Can't I just eat a banana and whey protein post workout?

It is quite obvious to experience such kind of doubts when one is on a weight loss regime. I will strongly recommend that you can just eat banana and whey protein post work out. But you need to understand that eating this diet must be kept to minimum. The ill effect of it can be that it will potentially lead to limiting the progress in getting true achievement of your performance and physique goals. It is a fact that the whey powder, when taken in concentrated or isolated form, takes longer time to digest. This further leads to delay in the time to reach the muscles. I would say that this type of sugar in bananas is not recommended for recovery. The ultimate reason behind it is that fruit carbs serve to refill liver glycogen, and leave for a less than optimal replenishment of muscle glycogen. It is much better at your age that you can indulge more towards any kind of physical activity in which you feel comfortable.