See if there's any crossfit studio in your area. I joined mine a year or so ago when I was just a little shrimp. The changes that have occurred in that year are staggering, well worth the time and money. The workouts strain just about every part of your body almost every single time you go in. Completing just one of their workouts is an achievement for most. As soon as you get used to the type of exercises they throw at you it's so rewarding, and gets you in shape faster than you'd think was possible.