running is supposedly very efficient.

It's efficient in the cardio-sense, but like Abaddon mentioned its tough on the knees. Running on a treadmill is better. If you have the luxury, (school gym or whatever), you can swap out some running time for hard time on a stationary bicycle, which is obviously a lot better on ones knees.

you don't want to cut carbs completely, they are what your body uses to burn fat, and with out them your problem with the waist will not get any better. you'd just end up fatigueing yourself while not burning as much of the fat. i would reduce sugar if any thing, but i assume your already doing that. Or maybe try getting your protein from sources other than meat, such as beans.