The Importance of Gut Health on Training Performance

The Importance of Gut Health on Training Performance


While I do personally pay close attention (well… most of the time) to the dietary side of training, it is something I rarely write about in depth.  This, for the most part, is due to be my preference (and passion) being further on the training side of the spectrum than the dietary side of the spectrum.

But despite that, I do think that providing good quality dietary advice is essential to both assisting people on an individual basis, and trying to break through the misinformation that (unfortunately) runs rampant within the online health and fitness industry.

This is s why I got quite excited when the guys over at Nutrishatives offered to write a guest post on the importance of gut health on training performance - an opportunity I obviously jumped at.

With that in mind, the following guest post will be looking at how the health of our gut can impact our ability to train, and the effectiveness of that training.

So let's get to it.


The Importance of Gut Health  on Training Performance

Many of us who have an interest in our physical fitness, often also pay close attention to our diet.  With this comes an understanding of what food we should and shouldn't eat (well, most of the time), how much of each macronutrient we need to consume, often coupled with a basic understanding of nutrient timing.

But something that is less frequently discussed within the training world is gut health, and how it can impact our ability to train and recover.

Interestingly, there has been a host of recent research to suggest that (while what we eat is indeed important) the health of our gut and digestive system may actually have an even greater impact on our continued improvement than diet alone.

With this in mind, having a healthy gut can greatly impact our ability to train and recover effectively through three primary mechanisms:

  • Improve the ability to absorb nutrients from the food we eat, leading to much more efficient recovery processes.
  • Boost the function of the immune system, ensuring that we can train on a consistent basis without any interruption.
  • Maintain optimum hormone levels, leading to improved appetite regulation and energy usage (and ultimately making us leaner as a result).
hunter bennett perfomance gut health


The Microbiome

The human gut contains approximately 2kg (around 4 pounds) of bacteria at any one time.  Individually, these bacteria are known as micriobiota, while the many microbiota found in the gut are collectively described as the microbiome

The bacteria that make up the microbiome can simply be described as either good bacteria or bad bacteria. Taking this into consideration, good bacteria essentially promote the healthy function of the gut, while bad bacteria impede it. 

Interestingly, maintaining healthy gut function can have a positive impact on many of the body's other physiological systems, including both the cardiovascular system and the immune system.

As such, having adequate good bacteria within the gut can pay huge dividends when it comes to our performance and training based goals.


Gut Health Improves Our Recovery

Good gut bacteria have been shown to produce enzymes that breakdown complex carbohydrates and proteins into smaller molecules (glucose and amino acids, respectively).  These smaller molecules are much more readily absorbed into the body than their much larger counterparts, and can therefore be used immediately in many of the body’s essential processes.

From an exercise perspective, this means that having a healthy gut can greatly speed up the body's ability to absorb and shuttle both amino acids and glucose molecules to the muscle tissue.  This greatly enhances the body's ability to repair damaged muscle tissue and replenish glycogen stores, both of which are essential to efficient recovery.


Gut Health Can Stop Us Getting Sick

Many don't realize that in conjunction with their impact on the digestive processes, bacteria of the gut also act as one of the body's most integral lines of defense.  The food we eat often contains trace amounts of harmful bacteria (something that, unfortunately, cannot be avoided).  If left to its own devices, this bacteria can physically damage the intestinal lining of the digestive system, causing it to become porous (leading to a condition known as leaky gut)

In this scenario, foreign and undigested matter transfer easily across the intestinal wall and into the bloodstream.  This leads to potential infection and illness, combined with a substantial increase in systemic inflammation.  Both of these factors also lead to a huge drop in immune system function.

This can greatly impact our ability to train effectively, and can also inhibit our ability to recover from our training sessions.

But fortunately for us, good gut bacteria actually have the capacity to stave off foreign matter and harmful bacteria through two primary mechanisms.  Firstly, good bacteria of the gut physically consumes the same essential nutrients bad bacteria need to survive.  In doing so, it essentially starves the bad bacteria within the gut, causing its death.

Secondly, the good bacteria within the gut can break down fiber from the food we eat (a type of carbohydrate that is somewhat unusable to the human body) into short chain fatty acids (SCFAs).  These SCFAs (being a type of acid) actually increase the acidity of the gut to a level that makes it extremely difficult for infectious bacteria to survive.  In doing so it limits their ability to function, and over time, leads to death.

As a result, having adequate good bacteria within the gut can greatly reduce the amount of foreign matter entering the body.  This can lead to improved immune system function, and a reduction in inflammation.  As a direct result, we can now train consistently without the risk of ailments derailing our success.

Gut Health  Can Keep Us Leaner

In conjunction with their influence on bad bacteria within the gut, SFCAs are also absorbed into the body through the digestive system.  Once in the body, these SCFAs are known to interact with specific receptors within the cells of the body (known as 'G-protein coupled receptors') causing the secretion of the hormone leptin.

Leptin plays an important role regulating appetite, and has also been shown to improve insulin sensitivity within the human body.  Through the interaction of these two key factors, the body becomes more competent at using fat and glucose for energy, and we also experience significantly reduced hunger cravings.  As a result, our ability to lose fat mass is greatly increased, as is our ability to keep it off in the long run.


Practical Applications

Considering the broad impact that gut health  can have on our ability to train and recover, it quickly becomes apparent that we should do what we can to maintain adequate levels of good bacteria within our digestive system. 

With this in mind, the following tips provide simple ways you can improve the state of your digestive system, and greatly improve the results of your training.

  • Limit your intake of processed foods: Highly processed foods have been shown to impact our ability to absorb nutrients within the gut, and can even cause inflammation within the digestive system.  This can impede the action of good bacteria, limiting our ability to fight infection and absorb nutrients.

  • Eat Probiotic Rich Foods: Probiotic rich foods are essentially those foods that have undergone a process of fermentation.  Fermented food contain specific compounds that feed the good bacteria within the gut, improving their health and function.  These foods include and kimchi, kefir, sauerkraut, and natural yogurt, and can easily included into the diet on a daily basis to cause huge improvement in gut health.

  • Boost your intake of fiber: Good bacteria feed off of dietary fiber.  As such, by consuming more fiber we can increase its health while simultaneously increasing the production of SCFAs (as discussed above).  By consuming fibrous vegetables with each meal is a great way to maintain optimal bacterial balance within the gut, and improve digestive health.


Maintaining a healthy gut can improve both our ability to train on a consistent basis and recover from our workouts.  As a result, it is essential to maximizing our performance (and our results) in the long term.

Fortunately for us, improving gut health doesn't have to be a challenge.  By simply making some small and smart changes to our diet, we can see huge improvement in the state of our gut.  And of course, if you have had any experiences with gut health, we would love to hear about them, so please drop us a comment and we will get back to you ASAP.



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