Most of you can imagine that a diet rich in fermented foods and dietary fiber is important for nurturing the intestinal microbiome.
But did you know that exercise can also positively affect the intestinal environment?
Recent studies have increasingly shown the relationship between the intestinal environment and exercise.
Today, we at KINS are here to explain the relationship between exercise and the microbiome.
Let's incorporate exercise and practice more effective Microbiome Care for your KINS.
- Moderate exercise creates healthy intestinal microbiota.
- Exercise and constipation
- Relationship between the gut and athletic performance
- 75 minutes a week! The key is a moderate amount of exercise
Moderate exercise creates healthy intestinal microbiota.
Exercise to the extent that feels comfortable gives a sense of relaxation and positively affects the autonomic nervous system.
Since the gut is an organ controlled by the autonomic nervous system, moderate exercise is very important for it as well.
Conversely, however, when exercise causes intense stress or tension, as in the case of athletes, it can bring about stomach problems such as diarrhea or abdominal pain.
This is because excessive stress affects the autonomic nervous system, which in turn adversely affects the function of the intestines.
As you can see, exercise and the intestinal environment have a strong connection and actually affect us in many ways.
Are athletes' gut microbiota more diverse?
Exercise and gut bacteria are not only connected by the autonomic nervous system but also influence each other in a very complex way.
For example, the following is a study on the impact of exercise on the gut microbiome.
In 2014, one study conducted in Ireland noted differences in the diversity of gut bacteria between elite rugby players and healthy people who don't exercise that much. （*1)
This study found;
1) Athletes have a greater diversity of intestinal bacteria than non-athletes (including obese and non-obese).
(2) Athletes have a higher percentage of "good bacteria" in their intestinal environment than non-athletes.
In general, it is desirable to have a diversity of the intestinal microbiome, and an environment with more good bacteria is less likely to cause problems.
In other words, people who do exercise as their life's work are more likely to have a diversity of the intestinal microbiome and maintain a good balance of intestinal environment compared to those who lead a non-exercise lifestyle.
Athletes' intestines have more "weight-loss microbiome"?
Interestingly, the above study also found that those elite rugby players have fewer bacteria of the phylum Bacteroides.
The bacteria of the Phylum Bacteroides are also known as the "weight-loss microbiome" and are said to be abundant in the intestines of people who tend to lose weight.
On the other hand, the study found that an intestinal bacterium called Akkermansia muciniphila, which is known to suppress type 2 diabetes obesity, and obesity are more in those rugby players.
The balance of the intestinal microbiome seems to be closely and intricately related to our body shape and lifestyle-related diseases.
Relationship between the gut and athletic performance
So how does exercise affect the gut microbiome and make it diverse?
The relationship between the human intestinal microbiome and exercise is still in the research stage, and there are still many unresolved aspects.
However, in the case of athletes, aside from high-intensity exercise, their unique dietary adjustments like caloric intake, protein intake, fiber, and carbohydrate intake may positively affect the intestinal environment, too.
In fact, the diets of athletes and non-athletes differ greatly.
In particular, many athletes adjust their intake of carbohydrates and fiber, which affect the balance of the gut microbiome.
One study found that athletes who consumed 25 grams or more of fiber per day had better results in terms of intestinal bacterial diversity. (*2)
And another study shows that the type of exercise and diet also make a difference in the diversity of the gut microbiome.
For example, it has been suggested that endurance athletes, who often consume a low-carbohydrate, low-fiber diet, may experience a negative effect of a high-protein diet on their gut microbiome balance.
In addition, it has been noted that short-chain fatty acid-producing bacteria are less in strength athletes (e.g., bodybuilders), who often consume a high-protein, low-carbohydrate diet.
Short-chain fatty acids produce lactic acid bacterium and Bifidobacterium. KINS users surely know that lactic acid bacterium and Bifidobacterium are our strong allies for our health.
It is not necessarily desirable that the number of bacteria that produce short-chain fatty acids may decrease.
Exercise and constipation
Exercise is also a key for those who suffer from constipation or an upset stomach.
