Bacteria in the gut not only protect us from obesity and allergies, they also make us more efficient. The microbiome has a lot to offer, especially for endurance athletes. Tips to keep it healthy and to achieve top performance in sports.

Microbiome research has recently ventured into the areas of fitness, leisure and competitive sports, which have so far been little studied. Rightly so, because the fitness of athletes depends on many factors, for which bacteria in the intestine are at least partially responsible.

In order to perform, athletes need sufficient energy and nutrients. The body must be able to protect itself from sports-related inflammation and free radicals and to regenerate quickly after exertion.

Michaela Axt-Gadermann is a doctor and professor for health promotion in the “Integrative Health Promotion” course at Coburg University. She lives with her husband and children near Fulda. She has written numerous books on the subject of “intestines” and developed a licensed online nutrition coaching program (“Healthy with Intestines”) that is recognized by health insurance companies. You can also find more information on the “Slim with intestines” website.

Researchers have now found that the microbiome actually improves fitness and that gut bacteria are a coach, training partner and physiotherapist all in one. It is now assumed that the intestinal flora is responsible for at least 20 percent of physical performance. Above all, a species-rich, diverse flora seems to have a beneficial effect on the cardiovascular system, immune system and energy supply.

If you consider that many sports are about seconds or minutes and that even recreational athletes find it more fun if the training session is easier, then the condition of the intestinal flora may be an important concept for success for athletes and fitness athletes who are willing to perform.

“Healthy with intestines” by Michaela Axt-Gadermann

The research team led by Jonathan Scheiman from Harvard Medical School in Boston was able to demonstrate how closely the composition of the microbiome is linked to endurance. The scientists collected stool samples from runners before and after the Boston Marathon and compared them with people who did not take part in the run.

It was noticeable that bacteria with the beautiful name Veillonella could only be detected in large numbers in the participants after the marathon, but not in the comparison group with predominantly sedentary activities. In order to clarify whether the multiplication of the microorganisms was only a result of exertion or whether the bacteria can actually affect performance, the Harvard scientists then transferred the sports chair to laboratory mice.

The rodents now had to work themselves out in the hamster wheel until they were exhausted. And indeed: Veillonella doping significantly increased the performance of the rodents. They lasted longer and ran 13 percent further than the mice without bacterial support. How do the bacteria do it? Veillonella do not use glucose or fructose as an energy source, but metabolize lactate, i.e. lactic acid.

Lactate is produced during physical exertion and is considered a performance-limiting factor, because it makes the legs of endurance athletes feel heavy and the muscles tired. But the more lactate accumulates, the easier it is for Veillonella to multiply. And they not only eliminate the performance-inhibiting lactate, they actually convert it into the performance-enhancing propionate.

Propionate is one of the short-chain fatty acids that are formed by the microbiome. Similar changes have now also been demonstrated in other endurance athletes such as rowers or ultra-long-distance runners. Athletes and Veillonella therefore have a “symbiotic” relationship: the higher lactic acid content in the intestines of athletes favors the growth of Veillonella and these bacteria in turn produce propionic acid, further improving athletic performance. By the way: Certain dietary fibers (see below) also stimulate the formation of the performance-enhancing fatty acid propionate.

Butyrate (butyric acid) is another short-chain fatty acid that is formed in the intestines through the bacterial breakdown of so-called “prebiotics”. Prebiotics are plant fibers that we humans cannot digest, but which are converted into valuable fatty acids by microorganisms. Butyrate provides energy, modulates the immune system, has anti-inflammatory properties and obviously improves fitness as well.

Canadian scientists from the University of British Columbia, Kelowna, analyzed the microbiome of 39 subjects with different levels of exercise and found that the microbiome of the fit not only had a greater biodiversity than that of the less trained, but also harbored significantly more bacteria that butyric acid ( butyrate) can form.

However, diversity and sufficient butyrate-forming bacteria are not important for young or middle-aged athletes. Seniors also benefit from a healthy intestinal flora, but lose their fitness and become increasingly frail if the microbiome becomes monotonous – for example due to nutrient-poor home food.

