Almost every Ironman triathlete has complained of some GI distress at some point. Having to make repeated porta-potty stops from one aid station to the next can make a long day even that much more challenging. Or, listening to the contents of your stomach slosh around for 26.2 miles while your belly swells up like a tick doesn’t make for a great race — or finish-line photo.

One study found that, among Ironman competitors, 93% experienced some type of GI symptom (e.g., acid reflux, gas, bloating, nausea, vomiting) during the race. Among those with GI symptoms, 45% said that their symptoms were severe, and 7% were forced to abandon the race due to their symptoms.

The good news is that most GI problems are avoidable, and proper nutrition training can help ensure that you can race without needing a plumber to clean out your pipes all day. An easy way to minimize the likelihood of having a problem is to practice your race-day nutrition strategies in training, and don’t do anything new just prior to or during your race. If you suffer from GI problems in training, keep a log of the symptoms and what you ate and drank during training — your log can help you identify the culprit(s).

Below are the key culprits behind triathletes’ GI distress and what you can do to best avoid succumbing to your stomach:

Follow a hydration schedule
The stomach and GI tract work best when they have adequate fluids. Being dehydrated can slow stomach emptying, making you feel bloated and giving you the “stomach slosh” effect and other GI symptoms. The key is to keep well-hydrated during the entire race.

By the time you take your first pedal stroke, you are already behind on your hydration, so drink a water-bottle’s worth of sports drink within the first 30 minutes of the bike to help you catch up on your hydration. From that point on, follow the hydration schedule that you developed during training.

Keep concentrated carbs in check
When taking in your carbohydrate calories during the race, make sure to keep them at their optimal concentration. To do that, mix your sports drinks according to labels, and whenever you take an energy bar or gel, be sure to drink the recommended fluid intake with it. If you choose to eat foods, be sure to take 8 fl. oz. (237 mL) of water or sports drink with solids to keep carbohydrate concentration in check.

Sodium and electrolytes
By using higher-sodium sports drinks and gels, you should be able to keep your sodium levels adequate during an Ironman distance race. Most athletes strive for 500 to 1,000 mg of sodium per hour on the bike and run portions of the race. However, too much sodium, potassium, or other electrolytes can lead to bloating, nausea, and vomiting.

Meds for peace of mind
Diarrhea is the most common concern on the run portion of an event, and an anti-diarrheal medicine (e.g., Imodium) can be a great solution and serve as peace of mind. Some athletes who are prone to diarrhea choose to take two Imodium tablets an hour or so before the start of an event and then another two before they begin the run portion, as preventive medicine. They may put the potential remedies in their special-needs bags and on their bikes as added peace of mind.

Some race-day GI problems and solutions:
Problem Solution
Race-day stress, anxiety Choose a liquid meal rather than solid on race morning; use relaxation techniques
Too many calories before and during Stick with tried and true pre-race and race-day fueling strategies; devise a plan, practice in training, and execute on race day
Excess caffeine Practice race-day caffeine intake at “B” races or in training to determine your threshold
High fiber Switch to a low-fiber diet two to three days prior to race day; eat white breads, reduce fruit and vegetable intake, and have more juices and processed low-fiber foods
Too-high intensity Too high an intensity impedes the GI tract from functioning, so you should race at the right intensity; slow down if you are going hard and having GI problems
Aspirin and NSAIDs (e.g., Advil, Aleve, Motrin) Eliminate two to three days prior to race day; only take during race if 100% necessary

About PowerBar Expert Panel
Comprised of leading sports dietitians, researchers, trainers, and sports medicine practitioners, The Panel advises PowerBar on the development of educational programs and materials that relate to sports nutrition and training. They also provide expert perspectives during the Professional Athlete Panels at sport events throughout the country. All of our experts share a passion for sports nutrition and a commitment to helping athletes perform at their best through improved nutrition and hydration.

References
Rehrer NJ, van Kemenade M, Meester W, Brouns F, Saris WH. Gastrointestinal complaints in relation to dietary intake in triathletes. Int J Sport Nutr. 1992 Mar;2(1):48-59

Jeukendrup AE, Jentjens RL, Moseley L. Nutritional considerations in triathlon. Sports Med. 2005;35(2):163-81.

Peters HP, Bos M, Seebregts L, et al. Gastrointestinal symptoms in long-distance runners, cyclists, and triathletes: prevalence, medication, and etiology.Am J Gastroenterol. 1999;Jun;94(6):1570-81.