Some people find that eating before exercising in the morning totally fuels their workout. (I, for one, need to eat something if I plan on even making it through the warm-up.) But others avoid gobbling up because they believe it makes them feel sluggish or causes cramps. So which way is right? Well, according to one recent study, eating a pre-workout meal could actually hurt your fitness goals.
For the study published in the American Journal of Physiology: Endocrinology and Metabolism, researchers enlisted 10 overweight men aged 18 to 35 to participate in two different scenarios: exercising for 60 minutes on an empty stomach and exercising two hours after eating a high-calorie, high-carb breakfast.
After analyzing blood and fat tissue samples taken before and after the men exercised, researchers found that when they worked out on an empty stomach, they fueled their workouts by burning stored fat, which can help shed pounds. When they did eat breakfast, on the other hand, the results changed: Their bodies were focused on breaking down the food they just ate, not breaking down fat.
“After eating, adipose (fat) tissue is busy responding to the meal, and a bout of exercise at this time will not stimulate the same [beneficial] changes in adipose tissue,” study co-author Dylan Thompson, PhD, says in a press release. “This means that exercise in a fasted state might provoke more favorable changes in adipose tissue, and this could be beneficial for health in the long-term.”
But that doesn’t mean you should straight-up fast before every sweat sesh: Even though the study found having breakfast before exercising might make your workout less effective, these participants also ate a pretty hefty meal of white bread, cornflakes, milk, orange juice, butter, jam, and sugar. Yeah, not the healthiest mix—and eating all of that would lead to a very full stomach.
So if you find that eating something small—like a banana or a protein bar—helps keep your stomach happy and your energy level strong during morning workouts, it’s probably not worth changing your routine. You just might want to avoid a three-course meal until after your sweat sesh.
More from Well + Good: