Personally, It depends very much on what my workout entails. If I am just going to lift then I have a HUGE pre workout breakfast about 1.5 -2 hours before my workout. This breakfast usually consists of 4 whole eggs, A LOT of veg, chicken, coconut oil, apple or banana, cashew butter and berries.
The reason I eat 1.5-2 hours before I workout is because when you train your muscles require more oxygen and glucose and so the arteries in these muscles vasodilate and so the arteries in your gut region vasoconstrict i.e reducing the amount of blood and therefore oxygen to these areas. This often results in stomach cramps or nausea during your workout as your body has not had enough time to digest your food.
Before a run, I eat a small breakfast of a large banana and cashew butter. This is because once I run more than 6km I begin to feel sick if I have eaten to much beforehand. After my run I come home and eat the rest of my breakfast, followed by another post workout meal about an hour later.
In Summary: - Eat 1.5-2 hours before workout
- A balanced meal with protein, carbs and fats should be consumed
- Energy levels have an accumulative effect, NOT what you have just consumed (mostly)
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