I’ve done a lot of stupid things in my life. Most of them having nothing to do with fitness and nutrition. But my nutrition blunders run especially deep.
I’ve done everything from waking up twice in the middle of the night to drink protein shakes (gotta eat every 3 hours, right?) to slugging 20-30g of BCAAs throughout the day to “stay anabolic” (this still feels like my “pet rock” moment).
When it comes to carb-loading, I’ve experimented with extremes: I’d wake up 2 hours prior to my workout and eat about 100-150g of carbohydrates. (Think: Two bowls of oatmeal + fruit + 2 slices of bread just to make sure my glycogen stores were “fully loaded” to build muscle.) And I once avoided carbs completely, because fasted exercise burns more fat, right? (Nope!)
The truth is always more about sustainable behaviors than trying to “hack” your body. For instance, fasted cardio does not burn more fat, but if you feel better doing it, then go for it. And carbs can help build more muscle, but you don’t need to eat yourself silly.
Still, the question remains for most:
Should you eat carbs before a workout?
From a scientific standpoint, research suggests a little bit of carb-loading can be a great thing for your workout performance.
The study, which was published in the Journal of Applied Physiology, compared endurance performance when consuming different amounts — and types — of carbohydrates.
The high-carb group ate 1.5g/kg of bodyweight before completing 90 minutes of intense exercise (think: a long run). This group saw better performance and were able to maintain their intensity for a longer period of time, whereas the lower-carb group had better fat oxidation, but were quicker to fatigue.
Looking at the results, it was a little murky to determine if the type of carbohydrate (low vs. high glycemic index) made any difference.
When to Carb Load
If you’re going to do long-lasting activity (especially endurance-type exercise, like running, biking, etc.) and performance is your goal (running longer, faster, and experiencing less fatigue), than pre-workout carbs is a better approach than avoiding carbs or going for a lower-carb meal.
In general, the longer the activity, the greater the “need” for carbs to help boost your workout.
But remember: if “forcing” your carbohydrate intake before a workout means you don’t work out, or makes you feel sick to your stomach, then don’t do it. Carb loading isn’t worth it if the meal that disrupts your workout.
Adam Bornstein is a New York Times bestselling author and, according to The Huffington Post, “one of the most inspiring sources in all of health and fitness.” An award-winning writer and editor, Bornstein was the Fitness and Nutrition editor for Men’s Health, Editorial Director at LIVESTRONG.com, and a columnist for SHAPE, Men’s Fitness, and Muscle & Fitness. He’s also a nutrition and fitness advisor for LeBron James, Cindy Crawford, Lindsey Vonn, and Arnold Schwarzenegger. His work has been featured in dozens of publications, including The New York Times, Fast Company, ESPN, and GQ, and he’s appeared on Good Morning America, The Today Show, E! News, and The Cheddar.