
Originally Posted by
CowPimp
To improve the definition of your muscles you have two choices: lose bodyfat or gain muscle. Seeing as how you are 12, I would not be trying to lose weight. I would be focused on lifting and eating like crazy. It's great that you're starting young.
Also, from the looks of your stats you aren't training your legs. Try this beginner's routine that I have laid out and I bet you will start progressing much better in terms of strength, size, and even probably improve definition:
Day A:
Olympic Squats 3 x 8-12
Chinups 3 x 8-12
Bench Press 3 x 8-12
Hyperextensions 3 x 12-15
Day B:
Deadlifts 3 x 8-12
Bent Rows 3 x 8-12
Military Press 3 x 8-12
Decline Situps 3 x 12-15