Why Scarlett Johansson's Trainer Says Dark Chocolate Is the Perfect Pre-Workout Snack

One of the worst things you can feel before a workout is hungry. You're stuck with an impossible choice: whether to suck it up and hit the gym — knowing you're going to feel tired, weak, and uncomfortable, at best — or to get a snack, and then have to wait at least half an hour to digest so you don't upset your stomach. Pre-workout snacks can help, but many of the products you find in stores are loaded with sugar, caffeine, or both. You can make some snacks at home (these 15 are our favorites), but on a busy morning, whipping up a batch of energy balls probably isn't going to happen.

Eric and Ryan Johnson are the NSCA-certified celebrity personal trainers behind Homage Fitness; Eric is the trainer who got Scarlett Johansson into Black Widow shape for the Avengers movies. They have a radical new snack solution to help you through your workout: dark chocolate. Got it — we're sold. No explanation needed. Before you start sprinting down the nearest candy aisle, though, it's worth talking through what exactly is going on here. What makes chocolate — chocolate! — a better pre-workout snack than all those bars, chews, and gels you see in the store?

Why Should You Eat Chocolate Before a Workout?

First is the psychology of it: essentially, you're creating what Ryan called a "positive feedback loop." Chocolate has been shown to increase endorphin levels — a hormone that relieves stress and pain and causes feelings of euphoria — in your brain. This might sound familiar, because exercise does the same thing. When you pop in a couple pieces right before a workout, you'll start to associate that delicious taste and those happy feelings with heading to the gym. Once you're there, the exercise-induced endorphins will only emphasize that association even more. "You cut that dreadful, 'Ugh. I have to go to the gym right now,' mentality and start to create that, "'Oh, I'm excited. I'm going to the gym' mindset, just by eating this simple piece of dark chocolate," Ryan told POPSUGAR.

"We also find that a lot of clients are kind of unsure about whether they should eat or not eat before they go into a session," Ryan said — likely due to those negative side effects of either feeling too full and heavy if you eat something or feeling weak and fatigued if you don't. Dark chocolate, they found, hit the perfect balance: dense and nutritious enough to fill you up, but light in terms of volume and weight. "It doesn't sit in your stomach," he explained. "It keeps you nice and light but it gives you this big burst of energy that's well-sustained throughout the workout."

Of course, dark chocolate also has a good amount of caffeine. According to the USDA, one ounce (about 28 grams) of 45 to 59 percent cacao dark chocolate contains about 12 milligrams of caffeine — and the darker the chocolate, like the 80 percent cacao variation that Eric and Ryan recommended, the more caffeine it has. Getting your caffeine from a more natural source than your standard coffee or energy drink, Eric explained, is a better choice for overall health, as well as your workouts. Plus, dark chocolate contains theobromine, another stimulant that also works to dilate your blood vessels and decrease blood pressure.

Needed more proof? Science is on their side as well. A 2015 study from London's Kingston University found that having a bit of dark chocolate before a workout also helps you breathe easier and more efficiently during a workout.

What Kind of Chocolate Should You Eat Before a Workout?

This isn't an excuse to scarf down a bag of M&M's before a workout, though. Eric and Ryan specified that the chocolate should be organic, fair-trade, and most of all, dark: about 80 percent cacao or more, Ryan said. Aim to eat about 25 to 50 grams of it, depending on the intensity and length of your workout; that's about a third to a half of a standard-sized bar. You can eat it up to 20 to 30 minutes before the workout, Ryan said. "Sometimes if I'm in a rush, I'll be eating it as I warm up," he added.

They also recommended eating the chocolate slowly and savoring the taste to get the most out of the experience. "Let it kind of melt in your mouth a little bit, move it around and try to savor it more because that type of mindfulness can help you with your workout," said Ryan. Eating slowly also aids digestion, which will help you avoid mid-workout stomach upset.

You don't need an excuse to eat dark chocolate, but now you have one backed up by trainers and science. If you're ready to pick up a couple bars (or a cases), check out some of our favorite healthy chocolate brands, all available at Whole Foods.