hi I am new here, I am 16 and 5'10 and 161 pounds I would like to get my core more toned for that daily I do 200-400 sit ups and I just started doing the leg raises. Am I doing any thing wrong? Any advise for me? Also I would like to get more defined all over. Also I do at least a half hour of cardio a day. I have been lifting weights for about 2 1/2 to 3 months.