The answer is no!
A couple posts back I talked about different options of meals to eat before a workout. I’ve had multiple people ask me sense then about the idea that if you don’t eat before a workout it will force your body to burn fat instead. While I can’t blame them for asking good questions, I hate to say that this is not a true fact, or a good idea either!
I’ll start with why this is an untrue myth. During low intensity exercise (below 30% VO2 max) the body burns more energy from fats than from carbs. This is exactly what you want, but at low intensity the amount of calories that you are burning is also very low. Somewhere toward 40% of your VO2 max your body switched to burning more carbs than fats, maybe 60% carbs. The vast majority of workouts are actually going to be at least 40% of your VO2max because they are burning the most calories and getting your heart rate up. What you don’t what to have happen is your body not have any carbs to burn because the body won’t rely heavily on fats, it will actually keep the same percentage of fat and turn to something else. This leads to why it is a bad idea and that is because you will feel dizzy, sluggish, faint, or nauseous when you don’t eat before a workout. Your body needs energy to burn, so allow it to burn both carbs and fat together and get the most out of every workout.