beetroot juice

The Performance-Enhancing Gut


Preparation involves more than having top of the line gear. If you’re going to be the best you need to optimize every element of your training. What you put in your body serves as the foundation for your performance. Probiotics reinforce that foundation ensuring you are ready to go on game day.

The 4 Keys to the Performance-Enhancing Gut:

1. Improved immune function: Athletes are more susceptible to impaired immune function, and subsequent illness, due to the shear amount and intensity of their training and competition. Probiotics can prevent illness in athletes in  several ways:

Physical barrier - L. fermentum and L. plantarum have been shown to increase the production of mucin, which is a substance produced in the gut that inhibits the bad bacteria from attaching to the intestinal wall. Lactobacillus and Bifidobacterium have also been shown to reduce GI permeability (“leaky gut”) which occurs during times of intense exercise and heat and can lead to impaired immune function and poor recovery as well. 

Cellular changes - probiotics stimulate anti-inflammatory proteins. 

Systemic immunity -  probiotics can increase the number and activity of cells that fight off infection.

2. Maintenance of optimal glucose levels

The gut microbiota ferments complex carbohydrates into short chain fatty acids (butyrate, acetate, and propionate). The type and amount of SCFAs produced depends on our age, diet (e.g., availability of prebiotics), composition of gut microbiota, gut transit time and pH of the colon. The probiotic bacteria that produce SCFAs include:

  • Bifidobacterium
  • Lactobacillus
  • Faecalibacterium
  • Ruminococcus
  • Bacteroides

The SCFAs, propionate and acetate serve as fuel sources for the liver and muscle tissue, allowing for the maintenance of optimal glucose levels to meet the body’s demands during exercise. 

3. Reduce inflammation thereby reducing fatigue

Probiotics can reduce inflammation in several ways. One mechanism was evaluated in a study performed with runners taking a probiotic with Lactobacillus and Bifidobacterium strains. The researchers found the runners had reduced inflammatory markers following running in heat. In turn, these runners were able to run longer in the heat without becoming fatigued. 

Another mechanism that has been studied involves the fact that intense exercise generates a high amount of reactive oxygen species (ROS) (i.e., free radicals), especially during exhaustive and long-lasting exercise. Subsequently, the intense exercise and increased oxygen consumption (which also leads to oxidative stress) results in athletes with greater amounts of ROS circulating in their body. 

Probiotics can fight ROS by stimulating antioxidant activity, which can facilitate better recovery from oxidative stress. In turn, it would appear that probiotics, through their antioxidant activity, have the ability to augment recovery from intense exercise. 

4. Nutrient production and absorption

Various bacterial strains improve our nutrition status by aiding digestion, enhancing absorption and synthesizing nutrients. Certain probiotics can:

  • Synthesize some B vitamins and vitamin K
  • Increase absorption of calcium, iron and vitamin D 
  • Enhance dietary nitrate conversion to the vasodilator nitric oxide (e.g., beetroot juice)

By enhancing nutrient production and absorption, probiotics are important players that bring together nutrition, gut health and human performance. 

The gut is as vital to your performance as any other organ system. Whether it is reducing GI symptoms or improving nutrient production and absorption, taking care of your gut with proper nutrition and probiotics will ensure your best on game day. 


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West,N.P., Pyne,D., Peake,J.M., Cripps, A.W.  Probiotics, immunity and exercise: a review. Probiotics, immunity and exercise pp 107-126

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Beet Boosting Bugs

Are you drinking your beets?

You have likely heard about the performance-enhancing superfood, beetroot. Or maybe you have already incorporated it into your training. Either way, it’s hard to ignore the growing attention paid to beetroot. But how does this dark red root improve your 10k time and are there ways to get more out of your glass of beetroot juice?

The mechanism behind beetroot’s boost lies in nitrates. Nitrates are a chemical compound found in beetroot as well as dark, leafy vegetables. When we ingest nitrates they get converted into nitric oxide (NO). Our bodies use NO in a variety of ways, but NO is the link between beetroot and improved performance.

Jason Houston at BeetBoost explains it like this: 

NO relaxes the muscles by widening blood vessels when it spreads through underlying muscle cells in the arterial walls. This affects how efficiently cells use oxygen — efficient oxygen use is a very good thing — and this is one of the reasons why beetroot juice can be used to support sport performance. 

For an excellent, and more detailed look at this process read InsideTracker’s article .

In order for this process to occur, it turns out that our bodies need a little help from the bugs inside us to get the performance boosting benefits from nitrate. The bacteria in our gastrointestinal tract play a huge role in NO production – from our oral cavity to our colon. The name of this system is a mouthful (pun intended): the entero-salivary nitrate-nitrite-NO pathway. The nitrate in foods like beetroot get broken down by bacteria in the mouth, stomach and small intestine and eventually converted to NO.

We know that bacteria play a pivotal role in NO production throughout the entire gastrointestinal tract based off several studies. In one such study, researchers eradicated the bacteria of the mouth using mouthwash. This effectively destroyed the bacteria in the mouth that help convert the nitrate to NO. Subsequently, they found that NO levels were reduced and the benefits of the nitrate were lost. The take home message here is go easy on the Listerine!

Also, studies have shown that germ-free mice (no bacteria in the gut) do not effectively produce NO. Furthermore, rats supplemented with lactobacilli probiotics in conjunction with a nitrate load resulted in a 3-8 fold NO increase in the small intestine. It is studies like these that have lead researchers to believe that our microbiome plays a key role in the production of NO from dietary nitrate. In fact, it has been theorized that some of the beneficial effects of probiotics might be mediated through NO. 

The studies are fascinating, but inevitably lead to more questions: What is the optimal beetroot/nitrate dose? Would particular probiotic strains plus beetroot, augment the production of NO more than the beetroot alone? Are microbiomes of various dietary patterns more conducive to NO production?

What we do know is this: beetroot improves select performance parameters via NO, and our microbiome plays an integral part in the production of NO. More studies will lead to even better insights, but it is obvious that if you want more out of your beets and sports nutrition, it pays to take care of your gut.