Physical activity keeps you a lean, mean fighting machine. It also keeps your gut bacteria whipped into good shape, too. The benefits of exercise for gut health include the production of gut-healing short-chain fatty acids (SCFAs) and metabolites, a more diverse microbial composition to prevent bacterial overgrowth, and prevent weight gain because…well, who doesn’t like a trim bod? Let’s discuss the connection between exercise and the human gut microbiome!
What Is the Gut Microbiome?
The gut microbiota is the collective microbial community housed within the lumen (the space inside the tubular structure) of our intestinal tract. There is a growing body of evidence on the capability of microorganisms within our gut microbiome to respond to dietary, environmental, pathological, and genetic factors.
The gastrointestinal (GI) microbiome represents a complex network of trillions of microbes, mainly consisting of bacteria. Gut microbes coordinate in a bidirectional way to affect our general state of health.
The effect of diet and potential therapies (prebiotics and probiotics), in improving gut health, have been extensively studied. Recently, the role of environmental factors, such as exercise training, is also being understood to affect our gut microbiota profile .
A relatively recent cultural, behavioral, and dietary shift alongside the availability of calorie-rich food, has led to the development of an obesogenic (obesity) lifestyle in humans. Let’s talk about why you should consider increasing your level of physical activity to improve your gut health.
Exercise and Human Gut Microbiome
Exercise interventions are an excellent way to biohack your gut health. Combining physical activity with proper diet and strain-specific probiotic supplementation will help boost microbial diversity in your gut. With a wider spectrum of bacteria, you will have better digestive health, meet your weight loss goals, and boost your mood. Let’s discuss the positive impact of exercise on the gut microbiome.
Better Overall Health
Exercise has been widely recognized as a useful therapy for a range of diseases, including:
• Cardiovascular Disease
• Systemic Inflammation
The processes through which exercise can have a therapeutic effect on human diseases have been extensively studied and found to be many and also interconnected. In this article, we will try to focus on the role of exercise in the lens of changes in gut microbiota, the effect of exercise on our gut microbiota composition, and the therapeutic benefits of exercise in transforming the characteristics of the human gut microbiota.
Most of your immune system cells reside in your gut. They help modulate inflammation along the gut barrier. When we endure chronic inflammation, it compromises our gut bacteria, immune system, and overall health and wellbeing.
Studies show that exercise helps improve your immune system naturally . Physical activity burns fat, promotes metabolite-producing bacterial growth, and lowers stress. All of these benefits reduce inflammation and ultimately, the development of many chronic illnesses.
Obesity is ranked as the most prevalent preventable health-related disease globally. Current estimates suggest that there are approximately 1.9 billion obese humans worldwide . That doesn’t count those who are considered overweight. These numbers have tripled since the 1970s!
Obesity is understood to be a multifactorial disease resulting from interconnected factors such as social, environmental, physiological, neural, and genetic components. The gastrointestinal tract symbolizes the primary interface between our health and the consumed nutrients.
Traditionally, research has suggested that obese humans tend to have a microbial imbalance that favors Firmicutes to Bacteroidetes . However, new studies have emerged indicating that this discrepancy might not be the biomarker for obesity.
Now, scientists have tied a lack of Faecalibacterium prausnitzii and Akkermansia as markers for gut dysbiosis . Inversely, the host becomes more susceptible to inflammation and weight gain.
Researchers also noted that those with weight issues might have elevated levels of Proteobacteria. This finding further cements the importance of bacterial diversity.
Improves Bacterial Diversity
In this study, mice were made to undergo endurance exercise and had their gut microbiomes compared to sedentary counterparts. The goal was to see if physical activity increased alpha diversity within their microbiota. Researchers observed a change in over two thousand bacterial taxa!
Research has already established the role of gut microbiota in the regulation of metabolism in skeletal muscle. In mice, exercise has been demonstrated to increase the prevalence of the Lactobacillus species and decrease bacteria from the Tenericutes phylum within the microbiota .
