If you don't work out in the morning
We suggest you have your main meal 2 - 4 hours before working out. Preferably, it contains all macros (carbs, fats and protein). Alternatively, you can have your snack 1 - 2 hours prior to working out. Your snack should combine protein with carbs, as fats need too long to digest.
If you work out in the morning
You can skip your breakfast if you had some carbs with your dinner the night before (potatoes, rice, whole grains, ...). If you didn't have some carbs for dinner, we suggest to have your breakfast before working out. If it's hard for you to work out on a full stomach, you can split your breakfast portion into two and have the other half after working out.
What about a post workout snack?
We only suggest you have a post workout snack if your goal is to gain muscle mass, if your workout was longer than one hour, or if it was very intense (such as heavy weight lifting).
You can read more in this great article!