Why a healthy gut plays an essential role in athletic success

Whether you’re a professional athlete or just enjoy exercising and an active lifestyle, setbacks caused by a weakened immune system are never a pleasant surprise. This is, however, not uncommon amongst athletes. While moderate exercise is beneficial and makes your immune system more resilient, research shows that heavy exercise can suppress the immune system, hence increasing the risk for infections and fatigue. The good news is that a healthy and balanced gut flora can strengthen your immune system and improve not only your athletic performance but your overall health as well.  

Heavy exercise can suppress the immune system 

A strong immune system is important for athletic performance. The immune system helps you to recover quicker after an intense workout and protects your body from infections and harmful bacteria. But while moderate exercise has a positive impact on the immune system, more intense physical activity – especially endurance related – will temporarily suppress your immune system and make your body more vulnerable to bacteria and infections. After running a marathon, the immune system can be suppressed for as long as 72 hours. This is why it’s especially important for athletes to strengthen their immune system.  

80 % of our immune system resides in the gut 

Researchers have found that people with a physically active lifestyle have a more varied and balanced gut flora. At the same time – a healthy gut flora leads the way to a strong immune system, which is a key component in successful athletic performance. Our gut is home to millions of good bacteria working to help our bodies regulate blood sugar levels, encourage emotional balance, support digestion and strengthen our immune function. In fact, 80 % of our immune system is situated in the gut. A healthy gut flora with both a large number and wide range of good bacteria benefits our health in many ways. A balanced gut flora keeps the bloodstream free of toxins and harmful microbes, reduces the number of harmful bacteria, increases antibody levels, produces antimicrobial molecules, lowers pH levels and regulates signaling pathways in immune and intestinal cells.  

Studies show a connection between probiotics, the immune system and athletic performance 

Many studies have been made on the benefits probiotics can have for athletes. Probiotics do not only strengthen the immune system, but also help our bodies to maintain energy and endurance levels, support bone and muscle health, reduce bloating, gas and cramps, and support healthy antioxidant levels that protect us from oxidative stress by neutralizing free radicals. 

A study published in International Journal of Sport Nutrition and Exercise Metabolism looked at eighty-four people who were highly active during the months of winter training. One group was given a probiotic supplement and the other a placebo. The results showed that the placebo group had a significantly higher number of upper respiratory problems and were 36 % more likely to experience issues for over a week’s time. Also, the group that were given the probiotic supplements showed higher levels of an important antibody called salivary lgA, which is one of the body’s first lines of immune defense.  

In another study focusing on athletes who had over trained and were showing signs of fatigue and impaired athletic performance, researchers found evidence of T-cell damage. T-cells are an active and important part of the body’s immune response. After a month of adding a daily probiotic supplement to their diet, the athletes’ T-cell activity returned to healthy levels again. 

When studying professional rugby players, researchers found that the rugby players who were given a daily probiotic supplement showed a reduced incidence and duration of upper respiratory health issues. In fact, the rugby players who were given a daily probiotic supplement during a four-week period were more than twice as likely to stay healthy than the players given a placebo. The rugby players taking the probiotic supplement who did experience upper respiratory issues also recovered faster.  

Strengthen your immune system by probiotics and a healthy lifestyle 

Taking care of your gut health and maintaining a balanced gut microbiome is important for a strong immune system. This is important not only for the quality and quantity of your training, but for your overall health as well. Here are some tips on what you can do to keep both you and your gut happy and healthy: 

  • Strengthen your gut flora with a probiotic supplement. 
  • Embrace a plant-based diet high in prebiotics to maintain a balanced gut. 
  • Try to avoid medications, especially antibiotics, that obliterate the good bacteria.   
  • Expose your body to healthy microorganisms by spending time outside in nature.  



Gleeson, M., Bishop, N. C., Oliveira, M., & Tauler, P. (2011). Daily Probiotic’s (Lactobacillus caseiShirota) Reduction of Infection Incidence in Athletes. International Journal of Sport Nutrition and Exercise Metabolism,21(1), 55-64. doi:10.1123/ijsnem.21.1.55 

Shephard, R. (2007). Reversal in fatigued athletes of a defect in interferon γ secretion after administration of Lactobacillus acidophilus. Yearbook of Sports Medicine, 2007, 136-138. doi:10.1016/s0162-0908(08)70120-x 

Haywood, B. A., Black, K. E., Baker, D., Mcgarvey, J., Healey, P., & Brown, R. C. (2014). Probiotic supplementation reduces the duration and incidence of infections but not severity in elite rugby union players. Journal of Science and Medicine in Sport,17(4), 356-360. doi:10.1016/j.jsams.2013.08.004 

Shing, C. M., Peake, J. M., Lim, C. L., Briskey, D., Walsh, N. P., Fortes, M. B., . . . Vitetta, L. (2013). Effects of probiotics supplementation on gastrointestinal permeability, inflammation and exercise performance in the heat. European Journal of Applied Physiology, 114(1), 93-103 

Parvaneh, K., Jamaluddin, R., Karimi, G., & Erfani, R. (2014). Effect of Probiotics Supplementation on Bone Mineral Content and Bone Mass Density. The Scientific World Journal, 2014, 1-6 

Martarelli, D., Verdenelli, M. C., Scuri, S., Cocchioni, M., Silvi, S., Cecchini, C., & Pompei, P. (2011). Effect of a Probiotic Intake on Oxidant and Antioxidant Parameters in Plasma of Athletes During Intense Exercise Training. Current Microbiology, 62(6), 1689-1696.  




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