If you’re like most runners, you have at some point experienced mid-run stomach trouble that forced you to cut short a workout or even a race. So what’s going on? When you run, your body diverts oxygen and blood from your gastrointestinal (GI) tract to your muscles. This limits your stomach’s ability to do its job, sending improperly digested food into your intestines, drawing fluids with it and setting the stage for GI problems. High-intensity runs, long runs, warmer weather and dehydration all exacerbate this effect. But there are steps you can take to help minimise these troubles.

1. Side stitch

      Gripping pain in the upper GI area affects about 25 per cent of runners. The pain is probably caused by reduced blood flow, as well as ligament stress.

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      2. Heartburn

      common runner GI issues and how to fix them.

      The bigger the meal, the more time you need to completely digest it before you start running: Avoid your trigger foods. Don’t lie down after a pre-run meal. During your warm-up, avoid core work, such as sit-ups, as it may aggravate heartburn.

      3. Burps and wind

      Caused by gas-forming foods. Nerves, which can make you swallow air, don’t help.

      common runner GI issues and how to fix them: Avoid foods that cause gas. A pre-race meditation routine will calm your nerves and limit stress hormones that restrict GI blood flow.

      4. Mid-run nausea and vomiting

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      common runner GI issues and how to fix them: common runner GI issues and how to fix them.

      5. Mid-run diarrhoea

      Caused by a combination of running and restricted GI blood flow. Race-day nerves can stimulate the bowel, making matters worse.

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      6. Post-run fever or diarrhoea

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      How to fix post-run stomach issues: Reduce training intensity for a few months, then slowly build it up again. Stay hydrated.

      What else could be causing your running GI issues?

      Practise a pre-race calming routine.

      1. Pain relievers

      Anti-inflammatories such as ibuprofen and naproxen can irritate an already inflamed gut and may lead to more damage.

      2. High-fibre foods

      Fibre promotes bowel movements. Skip high-fibre veggies, fruits and packaged foods a day or two pre-race.

      3. Big pre-run meals

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      4. High-sugar drinks

      Sports drinks, non-diet fizzy drinks and fruit juice can load your gut with sugar, which can aggravate bloating and diarrhoea.