Weight gain is one of the documented side effects of invega sustenna; if you are on it, you aren't going to lose weight unless you work hard at it. I suggest you talk to your doctor and see what kind of weight-loss plan you can devise. Also, one form of exercise that does chip off the weight slowly but surely, is walking. If workouts are too much or too hard to keep up, try building a walking pattern into every day. (Park further from your work or school and walk the difference, etc.) Or just walk every night.