Running and Your Gut: More Closely Connected Than You Think

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Running and your gut: More closely connected than you think. Running and Your Gut: More Closely Connected Than You Think

The old saying that you can’t outrun a bad diet might be truer than you think. While for many runners this simply means that you can’t optimally perform on a diet of junk food and sugary treats, it actually goes much deeper than that. Because the bacteria living in your gut is intricately involved in how you feel and perform every day. Intrigued? Here’s how it all fits together.

Gut Biology 101

Did you know that your body plays host to approximately 3.8·1013 individuals of bacteria from more than 1000 different species? Which, in the 70 kg “reference man”, weighs around 0.2 kg? The human gut houses the vast majority of these bacteria, and the composition of each person’s gut microbiota is as unique as a fingerprint. And although your own, personal microbiota is established early in life, it changes over time. Such changes are usually caused by ageing, diet, geographical location, drugs and/or supplementation.

And while the fact that you carry around thousands and thousands of organisms within your body may seem eerie, it’s in your own best interest to keep your gut microbiome in tip-top shape. But why? Well, in addition to playing a key role in digestive health, your microbiota also influences your immune system, mental well-being and body weight, to name but a few.

Ways in which a healthy gut can positively impact on running performance

A healthy gut can also benefit your running performance in various ways, including the following:

  • By supporting and contributing to a healthy immune system. Your gut microbes, in particular, play a vital role in regulating your immune function. It therefore comes as no surprise that a healthy and diverse population of gut microbes help to prevent common upper respiratory- and gastrointestinal illnesses. Which, in turn, translates to fewer sick days and more consistent training.
  • By boosting natural energy levels and endurance. Beneficial bacteria in your gut produces enzymes and aids digestion, thereby helping you to maximally absorb nutrients from your food. Some bacteria even produce short-chain fatty acids that are used by your body as additional energy source. Which, in short, means that your body can keep on going for longer without the help of additional energy sources like gels and energy drinks.
  • By counteracting some of the negative side-effects of (intensive) running. Struggling with gastrointestinal issues like bloating, cramps or diarrhea on the run? A healthy, balanced gut microbiome may help prevent these issues.

  • By reducing recovery time. Beneficial gut microbes help thwart inflammation by regulating your immune system and producing short-chain fatty acids. Which translates to quicker recovery times and less agony!
  • By promoting strong bones and joints. Healthy gut bacteria can produce vitamins and enzymes that are vital to mineral absorption and the metabolism of calcium within the body. This, in turn, can lead to stronger bones and joints and less injuries.
  • By contributing to mental and emotional well-being. A number of brain chemicals and hormones, including serotonin and cortisol, are either produced or modulated by gut bacteria. A healthy gut can therefore play a vital role in both your mental and emotional well-being.
  • By aiding quality sleep. Through the regulation of certain neurotransmitters, beneficial gut microbes can contribute to a good night’s rest. And we all know by now that enough, good quality rest is a vital part of any training regime.

A word of caution

And while this certainly is great news for runners, it should be noted that too much running can also have a detrimental effect on gut health. A recent article published in Alimentary Pharmacology & Therapeutics summarized the findings of gut health studies conducted over the past 20 years and concluded that too much exercise can “compromise gut integrity and function”. It was found that, in general, gut problems manifested after two or more hours of exercise at 60% or more of an individual’s maximum intensity level. Events such as 160 km ultra-marathons and Ironman triathlons showed the largest incidence of participants exhibiting gastrointestinal problems. The study did, however, also identify a number of prevention and management strategies that could potentially reduce this effect.

The study team recommends that individuals exhibiting signs of gut disturbances during exercise undergo a full gut assessment to get to the root of the issue.

How to contribute to the health of your gut

So what else can we as runners do to ensure a healthy, happy gut microbiome? Here are a few simple, yet effective tips:

  • Run! Good news for runners is that a 2014 study published in Gut found that physical activity appears to have a beneficial impact on gut microbiota diversity. The reasons for this are complex, but appear to be linked to the fact that active individuals tend to follow healthier, higher-protein diets. Remember, though, that too much exercise may be detrimental!
  • Eat a variety of different foods. In today’s hurried world many of us fall into a food rut, rotating a handful of dishes week in and week out. Experts warn that by doing this, we could be missing out on foods that are vital to a flourishing mibrobiome. Try branching out your diet and include a wider variety of wholesome, nutritious foods.
  • Avoid overly-processed, sugar-laden and artificially sweetened foods. These foods quell beneficial bacteria and may cause unhealthy microbes to flourish.
  • Make probiotic food sources a part of your daily diet. Fermented foods such as sauerkraut, kefir and kombucha are rich in probiotics and can make a positive contribution to a healthy gut microbiota.
  • Nourish your beneficial microbes with prebiotics. Prebiotics are foods that are rich in indigestible fibers, the latter which act as food source to beneficial gut microbes. Ingesting a variety of whole, plant-based foods such as oats, bananas, garlic and onions, will ensure that your microbiota is nourished and happy.

  • Take a good probiotic supplement. Look for a multi-strain, high-quality formula that delivers bacteria deep into the gut.
  • Mind your lifestyle choices. A number of aspects of a modern lifestyle can negatively impact on the health and diversity of your gut microbiome. Watch out for the following culprits: Stress, some medications, antibiotics, chlorinated water, anti-bacterial cleaning agents and over-eager hygiene habits.

The takeaway

So if you’re still trying to outrun a bad diet, why not stop and give your gut microbes a little TLC? You’ve got nothing to lose, right? And, who knows, you might even catapult your running performance to a whole new level in the process!


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