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Challenging weather conditions, tight muscles, and mental roadblocks are obstacles routinely confronted when readying to hit the trail. Preparation is the key to success. To avoid setbacks, runners purchase proper clothing, perform stretches, and create the perfect mix of motivating music.
Despite best efforts, unanticipated curveballs can bubble to the surface. A pesky problem that no runner can escape is flatulence. The rumble in the jungle experienced hours after a hearty meal can be an annoying, painful experience that brings even the fittest runner to their knees.
Food nourishes bodies and fuels exercise. The right ingredients can be the perfect catalyst to break a personal best. However, the gastrointestinal tract is a confusing system. It is continuously active, and when the wrong food is eaten at the wrong time the gas produced can be excruciating.
Sometimes the solution is simple, like avoiding excessive carbon dioxide from carbonated beverages, or slowing down when eating to reduce the amount of air swallowed. However, other times gas is produced as food material travels from the small intestine into the large intestine. This semi-liquid mass of partly digested lunch is known as chyme. When it arrives, the carbohydrates and fiber it contains prompt the gut to start working. This process results in the production of nitrogen, oxygen, hydrogen, carbon dioxide, and methane.
Dietary proteins are not necessarily in the clear either. Like certain offending vegetables, meats, nuts, legumes and eggs contain sulfur. Bacteria in the gut tackle the sulfur as well, reducing it to a product known as hydrogen sulfide. This detectable gas gives flatulence its disturbing, and often memorable, stench.
Each person has a unique digestive environment, so what makes one runner gassy may pass through another runner without complication. Learning to navigate the loops and twists of an intestine is no easy task, and quite honestly is still a mystery to even the most knowledgeable gastroenterologists. Thankfully, research has provided guidance.
Foods With High Fiber
First to consider are foods with high amounts of dietary fiber. Fiber is the substance that gives food its structure. It is resistant to human digestive juices, meaning once it enters the digestive tract it doesn’t get absorbed but instead continues down the chute. It is extremely beneficial for health, this cannot be said enough, but is also know to cause stomach upset while pounding the pavement.
There are two types of fiber: soluble and insoluble. Soluble fiber is the main cause of the aforementioned fermentation, and has a viscous (think sticky) texture while making its way through the digestive tract. Most foods have a mixture of both fibers, but foods with a substantial amount of the soluble kind include legumes, oats, Brussels sprouts, citrus fruits, flaxseed, and psyllium husk.
Insoluble fiber is roughage that helps form the bulk of stool. Add adequate fluid and physical activity to the mix and regular bowel movements will make constipation the least of your worries. Of course, there is a time and place for this, and mid-run is not one of them. Insoluble fiber can also trap oxygen as it is digested, resulting in painful gas that takes time to be released. Foods high in insoluble fiber include wheat bran, seeds, nuts, leafy greens, and the skins of fruits and vegetables.
Foods High In Sulfur
The next potential offender is a food high in sulfur. Though vital for health and often described as a natural healer, too much sulfur can wreak—er, reek—havoc on a runner’s stride. Foods to be weary of include cruciferous vegetables (broccoli, Brussels sprouts, cabbage and kale), protein-rich foods (poultry, fish, meats, nuts, legumes, and eggs), and allium vegetables (onions, garlic, leeks and chives).
Needless to say, the overall list is exhausting. Runners are presented with a conundrum: how to fit these nutritious foods into a diet without compromising performance. As the saying goes, timing is everything.
Although every body differs (so know thy self), on average it takes six to eights hours for food to pass through the stomach and small intestine, and then find its way to the large intestine. To put this into perspective, a snack of an apple and almonds around 10:00am typically will reach the large intestine at approximately 4:00pm to 6:00pm. If a schedule carves the best time for a run to be after work, this may mean trouble. Instead, have the fruit and nuts earlier with breakfast or save them for dinner after. If it is preferred to jog early in the morning, be careful of late night snacks that fall on the list.
Another thing to consider is portion. A single piece of fruit or a handful of seeds eaten hours before exercise may not pose a problem, but a large bowl of barley topped with broccoli and onions could mean gas overload.
Not all foods should be feared. If an extra boost of energy is needed, here are a few safe bet snacks that are still nutritious:
- Banana with 1 Tbsp natural peanut butter
- 6 to 8 ounce smoothie, preferably with fresh vegetables and fruits and minimal-to-no added sugars
- 3 ounce cooked fish or chicken with ½ cup cooked brown rice
- Half an avocado (about ¼ cup) spread over 1 slice sourdough toast
It should be mentioned that there are chronic conditions that require more specific dietary guidelines. Individuals with a disease of the digestive tract, such as Crohn’s, ulcerative colitis, lactose-intolerance, Celiac, and gastro-esophageal reflux should seek the advice of a Registered Dietitian. For example, a diet gaining credibility for treatment of Irritable Bowel Syndrome is known as low-FODMAP (Fermentable Oligosacchrides, Disaccharides, Monosacchrides and Polyols), which encourages reduction and/or avoidance of these shorter-chain carbohydrates that are hard to digest.
Otherwise, go ahead and enjoy these healthful foods, but before you do, consider that a gut works equally as hard as muscles propelling a run. To avoid bloat, show a little courtesy and give it time to clean up after a meal.