You may already know that bananas (ooh or dairy-free banana milk!) make for a good pre-run snack--and that grilled chicken is great for repairing muscles after lifting weights. But what about the foods that hinder your performance during a workout? Here, the eight offenders to skip (or save for later).

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Protein bars

There’s a reason why they taste so good. Most of these (deceivingly unhealthy) bars are loaded with sugar, which can cause you to crash quickly and leave you feeling sluggish in the middle of a workout. If you simply must grab a bar on the go, make sure it has a 1:1 ratio (or as close to it as possible) of protein to sugar, like the Nut Delight Kind Bar

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Leafy greens

For once we’re telling you to hold off on the healthy stuff like spinach and kale. (You too, broccoli!) Leafy greens are packed with fiber (which is normally a good thing), but not so great before a workout as it can cause gas and bloating. A better way to consume them before yoga class? Blend a handful into a pre-workout smoothie for easier digestion.

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Avocados

And here we thought they could do no wrong. Same goes for other good fats like olive oil and nuts. Because they're so slow to digest, they make your body compete with itself for blood supply, which can lead to cramping mid-workout. You're better off snacking on these after your early-morning bootcamp to add back in nutrients.

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Hummus

Or any other bean-based dip. (Remember that song from the second grade about beans being “the magical fruit”?) It’s because they’re complex carbs and, like leafy greens, are slower to digest, causing gas and bloating. As if spandex aren’t hard enough to put on as is….

RELATED: 9 Ways to Look Less Bloated by Tonight

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Anything spicy

Maybe save the Thai takeout for after your spin class. Spicy or even heavily flavored foods are difficult to digest and can induce heartburn or indigestion. Ever burp up Sriracha? Yeah, not an ideal scenario on a stationary bike.

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Or anything fried

This probably comes as no surprise, but fried foods are typically high in fat and salt, which not only makes you feel lethargic (hello, food coma), but also causes dehydration.

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Sports drinks

Though these drinks do have some vitamins and electrolytes, the high sugar content in them far outweighs any benefits. Stick to water unless you’re exercising intensely for over an hour.

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Nothing at all

We’re looking at you, early birds. While you probably don’t have much of an appetite at say, 6 a.m., you’re far better off having a small piece of fruit than trying to push through a workout on an empty stomach.

RELATED: What to Eat Pre- and Post-Workout

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