 20 minutes of activity to your commute (10 minutes each way) and a 10-minute walk during one of your breaks, that would add up 30 minutes of additional activity every day. Think about it: That's 2 1/2 hours of exercise every week.

Another option is to see whether your employer can outfit your workstation with an adjustable tabletop so you can stand while you work. In addition to being more mentally stimulating, standing for short 20-30 minute periods each day will keep help strengthen your lower body and also may slow down the dreaded "spread." And did you know you also burn more calories standing than you do sitting? The average person burns about 100 calories an hour sitting and 140 calories an hour standing. That difference can really add up over time.

One more thing you may want to consider trying is to extend your normal three to four weekly workouts by an additional 10 percent to 15 percent. That will increase your total caloric expenditure for the week and help make up for the activity that your new job does not allow. Whatever you decide to do, start right away, enlist a friend for support, and stick with it.

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