If you do the Wii fit exercises seriously it will really give you a good workout. The jackknife crunches will tighten abs quickly. It also has yoga, aerobic exercises, even some boxing workouts. Main thing seems like with it is if you use the proper form like it shows it will give you a better workout. Also lets you track weight, BMI, and you can keep a log of what you did even if you weren't on the Wii(like when I jog). I think the big thing is though that you aren't just sitting in some gym working out bored. It keep you entertained and it will tell you do this, this, and this to achieve better abs or this this and this for stronger upper body.