This Is The Worst Thing You Can Eat Before A Workout, According To A Celebrity Trainer

The hardest part of working out, they say, is actually making it to the gym. (We can attest to the validity of this.) So, when you do get your butt to spin class, you want to make sure you’re getting the most out of your sweat session. That’s where nutrition comes in. There are some serious off-limits foods to keep in mind before you get to sweatin’—and they’re not all as obvious as pizza. In fact, most of them are actually healthy, but eating them pre-workout can hamper the effectiveness of your gym time.

We caught up with AKT founder Anna Kaiser, a celebrity trainer who’s worked with the likes of Shakira and Kelly Ripa, to get the scoop on what to eat before your workout—and what you should stay away from.

Eat This, Not That—Pre-Workout Edition

Flaxseeds contain fiber, which is normally great: unless you're about to sweat it out in the gym. "Too much fiber will cause gas and bloating," Anna explains.

One of the best things you can eat before a workout, she says, is "digestible carbs so that your body can process them easily and not take too much energy." She recommends noshing on one cup of oatmeal about an hour before your workout to reap the benefits of its vitamin B content, which helps your body convert carbs to energy. Bonus points if you combine it with coffee, green tea or matcha 15 minutes before your workout. This helps rev up your heartbeat, so it takes you less time to warm up, explains Anna. You'll also be more focused and present while you get in your reps.

Dark leafy greens are nutritional powerhouses, but if you eat them in the two-hour window before getting your fitness on, you're probably going to feel bloated. "Not great while you're working out," says Anna. And while you're at it, skip raw veggies in general before you hit the gym—they take a while for your body to break down.

One of Anna's favorite pre-workout snacks is a green juice with avocado. "You’ll get nutrients without the fiber, so it's easily digested and will give you a quick burst of energy," she says. (Note: When she says green juice, she means juice made with green veggies—no fruit. Fruit juice gives you the wrong kind of energy before a workout.)

Another reason to love avocados: They contain more potassium than bananas. "Potassium aids in maintaining nerve and muscle function," Anna says. Eat one 30 to 60 minutes before you work out.

Don't consume dairy within a two-hour window before your workout. "You'll feel that when you're working out," Anna adds. Many people have a tough time digesting it quickly, and it can make your stomach acidic—not a great feeling when you're trying to do burpees.

"An hour before I work out, I’ll take a plant protein with coconut water," Anna says. She likes Pure Protein Superfood Protein Powder. This combo is full of potassium, vitamins and nutrients, and it's easily digested so it won't hamper your workout.

You want to avoid anything that's heavy with protein and fiber—so save your banana-almond butter protein shake for a post-workout treat. Hummus and beans are also harder for your body to digest, which translates into bloating and gas.

The exception: plant protein, which Anna says is more easily processed.