Microbial Composition (Gut Health) and Exercise – How it works

Exercise can beneficially change gut microbial composition

It is widely known that exercise is not only good for our bodies, but also for our mind. And that regular exercise can prevent various health problems. In recent years scientists and researchers have started to look at the link between regular exercise and gut health. A recent study led by researchers at the University of Illinois show that exercise alone can beneficially change gut microbial composition.

The gut or gastrointestinal tract contains millions of various bacteria that create the gut’s microbial composition and play an important role in our overall health. You probably have heard how fermented foods such as sauerkraut, kimchi etc. or fermented drinks like kombucha and kefir are healthy for your gut as they improve the gut’s microbial composition. New York Times writes:

“This microbiome includes countless different species of microbes in varying proportions that interact, compete and busily release various substances that are implicated in weight control, inflammation, immune responses and many other aspects of health throughout our bodies.”

Now you can add a regular exercise to the list of fermented foods that also improves your gut health.  It has been previously discussed that exercise can possibly alter gut microbial composition. However, as Jeffrey Woods et. al. writes in the recent study from the University of Illinois:

“[previous] studies have not investigated whether the gut microbiota and associated metabolites are modulated by exercise training in humans. We explored the impact of six weeks of endurance exercise on the composition, functional capacity, and metabolic output of the gut microbiota in lean and obese adults with multiple-day dietary controls prior to outcome variable collection.”

This research isolated the effects of exercise from other factors that could possibly influence gut microbial composition or gut flora affirming the role of exercise in determining the composition of our gut flora. To do so, scientists recruited 32 men and women who did not exercise, half of them obese and the rest lean or of normal weight. The researchers then took blood and fecal samples before the subjects started supervised workouts for six weeks. The workouts ranged from 30 minutes of walking and cycling to an hour of running three times a week. During these six weeks the participants were asked to keep to their normal diets. After six weeks the researchers took another round of blood and fecal samples and asked the participants to stop exercising. After another six week, the researchers took another round of samples.

The analysis of these samples showed that the gut flora of the participants changed throughout the experiment, moreover everyone’s gut microbiome responded uniquely to these six weeks of exercise. However, there were also some similarities:

“In particular, they [the researchers] noted widespread increases in certain microbes that can help to produce substances called short-chain fatty acids. These fatty acids are believed to aid in reducing inflammation in the gut and the rest of the body. They also work to fight insulin resistance, a precursor to diabetes, and otherwise bolster our metabolisms.”

The research concludes that:

“exercise training induces compositional and functional changes in the human gut microbiota that are dependent on obesity status, independent of diet and contingent on the sustainment of exercise.”

Furthermore, Dr. Woods argues that theoretically these changes in gut microbiome “could contribute to some of the broader health benefits of exercise, such as its ability to reduce inflammation throughout the body.” More studies need to be done to prove this argument, but it seems clear that regular exercise beneficially changes gut microbial composition in a way that improves immune function, mood and even recovery process post-exercise.

Hope this inspires to keep your exercise goals for 2018, or maybe just start yours now. Remember, keeping it regular is the key. Start by 10 minutes of skipping rope every second day and build it up by adding regular long walks, jogging or swimming. Whatever you choose, stick to it and do it regularly.