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Running / March 2021
Amy Reiter, Reebok Contributor

The 6 Worst Foods to Eat Before Running

Step away from those veggies and put down the milk. Experts say some foods—even healthy ones—can wreak havoc on your stomach during exercise.

The phrase “sorry to eat and run” usually has nothing to do with actual running. But if you eat the wrong thing before a run, sorry is exactly how you’ll feel (as well as nauseous, crampy and in desperate need of the nearest porta-potty). 
“Diet has everything to do with the quality of your run,” says Bonnie Taub-Dix, R.D., a New York City-based nutritionist and author of Read It Before You Eat It. Eating the wrong thing, she notes, can negatively affect endurance, performance and motivation, and may cause gastrointestinal discomfort.
Conversely, eating the right thing ahead of a run can enhance power, stamina and strength—and it sets you up for better recovery after your workout. “The goal of eating before exercising is to top off the stores of carbohydrates, called glycogen, in your muscles. This is the most efficient energy source for exercise, especially if you're going on a long run or want to hit a high intensity,” says Philadelphia-based sports dietitian Kelly Jones, R.D. “Depending on how long before your run you eat, you want either quick-acting carbs or a combination of quick- and slow-acting carbohydrates to ensure you have a steady supply of energy in your bloodstream so blood sugar doesn’t drop during exercise.”
If you’re fueling up a few hours before a run, look for foods with a mix of carbs, protein and healthy fats. “The macronutrients work together to support health and performance,” says nutrition consultant Alexandra Caspero, R.D., in St. Louis, MO. But timing is everything: As you get closer to your workout, you’ll want to cut back on fat, protein and fiber to prevent stomach upset. And some foods are best to avoid entirely before tossing on your running clothes and sneakers and hitting the trail or track. Of course, that begs the question: What should you eat instead? 
Here’s what the pros have to say about the worst—and best—foods to eat before a run. 

Skip it: Beans, lentils, other legumes

High in complex carbohydrates and fiber, these foods can take hours to digest and could cause gastrointestinal distress if you eat them less than half an hour before running. “This is not to say these foods shouldn’t be consumed at all,” Caspero clarifies. “But make sure you have at least a few hours before your workout.”
What to eat instead: “Look for foods that contain low amounts of fiber per serving,” Caspero advises. One good option: a saltine cracker spread with nut or seed butter.

Skip it: Broccoli, cauliflower, cabbage

Yes, they’re good for you. But not right before rubber hits the road. Known as cruciferous vegetables, broccoli, cauliflower, cabbage and Brussels sprouts are high in fiber, setting you up for digestive discomfort mid-run. Cruciferous veggies also contain carbohydrates called oligosaccharides. “Like fiber, oligosaccharides are not able to be digested by humans, so they pass into the large intestine where they are fermented,” Jones explains. “That’s why they make some people feel gassy.” 
What to eat instead: A bowl of oatmeal or cold cereal with non-dairy milk makes a great pre-workout snack, “maybe with a little fruit for some quick energy,” Taub-Dix suggests.

Skip it: Bacon, butter

Ditch the fried and fatty foods—or if you must, save them for your post-run brunch. (Really, you’d better.) “Foods high in saturated fat are more likely to cause GI discomfort than the unsaturated fats in plant foods,” says Jones. 
What to eat instead: “If you're looking to eat something within 5 to 15 minutes of exercise, reach for a tablespoon of honey, a ripe banana or two Medjool dates,” Jones says. “These will be absorbed into the bloodstream to help maintain blood sugar levels.” If your levels are low, your run will feel sluggish. Moreover, “you’re more likely to cut your run short and your perceived exertion level will be higher.” 

Skip it: Salsa and chips

"Eating spicy food before a high-impact activity makes you more likely to burp, causing discomfort in your esophagus,” says Jones. Spicy foods can also increase your thirst, cautions Taub-Dix, “and although staying hydrated is essential, you don’t want to overdrink before your run.” 
What to eat instead: Keep it bland and wholesome with a slice of turkey on a piece of whole-grain toast.

Skip it: Cheese

Dairy foods are high in protein and great for building strong bones, but can be difficult to digest, “especially for people who are lactose intolerant,” says Taub-Dix. On the other hand, not all dairy is created equal: Cheese, which has greater amounts of saturated fat, is a bigger problem than, say, yogurt, which “some people tolerate really well as a pre-workout snack,” says Jones. 
What to eat instead: Toss a non-dairy beverage, into your pre-run smoothie instead of cow’s milk. “You could also make a smoothie out of something like almond or peanut butter, your favorite fruits, veggies and ice,” says Taub-Dix.

Skip it: Candy, cookies, soda 

Sugary foods give you a quick hit of energy, but they can make your blood glucose levels soar and crash, zapping you of stamina mid-run. Even some protein bars can pack a sugary punch. 
What to eat instead: Choose foods with simple carbs or simple sugars from natural sources immediately ahead of a run. “These provide immediate energy to your body including your brain, organs and cells,” says Caspero. Try fruit, such as a banana or orange, a handful of dried fruit or some plain nonfat yogurt about 15 to 30 minutes before exercising. Drinking a small glass of 100% fruit juice is another solid choice.
Bottom line: Everyone’s food tolerance is different, and some people are more sensitive than others. But if you’re looking to minimize drama (and pit stops) on your next run, these six easy swaps are a good place to start.

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Running / March 2021
Amy Reiter, Reebok Contributor