i have like a flabby belly and i need to like build some muscle. i also have very flabby, thick thighs that need to get thinner (like slim down a bit). i'm 14 almost 15 years old and i weigh 122 at 5'7''. i just need some exercises that can work out my abs and other exercises that can workout my thighs. i am a dancer. i just need some to do quick and every night before i go to bed. oh yeah and i had spinal fusion 18 months ago so i'm not looking for an answer like "sit-ups". i need something easy on the back (can't involve severe twisting). thanks so much (: