The most important thing to understand when training athletes is the difference between G.P.P and S.P.P. Also, it's important to understand that mastery in a specific discipline does not mean mastery in weight training. In fact, it is usually the opposite; master of one thing, beginner of another. This is very lucky for you, whether you are a coach or an athlete. What this means is that you don't need advanced or fancy training methods to achieve results. Besides the huge pile of dung that is "sport specific training", the misunderstanding of training mastery by elite athletes is ruining training.