I don't know how your surgery/back problems relate to mine but I'm going to assume that they are somewhat similar. I had trouble training, walking, sitting, sleeping... living. I had severe nerve impingement, sciatic pain and massive leg pain on both sides all the way down to the foot. However, it did give me a good excuse to fly first class...I just told me wife I needed more room. More room for free alcohol.
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.