Multiple studies have shown that exercise induces an increase in microbial diversity, which is one of the signs of a healthy gut both in animals and humans. In one of the few studies which involved humans, athletic rugby players and healthy controls were compared based on their microbiota composition. Athletes showed more than twice as many phyla, genera, and families of bacteria compared to their non-athletic counterparts .
Prevents Leaky Gut and IBS
Another study involving humans noted that physically active people tend to have more taxa, such as:
These probiotic bacteria are known to produce a significant amount of butyrate . Butyrate is a beneficial short-chain fatty acid that helps repair the gut lining. It has strong anti-inflammatory effects to prevent the degradation of the intestinal lining that might cause Leaky Gut Syndrome or Irritable Bowel Syndrome (IBS).
Plus, this metabolite promotes apoptosis. Apoptosis caused sick and potentially cancerous cells to degrade so that healthier cells can be formed instead.
Another recent study noted that endurance exercise also promotes the production of acetate , especially in the large intestine (colon). Exercise expedites this process by encouraging fermentation of large intestine bacteria, which in turn, produces this beneficial short-chain fatty acid.
Acetate is the most prevalent SCFAs in the body. It is essential for metabolizing lipids, cholesterol, proteins, and amino acids.
Exercise has been shown to counteract the alterations in the gut microbiota caused by a high-fat diet. Moreover, evidence suggests that early life exercise can influence the gut microbiota composition stimulating the development of bacteria that are capable of determining our metabolic profile . Early life exercise might help in the optimal development of brain function and in promoting health-enhancing microbial guests in our gut.
Exercise stimulates our vagus nerve. This series of nerves serve as a communication line between our gut bacteria and brain. When specific bacteria take over the system, it disrupts homeostasis. Ultimately, the vagus nerve picks up on the problems and it alters hormone production to influence our mood.
Exercise creates new diversity. It helps break up the dominance of one particular bacterial species that might be overstaying its welcome and causing you mental health issues.
Lactococcus lactis and Lactobacillus plantarum and two Lactobacilli strains under the Firmicutes phylum. They are known to activate 5-hydroxytryptamine receptors (5HT) . This physiological process is the precursor to serotonin production. Serotonin is an important neurotransmitter that regulates so many crucial functions, including our sleep-wake cycle, appetite, and overall mood.
There is enough literature to confirm the therapeutic role of exercise in promoting good health. The mechanisms by which the gut microbiota influences our energy, metabolism, and satiety are being studied extensively and researchers have established the unique relationship of exercise in shaping our microbiome independent of the diet. Thus, exercise alters the gut microbial population quantitatively and qualitatively which benefits the host aka us.
As we mentioned earlier, exercise also boosts the presence of butyrate-producing bacteria. Studies suggest that butyrate also influences serotonin production .
Exercise and Human Gut Microbiome Side Effects
Now, we shouldn’t be sedentary women and men. However, there is too much of a good thing. Too much exercise can cause wear and tear on the body and negatively impact the gut biome. Plus, it might cause injury or hyperextension when you overexert.
Additionally, excessive exercise can cause stress. In turn, too much endurance training or high-intensity exercises can exacerbate GI problems, including IBS. Don’t push yourself too hard every day. Break up your exercise routine with lighter workouts, including walking or yoga.
Exercise for Good Gut Health
Exercise leads to the enrichment of microflora diversity, contributing to reducing weight, obesity, and gastrointestinal disorders. Working out promotes the proliferation of gut bacteria which can influence our mucosal immunity and improve barrier function, which can help in the reduction of metabolic diseases and obesity.
Exercise also helps in stimulating the growth of bacteria which is capable of producing substances that protect us against colon cancer and gastrointestinal diseases. So, now you know how your gym routine, or your morning jog, or the many other forms of exercises, are interconnected with the concept of human health in terms of your gut. Get moving!
Want to see how diverse exercise is making your gut? Get your gut tested with Thryve. We’ll let you know which bacteria you need, which are too abundant, and the foods you need to balance your microbiome!
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