Whether it's 5k or a marathon, bloating can hit runners hard - as well as bowel movements...
But why do our bodies sometimes react to exercise like this, and why is running so much worse?
It's quite common for runners to experience "Runners Diarrhoea" - in fact, it's so common, it's been studied! A published study done on 109 long-distance athletes was done around their bowel movements.
Sixty-two percent (62%!) reported that they had to stop to go to the loo in training. While 43% said that they have nervous diarrhoea before a race and 51% said they have experienced it after a race.
This is isn't just found in elite athletes, but people of all abilities. In another study, it showed that 90% of participants had some sort of gastrointestinal issue are endurance races like the London Marathon - including bloating.
Wild Dose founder, Charles Instone, mentioned "Remember, this is on healthy people - 10-15% of people have IBS in the UK. So for some, this can hit pretty suddenly during a run and they are much more likely to struggle with a stomach issue while on a run."
So what is it about long runs that cause a disproportionate amount of tummy issues for, what are widely considered, fit and healthy people?
A Long Story
Long story short, there's a mix of factors as to why this might happen. "Physical exercise acts as a modulator of the gut environment" leading Gut Health Specialist and Nutritionist, Marilia Chamon, says. "Due to demands of skeletal muscle. Strenuous exercise such as long distance running leads to less blood flow to the digestive system which can promote symptoms."
Firstly, with bloating after a run - it's likely that you might suffer from it for three reasons.
1. Water Retention
As you run, you'll release cortisol as a response to the stress which increased blood pressure as well as increasing the production of glucose which you need for energy. This is great but in extreme levels - like running long distance - it can also cause water retention which can make you look bloated or puffy.
2. Swallowing Air
This results in a gassy bloat as you can swallow air when you run, over 5-10k that might not be that much but over a marathon that can really add up. This results in lots of gas in your digestive tract that is struggling to escape. That's when you might need a little gas relief.
3. Undigested Food
If you eat during a long run, which many do via high energy snacks - you could eat too quickly or end up with undigested food in your digestive tract. This undigested food is feasted on by bacteria which release gas, filling you up with a gas filled tum. On top of that, while you exercise, blood flows to your muscles and not your gut - this means your gut won't contract as regularly and might struggle to move the gas out of the body.
Beat the Bloat to the Finish Line
While bloating or runners tum might happen, you can reduce your odds of it matching your pace with a few clever lifestyle preparations. Here's a list of Marila Chamon's top recommendations, based on leading nutritional evidence, for stopping the bloat impacting your PB:
- Stick to safe foods: this is not the time to experiment - stick to the nutritional habits you put in place while practicing for the long distance event to avoid surprises.
- Time your food: avoid eating a big meal 2-4 hours before the event.
- Reduce stress levels: the gut and the brain are intrinsically connected and stress can contribute to a faster gut transit. Consider doing some deep breathing exercises pre-race.
- Stay away from gut irritants: caffeine, alcohol, spicy, fried and fatty foods.
- Check ingredients: if you have a sensitive tummy watch out for high FODMAP ingredients that can be found in gels and energy drinks such as: agave syrup, inulin, chicory root, apple/pear juice concentrate, xylitol, isomalt, erythritol, fructooligosaccharides (FOS)
- Avoid any "gas producing" foods - Brussels, broccoli, beans, the main culprits of a windy tum.
- If you snack during the marathon, stop for it. This will be easier on your tum and also stop you from swallowing air.
- Hydrate, yep the ol' classic of "drink some water" is out to fix literally everything. Seriously though, taking on regular water before, during and after will help you more than you can imagine.
- Snack on bananas, these have a great balance of minerals to keep your digestion ticking over and stop water retention (also very good for period cramps!)