MORNING WORKOUTS ARE awesome: Aside from the convenience of getting it done and being on with your day, first-thing-in-the-a.m. sessions have been shown to boost energy all day long. But one of the much-debated and heated arguments in the fitness and nutrition world revolves around whether or not you should eat before those early sessions. So, we spoke to the experts, combed through the latest research, and compiled the pros and cons of fasted workouts.
The pros of fasted workouts:
You may burn more fat
There’s some evidence that fasted cardio workouts (i.e., not eating before you hit the gym) can burn more fat. “Glycogen is the stored carbohydrate that your body uses as its preferred fuel source during exercise,” explains Men’s Fitness Training Director Sean Hyson. “The fasted cardio crowd says that because glycogen is somewhat depleted in the morning after the night’s fast, your body will burn a greater percentage of fat during training as its next resort. Most of us have some sort of meal within two hours before we go to bed and we rarely sleep for more than eight hours; so if you get up and start training 10 or so hours after your last meal, your glycogen will be low, but it won’t be gone. So it could be argued that you’ll have just enough glycogen left to train hard, but low enough levels that you’ll burn more fat than normal to compensate for it.”