Hi there :) I'd say it's personal, but it would be nice to work out as first thing in the morning. If you feel weak you could have something first, but leave actual breakfast as a treat after you've done your excersises, otherwise you could feel bloated and you could also feel cramps in your stomach or worse. Of course a lot depends on what you have for breakfast, how much time you give to your body before working out and what kind of workouts you're willing to perform. Anyway I think best choice is always empty stomach :)

If you are comfortable not eating before a workout and don't have any underlying health conditions (diabetes, etc), exercising in a fasted state (empty stomach) has been shown to have some great benefits like increasing production of hormones that help build muscle/burn fat and improving your insulin sensitivity. Morning workouts are the perfect opportunity to take advantage of this. Your body will begin to be able to use the calories you do take in more efficiently, including the energy stores you already have. Here's a quick read on intermittent fasting (I. F.) and working out: http://greatist.com/fitness/why-you-should-exercise-on-an-empty-stomach. Do more research online to get comfortable with how I.F. works and be sure to always listen to your body. If you feel light-headed or woozy during your workout, know that that is a sign you need to slow down and take in some calories. And of course don't forget to drink enough water.

I just have a light something like a protein shake or an apple, because working out when you're hungry sucks balls. At least for me it does. Then I have real breakfast when I'm done. I've lost 25 lbs so far so I don't think this method had been hurting.

I have my breakfast before I workout because if I workout on a empty stomach I get a horrible nauseous feeling but since I'm on a empty stomach I don't have anything to throw up.... It's horrible! But I noticed that not a lot of people have the breakfast, like a hefty meal before working out.

I do cardio most mornings before I eat, but have two breakfasts afterwards: