A gym membership is not going to help you reach your goals. Contracts probably won't do the trick either. Neither will toys, tricks or textbooks. To reach your goals you need an exercise program. Perhaps you call it a training protocol, a movement practice or a fitness routine; it doesn't matter how you label it, every sustainable exercise program will have these three defining characteristics: skill acquisition- you gotta work towards ever more difficult skills, progressive strength training- if you're not getting stronger, you're getting weaker (& no body wants that,) communal- true habit change can only happen in a group (for 99% of us.)