Pre Workout meals should consist primarily of protein and fats and very little or no carbohydrates. If you’re eating vegetables, this shouldn’t be a problem. Then Post Workout you should be having any meals with a higher carbohydrate content, whether it be sugars or complex carbohydrates. The closer you are to your workout, the more carbohydrates you should be consuming. So if you’re really looking at improving your body composition, you need to start focusing on a dynamic diet rather than a static diet. What I mean is, if you are working out today, that will change what you eat based on when you workout. If you’re not working out, you should probably focus more on fats and protein throughout the entire day. It doesn’t mean that small amounts of carbohydrates will hurt, it just means that carb rich meals (breads, rice, potatoes, PASTA) should be saved for Post Workout time periods.
If your workout schedule changes, your diet should change. Think about it this way, is your body doing the same thing on days you train on and days you don’t? If not, then why should you give it the same food/fuel?? It just doesn’t make sense.