When you exercise regularly it is important to plan your day ahead so that you don't eat at the wrong time.

That is because if you eat just before exercising you will not get the best results of your training.
But of course you have to eat before you exercise, you just shouldn't eat it right before you are about to go for a run for example.

By eating at certain times and having a light snack in between you can make sure that your training goes well.
A light snack can be some yogurt or a slice of whole wheat bread.

If I am about to go for a run I eat 2-3 hours before, something fiber rich like muesli and yogurt and preferably a fruit as well. Or I have my lunch which will be a more carbohydrate rich food.

It really isn't that complicated, still I see many people asking about this.