4 years since wls

I am very disapointed in myself, I have managed to gain back about 25 lbs in the past 2 years. After my surgery I worked at the hospital where I had my surgery and walked about 10 miles a day making rounds picking up Dr. orders. We moved in Aug 06 and my job here I have gradually moved up the ladder but the more I move up the more I sit at my desk, so therefore I do not get as much daily exercise as I want and need. Any suggestions?