In one human subject study, light exercise has been shown to shorten the time it takes for food to pass through the digestive tract.
A comparison of the gastrointestinal transit time of people who walked 10,000 steps or more per day for two weeks showed that the transit time in the small intestine did not change much, but the transit time in the large intestine was reduced by eight hours.
This means that exercise can prevent the retention of stools.
If you have tried various constipation remedies to no avail, perhaps exercise may be the answer for you.
Relationship between the gut and athletic performance
So far we have discussed the positive effects of exercise on the intestinal environment, and now we would like to look at the effect of the intestinal environment on exercise.
Athletic Performance and Intestinal Environment
Apart from research showing that exercise improves the intestinal environment, recent years have seen research based on the viewpoint that athletic performance may be improved by conditioning the intestinal environment.
It seems that the intestinal environment has become a hot topic in the physical condition of athletes.
In one study on mice, scientists researched the relationship between the intestinal environment and athletic performance, fatigue, muscle mass, etc.
As a result, it has been reported that the pathway by which lactic acid bacterium converts lactic acid to butyric acid increases substances that promote energy production during exercise.
Although the results of human studies are still largely unresolved, the relationship between the intestinal environment and exercise is likely to become even clearer in the future.
75 minutes a week! The key is a moderate amount of exercise
Now we all can see that exercise is very significant in regulating the intestinal microbiome. So, exactly how much exercise should we do?
We at KINS recommend the following two points for exercise to increase the effectiveness of Microbiome Care.
1) Moderate exercise time
2) Moderate intensity
This is because exercise that is too intense could be burdensome.
But I can hear you saying "how much is moderate"?
The World Health Organization (WHO) recommends the following amount of exercise to maintain good health
1) Exercise intense enough to make you sweat: 75 minutes per week.
2) Light exercise such as walking: 150 minutes per week
Walking has been shown to have a positive effect on the gut microbiome.
According to a research report from the University of Colorado in the U.S., adopting an exercise routine such as walking early in life can help maintain a healthier state of intestinal flora. (*3)
Furthermore, it is believed to keep the brain healthy longer and may promote metabolic activity.
Of course, walking is good not only for the intestinal environment, but also for preventing lifestyle-related diseases, weight loss, and beauty.
Aim for about 20 to 30 minutes per day. Relaxing and being conscious of your breathing while walking is the key to getting even better results!
In this article, we have looked at exercise and the intestinal microbiome.
We hope that you now have a concrete understanding of why exercise positively affects our gut health.
Exercise is one of the effective ways to take care of the microbiome to prevent obesity and improve health.
Microbiome Care through diet is essential, but if you incorporate exercise, you can even further enhance the effectiveness.
The important thing here is to take up exercise to the extent that it does not cause stress.
Take it in gradually at your own pace!
・（※1）The Irish rugby team has exceptional guts: Exercise and diet impact gut microbial diversity
・（※2）The Effect of Athletes’ Probiotic Intake May Depend on Protein and Dietary Fiber Intake
Joy Son, Lae-Guen Jang, Byung-Yong Kim, Sunghee Lee, and Hyon Park
・（※3）Early-life exercise alters gut microbes, promotes healthy brain and metabolism
University of Colorado at Boulder
・Exercise Modifies the Gut Microbiota with Positive Health Effects
Vincenzo Monda, Ines Villano, Antonietta Messina, Anna Valenzano, Teresa Esposito, Fiorenzo Moscatelli, Andrea Viggiano, Giuseppe Cibelli, Sergio Chieffi, Marcellino Monda, Giovanni Messina
・Lactobacillus plantarum TWK10 Supplementation Improves Exercise Performance and Increases Muscle Mass in Mice
Yi-Ming Chen, Li Wei, Yen-Shuo Chiu, Yi-Ju Hsu, Tsung-Yu Tsai, Ming-Fu Wang, Chi-Chang Huang
・Early-life exercise may promote lasting brain and metabolic health through gut bacterial metabolites
Agnieszka Mika, Monika Fleshner