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We’ve all been there. One minute we’re gliding effortlessly down the trail; the next, we are doubled over, looking for a place to bury toilet paper. The gut can make or break a workout or race performance, and, for many runners, it is their worst nightmare.
Stomach issues can be more complicated, and there are a number of things that affect that all-important organ while on a run. Discomfort could indicate a stress response caused by running itself, genetics, food intake, fluid and electrolytes, or an underlying issue such as a food sensitivity or allergy.
From the moment that we start our run, our insides get jostled around and blood is diverted away from the digestive system to power moving muscles. Our bodies also produce stress and inflammatory hormones. That combination can lead to the symptoms we dread most: cramping, bloating, diarrhea, gas, acid reflux and vomiting. Here’s how to beat those gut issues.
Train the Gut
You can train the gut to handle a certain nutrition plan … to an extent. Because digestion is slowed when running, practice makes perfect before and during your run. The day and hours before a big effort is not the time to eat a big spicy meal or to hit high-fiber goals. Keep your snacks simple—lower fat, a small amount of protein and low fiber. White rice, white bread, bananas, honey and jam are good choices.
Timing is equally important. For extra-sensitive stomachs, eat at least two to three hours before exercise to ensure the gut’s heavy lifting is done before the workout. A simple carb snack or sports drink can be used to top off the carbohydrate needs an hour before.
Which Mid-Run Fuel Is Best?
Choose products that maximize your uptake of carbohydrates during activity. Go for snacks that mix carbohydrate sources: glucose, fructose and sucrose. Running-store shelves are stocked to bursting with a plethora of different gels, chews and bars.
Ultimately, it’s up to the individual and takes a little trial and error to know what works best. There aren’t hard-and-fast rules, but these gentle guidelines will help you steer clear of a mid-run disaster: easily digestible carbohydrates with a small amount of protein and little to no fat tend to work best. Some athletes can tolerate real-food options like boiled potatoes or rice cakes, but many runners prefer the portability of liquid and pre-packaged options.
Some runners sweat a little; some a lot. Everyone’s sweat contains a different mix of electrolytes, salts and minerals. Combine that with varying temperatures for training and racing, and things get complicated. It can be really difficult, and even dangerous to dig yourself out of a dehydration hole.
Generally, shooting for a daily intake that’s around half your body weight in ounces of fluid is enough for most. For those logging extra miles, add in 16 to 20 ounces per hour of activity. Finding a hydration mix that works well with your body is important to replace lost fluids and electrolytes, and helps fuel your working muscles.
Absent other culprits, your digestive woes could stem from a food sensitivity. FODMAPs are a group of short-chain carbohydrates that are resistant to digestion and can produce gas and diarrhea for sensitive individuals, and can be particularly problematic for runners. Dairy, wheat, onions, garlic and finish-line-favorite watermelon all contain FODMAPs.
Most people are not sensitive to all FODMAP foods, and an elimination diet sans guidance can leave you with elevated stress and nutrient deficiencies. Consult a professional if you’re looking to pinpoint food-group triggers in your diet.
A Few More GI Solutions
1. Try Tums: Popping a peppermint Tums mid-run can neutralize acid in the stomach and prevent acid reflux or vomiting.
2. Soothe with Ginger: Ginger chews, gels or hydration mixes can ease nausea and help settle the stomach.
3. Balance Electrolytes: Neglecting to replace the electrolytes (like sodium, potassium, chloride, magnesium and calcium) lost through sweating can lead to stomach cramping and nausea. Most sports-drink mixes contain some electrolytes, or try adding some BASE salts, a Nuun tablet or mineral drops to your water.
4. Keep a Journal: Track your symptoms and nutrition plan as part of your training log and race report, which can help you pinpoint and avoid causes of GI distress.