hi, i am 14 years old and weigh around 170 pounds. I am 5ft. 8. I have a little bit of a large stomach, and have a little too much fat on the legs. I was wondering, what should i do to lose the belly and some fat off the legs...I normally go to my gym 4 days a week. For the belly should i do a certain amount of crunches, or something? also, are there any machines you would recomend, like that Body By Jake Ab Scissor? THANKS