The rundown on runner’s trots
Thanks to children’s author Taro Gomi, as toddlers we learned that everyone poops.
That’s certainly true for runners, even (and especially) when we’d rather not — like midway through a long run, or two miles into a big race.
There is no show-stopper quite like having to go on the run.
Running certainly seems to exasperate GI issues, and “runner’s trots” is a phrase for a reason.
In fact, MultiCare Sports and Wellness Dietitian Lisa Lovejoy says that anywhere between 20–80 percent of runners experience some sort of GI distress (nausea, gas, cramping, diarrhea) during or immediately following running.
Lovejoy explains that while the cause isn’t really known, the issue is attributed to a few things:
1. Jostling nature of running: Your insides slosh around a bit with the repeated impact of running, making this issue much more common in runners than swimmers or cyclists.
2. Fast pass: Exercise/training increases motility of foods through the GI tract, reducing the time between consumption and elimination. The plus side of this may be one reason runners have a lower incidence of cancer.
3. Body function prioritization: Blood shunting toward working muscles during exercise, and thus away from the GI tract.
4. Bad timing: Poorly timed eating or drinking habits are an especially known irritant.
5. Race day jitters: Nerves and the associated hormonal responses affect the GI system — your adrenaline is pumping, and if your body is reading this as a fight or flight moment, your body wants to pare down to the essentials. Bye, poop.
6. Fueling on the run: The use of sports nutritionals, especially goos, gels and bars. Their high sugar concentration (by design) can draw water into the gut and cause GI upset. This can be reduced by consuming plenty of water alongside these items to help dilute the sugar load.
7. Dehydration: Just makes everything worse!
8. Unrelated: Undiagnosed lactose intolerance or irritable bowel disease (IBD).
Some causes can’t be avoided, such as a jostling stomach, but Lovejoy did explain some key ways to prevent an episode:
1. Respect the two-hour window: The general rule is no solids two hours before a run, but find what works for you. Keep it simple and avoid foods that are loaded with sugar or hard to digest.
2. Keep it calm: Reduce/eliminate the consumption of “stimulants” the day before a race. These include caffeine (responses vary individually, so experiment with this); spicy, gassy, high-fat foods; and, for susceptible individuals, dairy foods. Artificial sweeteners, especially sugar alcohols (sorbitol, mannitol, xylitol) and fiber additives (inulin or chicory root, common in many energy bars) may contribute to diarrhea at any time, especially with the added stress of exercise.
3. Pass on fiber: While fiber is usually considered to be part of a healthy diet, reducing it the day before an event may help reduce GI distress.
4. Gel well: If you do use sports nutritionals, be sure to drink plenty of plain water along with them (as above) and train with them. Don’t try anything new on race day!
5. Build slow: Gradually increasing training distance or intensity should also help give your gut time to adapt to your new habits.
Some of the above are sweeping best practices, but of course there are individual exceptions. I would add that practice makes perfect. Practice using the same breakfast before every long run, practice using gel during a workout and see how your body responds.
Lovejoy is “a big fan of using food records to identify trends” and suggests including your fuel notes alongside your training journal, including what you ate, when and how it made you feel. You’ll start to identify patterns for yourself.
Of course sometimes you’ll do everything “right” and still end up cramping mid-run and looking for the nearest bathroom (or tree). The best way to make it the next pit stop in an emergency is to walk — it can really calm your stomach down.
And if you find that it’s constantly happening around the same mile point, plan your loop accordingly. Luckily, Lovejoy says, “most runners feel significantly better after voiding and can return to their run.”
GI issues on the run happen to everyone at some point. If you bring up poop with a group of runners, everyone has a horrifying (and hilarious) story to tell.
In the moment, it’s awful, but there’s no shame. Welcome to the runners’ club!
This article was originally published June 2017 and updated May 2018.
About The Author
Sarah Robinson is a runner, mom, brand storyteller and writer living and training in Tacoma. She has been running and racing for over 20 years and was a 2016 Olympic Trials qualifier in the marathon with a PR of 2:42:36. She has raced and won Sound to Narrows once, and remembers it as one of the toughest (and most fun) courses she’s raced.More stories by this author