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You’re halfway through a workout and crushing it. Then, your stomach starts churning. You keep moving, figuring the discomfort will pass—but soon you’re doubled over in pain, desperately scanning for the nearest bathroom.
Experiencing this type of GI distress during exercise is “more common than people realize,” says sports dietitian Angie Asche, MS, RD, CSSD, founder of Eleat Sports Nutrition and author of Fuel Your Body: How to Cook and Eat for Peak Performance. There are a number of reasons why your stomach or bowels may misbehave mid-workout, including dehydration and eating too much protein, fat, and fiber shortly before you break a sweat, according to Jen Scott, RDN, LD, a Road Runners Club of America running coach.
Having a carb-rich snack before or during your workout can decrease your chances of an upset stomach, while also giving your body the energy it needs to perform its best. That’s because your body digests carbs and metabolizes them into glucose–the energy source for your muscles–more quickly than it does protein, fat, and fiber.
Quick caveat: Nutrition isn’t one-size-fits-all. Scott, for instance, has worked with hundreds of runners and says that people’s fueling plans differ from one person to the next. Factors including individual food intolerances and conditions like irritable bowel syndrome, Crohn’s disease, and celiac disease can impact what sits well for you. That said, “your gut is highly adaptable, and there is evidence you can actually ‘train the gut’ to better tolerate food and drinks around exercise,” Asche says. So just because you can’t stomach a mid-workout snack right now doesn’t mean you can’t gradually work your way up to it.
Below are five expert-recommended foods to eat during or within 60 minutes of starting a workout. For many, these foods will provide the quick energy you need without upsetting your system.
Oatmeal is a great source of carbs, offering 27 grams per serving with only 4 grams of fiber. Eating it before exercise can tame rowdy bowels, since the fiber in oatmeal is a soluble fiber called beta-glucan that attracts water, forms like a gel-like substance within your gut, and reduces your chances of diarrhea, explains Scott. Just be sure to use instant or traditional oats instead of the steel-cut variety, since the latter is higher in slow-to-digest fiber. Also, keep toppings simple (think: brown sugar, maple syrup, or bananas). “When you start adding things like seeds or nuts, you might get into that territory where it’s a little too much fat or protein,” Scott says.
Boiled, peeled, and salted potatoes are great exercise fuel. Peeling makes them low in fiber (a small potato has less than 3 grams) and salting helps replenish sodium lost through sweat, Scott says. In addition, potatoes contain resistant starch, a type of fiber that helps feed the good bacteria in your gut and can improve digestive health, Scott adds. Most athletes rely on potatoes as a pre-workout snack, but “I have seen runners pull them out of their pockets in marathons and eat them too,” Scott says.
Maple syrup can be a great fuel source and alternate to sports gels during an endurance event, Scott says. It’s a carbohydrate that is mostly sucrose, which is a disaccharide, meaning that it’s made up of two monosaccharides–in this case, glucose and fructose. Research shows that we have limited absorption sites in our intestines for monosaccharides, but multiple sources of monosaccharides are more easily absorbed, Scott says. That makes maple syrup a solid fueling choice before or during exercise. Companies like Endurance Tap and UnTapped sell it in drinkable packets.
Bananas are rich in carbohydrates (about 27 grams per serving) and somewhat low in fiber (3 grams per serving), making them an easily digestible option. “When I have runners that seem to have more sensitive stomachs, we’ll look at bananas,” Scott says. Another plus: They come in their own package, making them a convenient snack to tote with you. For even easier mid-workout fueling, consider baby food pouches with bananas, suggests Scott.
Dates are a portable and quickly digestible snack. Just two Medjool dates have 35 grams of carbohydrates and only 3 grams of fiber, Scott says. Any type of date can be good fuel, but opting for larger-size Medjools means you don’t have to carry as many with you–ideal if you’re eating on the go.