How to Boost the Immune System in Athletes
The immune system is responsible for responding to internal or external stimuli. Fever is an example of an immune reaction in the human body. Before delving into the factors that increase immunity, we’ll clarify some key concepts.
What is the immune system and how does it work?
Organs, tissues, proteins, and special cells make up the immune system. Its function is to protect the human body from germs and microorganisms.
The operation of this system is flawless in most cases. This allows people to maintain the correct condition of health and prevent infections. However, sometimes this system doesn’t work properly and illnesses can occur.
Thyroid diseases or celiac disease belong to a group of diseases known as autoimmune diseases. These occur when the immune system recognizes its own structure as foreign and reacts against them.
Effects of exercise on the body’s immune system
Depending on the intensity of the exercise one carries out, immunity can be modulated. In this way, moderate exercise can improve the capacity of the immune system. However, the effect of intense exercise can be detrimental.
Respiratory conditions, caused by a decrease in immunity, are the main causes of medical consultation in 35–65 percent of athletes. These affect ten percent of athletes during training and competition. Some of the most common causes are stress before the competition or a poor diet.
Nutrition for immunity
Diet and calorific deficit can affect the immune system. This can reduce or even prevent its function.
Furthermore, immunity is also affected by excess macronutrients or poor hydration. This can be when the availability of nutrients is altered—or direct—through hormones.
What factors interfere?
1. Carbohydrates
A correct supply of carbohydrates is very important for the immune system. Eating a fast-absorbing, high-fiber, low-carbohydrate diet increases inflammation. This is the reason why carbohydrate intake in athletes must be properly distributed.
2. Proteins
In this section, we must consider glutamine and protein supplementation. On the one hand, glutamine is an amino acid that performs essential functions in the body.
Although it’s a molecule that occurs naturally, its demand increases as a result of mental and physical stress. For this reason, in overtraining or intense training situations, their requirements are higher.
Taking the above into account, glutamine is often consumed in sports to reduce the risk of infections, as a preventative measure. However, the evidence to support this isn’t very solid and falls within group B of the Australian classification.
On the other hand, protein supplementation can play an important role in the function of the immune system. In this study, it’s been found that high protein intake can reduce respiratory disease in cyclists.
3. Antioxidants
During physical exercise, free radicals can form. In excess, these free radicals can be harmful. To combat them, you can consume foods rich in antioxidants, such as fruit.
4. Other molecules
In this section, we’ll consider beta-glucans and quercetin. Beta-glucans are polysaccharides present in the cell walls of yeasts, fungi, some bacteria, and in barley and rye.
They’re capable of activating cells of the immune system, depending on their molecular weight. Although they’ve shown to be useful in some studies, there’s still little evidence of their effectiveness in humans.
Moreover, there’s a molecule, a polyphenol called quercetin which is present in different vegetables and has been shown to reduce the incidence of respiratory conditions in athletes. However, more quality studies are necessary in this regard.
The immune system and physical activity: summary
If there’s one thing that’s certain about immunity, it’s that an adequate nutritional regimen is necessary so that the immune system doesn’t become compromised.
Moderate training positively impacts immunity. It’s in cases of intense exercise—especially in a situation where training isn’t properly overseen—when the immune system can be negatively affected.
In these situations, optimizing the diet can bring many benefits. For example, the diet of high-performance athletes has to be rich in antioxidant foods, fruits, and vegetables in order to minimize the effects of oxidative stress.
All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.
- Carpenter, K. C., Breslin, W. L., Davidson, T., Adams, A., & McFarlin, B. K. (2013). Baker’s yeast β-glucan supplementation increases monocytes and cytokines post-exercise: implications for infection risk?. British Journal of Nutrition, 109(3), 478-486
- Witard, O. C., Turner, J. E., Jackman, S. R., Kies, A. K., Jeukendrup, A. E., Bosch, J. A., & Tipton, K. D. (2014). High dietary protein restores overreaching induced impairments in leukocyte trafficking and reduces the incidence of upper respiratory tract infection in elite cyclists. Brain, behavior, and immunity, 39, 211-219