WOW you must be in some awesome shape
Thank-you for your service to our country.
Many of us have found that lower carbohydrates is the key. Since most of the snack, dessert and junk food items are carb heavy, when I just cut those out of my diet (and be mindful of too much starch with my meals) I can usually meet my goals.
If you want a little encouragment (or an occassional kick in the butt) check out the exercise forums. There is a thread for running and walking, we'de be honored to have you join us.