This theory has been around for a good while now and seems to suggest that it is the best way to train! The idea is that by eating before you workout, your body will use this as fuel before dipping into stored energy.
But by training on an empty stomach, this fuel is not present and your body will use stored fuel E.g. body fat and also the over night fast will deplete muscle glycogen meaning you will start to burn fat sooner.
BUT let’s get one thing straight - if you’re looking to take part in an intense morning workout and your focus is to have the energy to perform at your best, this probably isn’t for you!
If you like to train near your maximum levels through workouts like HIIT, sprints, heavy weight lifting, you should ideally eat one or two hours before, or you’re likely to be off your best.
Fat takes longer to breakdown than carbohydrates so the more intense the exercise becomes the more the body will switch to a higher percentage of carbohydrates as fat breakdown can’t keep up with demand.
Most people who choose to exercise on an empty stomach, however, opt for some moderate form of cardio, such as jogging, biking or hitting the x-trainer.
BUT during these types of workouts, performance and calorie burn are about the same
regardless of whether you are in a fed or fasted state.