Understanding Digestion and Running
Running gives your bowels a little bit of a shake and a squeeze, affecting your intestines. It’s a great cure for constipation. However, if you have a normal healthy set of bowels, this movement might mean you need to go for a poo.
Tips for Managing Bowel Movements While Running
There are a few tips that might help if you’re struggling with this during your runs. Self-experimentation is key to understanding the impact of different variables on you. When preparing for a run, especially a longer one, try to avoid other factors that might speed up the transit of food through your bowels.
Diet Adjustments Before Running
Fibre Intake: High fibre foods are great for digestion but also speed up digestive transit. Consider cutting down on fibre the day before and the morning of a long run.
Fat Content and Spiciness: Be mindful of the fat content and spiciness of the foods you eat before running. High fat and spicy foods can affect your digestion significantly.
Food Volume: Avoid eating more than usual. The idea of loading up on pasta or other foods before a run might not be beneficial, as a higher food volume can increase the need for bowel movements.
The Benefits of Keeping a Digestive Diary
Keeping a diary about what you eat and its impact on your digestion can be helpful. Note how your stomach reacts and the effects on your bowels, particularly for the food you’ve eaten earlier.
Anecdotal Evidence and Practical Advice
A runner I spoke to was experiencing frequent bowel movements during her long runs. We eventually realised it was because she was eating dates and prunes as her long run fuel, which are known to relieve constipation symptoms. This combination sped up her digestive process.
Encouragement for Open Discussion Among Runners
It’s essential to talk about these issues, like needing to go to the loo, wild peeing, or needing a poo on a long run in an awkward place. These are topics we should discuss as runners because they impact our training.
Conclusion
Keep these tips in mind for your next run. Remember, it’s about finding what works best for your body and running style. Happy Running!
The video above is Coach Alexa’s advice. The section below is an expanded written guide from Team We Run, added to include extra context, FAQs and practical examples.
How To Stop Needing A Poo Mid-Run (Runner’s Trots, Triggers & A Simple Plan)
Runner’s trots is usually a timing + triggers problem: eat lower fibre/fat the day before, leave 2–4 hours after meals, avoid caffeine/fuels that set you off, and practise the same pre-run routine until it’s predictable. Needing to poop during a run is most often caused by gut “jostling”, stress hormones, and what’s still sitting in your bowel from the last 12–24 hours.
Why running can trigger the urge to poop
Even if your digestion is normally fine, running can increase gut motility and urgency. The impact/jostling of running, a rise in stress hormones, and changes in blood flow can speed things up – and whatever you ate in the last 12–24 hours can be the final piece of the puzzle. That’s why some runners get a mild “need to go”, while others get cramps, diarrhoea when running, or full-on GI distress during long runs.
For many people, the big ones are: caffeine, high-fibre foods (bran, big salads, beans/lentils), high-fat meals, dried fruit (dates/prunes), very concentrated gels/drinks, sugar alcohols (some bars/chews), and sometimes dairy.
The 24-hour plan (best for long runs)
The day before
- Go lower-fibre than usual (especially if you’re prone to runner’s trots).
- Keep meals simple: familiar foods, fewer “wildcards”.
- Avoid heavy/high-fat and very spicy meals if they’re a known trigger for you.
The morning of the run
- Keep breakfast smaller and easier to digest.
- Lower fat, lower fibre tends to work better than “super healthy” high-fibre choices.
- If you’re unsure, choose simple carbs you know you tolerate.
The 2–6 hour window (where most mistakes happen)
- Avoid big meals close to running (especially high fat).
- If caffeine makes you urgent, reduce or delay it until after the run.
- Hydrate steadily rather than chugging a load right before you leave.
- If you wear tight kit around your waist, try loosening it for long runs.
What to eat (and what to avoid) before long runs
If you’re trying to reduce the urge to poop when jogging or running, food choice matters – but tolerance is individual. Use these as starting points and adjust based on what your gut handles well.
Usually safer options (for many runners)
- White rice or plain pasta
- Toast with a little honey/jam
- Banana
- Plain bagel
- Small bowl of porridge (if you tolerate it)
- Small yogurt (only if dairy doesn’t trigger you)
Often riskier (especially close to running)
- Big salads, bran cereals, lots of raw veg
- Beans/lentils and very high-fibre meals
- Lots of nuts/seeds (especially right before a run)
- High-fat foods (pastries, fried foods, heavy creamy meals)
- Very spicy meals (if you’re prone)
- Dried fruit (dates/prunes) and foods with sugar alcohols
Fuel is a common culprit (especially “healthy” options)
Mid-run urgency (including pooping during a run) is often caused by what you’re using for fuel. Dried fruit like dates and prunes can speed things up for many people. Some gels, sweets, and sports drinks can also be problematic – especially if your gut isn’t used to them, or if they’re very concentrated.
Don’t introduce new fuel on race day. Practise your exact long-run/race routine in training and keep it boring.
Nerves make it worse (and it’s common)
If it’s mainly happening before hard sessions or races, it may be as much about anticipation anxiety as food. Stress can ramp up gut activity fast – even if you ate “perfectly”. A consistent warm-up, leaving extra time, and sticking to a familiar routine can reduce the panic-urgency loop.
A simple runner gut diary (takes 30 seconds)
- What you ate the day before
- What you ate 2–4 hours before
- What you took during the run (gels/drinks/snacks)
- What happened (urgency / cramps / diarrhoea / fine)
You’ll usually spot patterns quickly – and once you know your top trigger, it becomes much easier to manage your bowel movement before running and reduce surprise urgency.
Common panic moves to avoid
- Eating more than usual the night before “to fuel up”.
- Suddenly adding lots of fibre (bran, big salads, loads of fruit) right before long runs.
- Trying new gels/drinks/supplements close to a key session or race.
Example routine (copy/paste and tweak)
If you run at 9:00am, try this for 2–3 long runs and adjust based on your diary:
- 7:00pm (night before): simple, lower-fibre dinner (e.g., rice/pasta + a familiar protein).
- 6:00am: small breakfast (e.g., toast + honey, or a plain bagel, or a banana).
- 6:00–8:30am: sip water steadily (don’t chug at the last minute).
- 8:15–8:45am: easy warm-up + bathroom opportunity.
- During the run: only use fuel you’ve tolerated before (and keep concentration sensible).
FAQ
Why do I always need to poo when I start running?
Why is it worse on long runs?
Should I cut fibre before a race?
Are gels a common cause of runner’s trots?
When should I get it checked?
A practical plan for your next long run
24 hours before: reduce fibre and keep meals simple (avoid known triggers). 2–4 hours before: keep food smaller, lower fat, and predictable. Caffeine: reduce or delay if it triggers urgency. During: only use fuel you’ve tolerated before. After: jot down what happened so you can spot patterns and refine your routine.
