What do I need to be a good line backer?

tehdrummer
In may, my high school is having tryouts for the football team, and I want to be a linebacker, because of inspiration from Brian Urlacher, who always has been my favorite athlete. As of now I am about 5' 10-11", and weigh 217 pounds. I am about 19% body fat, and I need to work on running faster. How can I do this? And what body other requirements might I need to full fill. If I tried out right at this moment, I would be a lineman definitely, so what should I do in regards to diet and exercise, and what body type should I reach? Any advice is much appreciated. Fyi, if you don't know anything about the subject matter then please don't answer, I want solid advice from people who know about this stuff. (I am doing a program called "Six Pack Shortcuts" which will get me in killer shape by then by the way, if I follow it.)
What do I need to be a good line backer?
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