As early as 2005, connections between declining physical and mental performance could be linked to typical changes in the microbiome. If there was a lack of butyrate-forming bacteria such as Faecalbacterium prausnitzii and lactic acid bacteria (lactobacilli) in the intestines of the elderly and if the number of microorganisms that promote inflammation increased, then the frailty of the pensioners also increased significantly. Meanwhile, numerous other studies also confirm that aging or decline in fitness and vitality are closely related to changes in the microbiome and loss of biodiversity in the gut

The studies mentioned suggest that a well-established intestinal flora could give athletes a decisive advantage. Experiments on animals and studies with athletes have examined in more detail whether performance can also be specifically improved by taking probiotic bacteria.

The lactic acid bacterium Lactobacillus plantarum has many great properties. One of them is turning skinny mice into muscular dudes. For six weeks they received a daily dose that would correspond to around 10 billion germs in humans. This improved the strength in the paws – in humans this would be called grip strength.

In addition, the mice had significantly more endurance and parameters that indicate muscle fatigue (lactic acid, muscle enzymes) increased less than in the mouse group that received a placebo. Body composition after six weeks showed that the rodents with L. plantarum had become fitter and stronger: they had lost weight and their body fat percentage was lower. At the same time, a significant increase in muscle mass was observed.

Excitingly, legal performance enhancement not only works in mice, but also in humans. Australian scientist Cecilia M. Shing heads a working group at the University of Tasmania, Australia, which is investigating legal options for improving athletic performance. The effects of probiotic bacteria are also examined more closely.

To do this, long-distance runners first had to undergo a performance test under extreme conditions. You should run on the treadmill at 35 degrees Celsius and 40 percent humidity until exhaustion. The athletes were then randomly assigned to either the placebo group or the group receiving probiotic bacteria (Streptococcus thermophilus, lactobacilli, bifidobacteria).

After four weeks, a second test was carried out under the same conditions. While the placebo group threw in the towel after an average of 33 minutes, the athletes strengthened with probiotic bacteria lasted almost 5 minutes longer (37:44 min). Such an improvement in performance within just four weeks is enormous – anyone who trains regularly can judge that.

Probiotics can also be useful for muscle training. If strength athletes took the probiotic bacteria Streptococcus thermophilus and Bifidobacterium breve for three weeks, the regeneration time was reduced and training-related inflammation decreased. No effects on the muscles could be detected in the placebo group.

tinier andere Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus plantarum, Lactobacillus yeast, Lactobacillus acidophilus, Lactobazillus helveticus, Bifidobacterium longum, andBifidobacterium lactis, Bifidobacterium breve, Bifidobacterium bifidum, Streptococcus thermophilus

A healthy microbiome is beneficial for athletes in several ways. Performance-oriented athletes often weaken their immune system through hard training. By administering probiotic bacteria, the duration and frequency of infections in athletes and recreational athletes can be reduced and the immune system strengthened.

Active athletes also produce many free radicals. These aggressive molecules are created in our metabolism every day, but are also encouraged by our lifestyle. Physical stress increases the formation of these pollutants. Protection is provided by antioxidants from food, but also by the body’s own enzymes, which can scavenge free radicals.

Italian scientists have now discovered that the intestinal flora also contributes to the antioxidant protective layer. To do this, they divided 24 athletes into two groups. One received an ineffective placebo, the others received the lactic acid bacteria Lactobacillus paracasei and Lactobacillus rhamnosus daily.

The athletes completed a tough training program for four weeks. Blood samples were taken at the beginning and end of the study. The result showed – this is common knowledge in sports medicine – that the oxidative stress increased during the training, i.e. the organism produced more free radicals. However, taking probiotics also increased the antioxidant protective capacity in the blood, neutralizing free radicals before they could cause damage.

The conclusion of the authors: Athletes and everyone who is exposed to oxidative stress can benefit from probiotics.

Studies have shown that probiotics can be beneficial for athletes because they

According to current knowledge, the microbiome and performance are closely linked. Although there is certainly still a need for research, it can already be said with certainty that a healthy, diverse microbiome has a positive influence on performance at any age. Probiotic bacteria (ideally combined with prebiotic fiber) also likely have the potential to promote fitness. A sufficiently long and correspondingly high-dose intake is important.