Whats the best exercise plan for a fast improvement?

Well, there is an exercise program. It is called "Insanity". As a 14 year old boy, an athlete, it is very challenging. I am not allowed to post websites, so Google "Try Insanity". Click on the first link, and watch any trial videos on the home page. All you need (if you buy the program) is a little bit of space, and work out clothing.