I know two people that rarely pry there asses off the couch that have lost weight on a strict aktins diet. One that is lazy, one that has a serious lower back injury that prevents him from doing much of anything. Obviously, it would be better to include activity if it is possible. And, if they return to eating like they did they will probably gain more weight back than they lost. If they follow the atkins plan correctly, that is slowly add back carbs until their weight lose stops and keep it there they will be fine. If they cheat, or return to a *normal* diet, it will not work and is a waste of time.