There are times when the body reacts to the hectic and strenuous activity you put on it. This is the point where the body has undergone an ‘immune crash’. During that time when you train in greater volume, intensity or heaviness above an optimal point of body functions, it is very likely that your immune system might fail you. For example, this ‘immune crash’ majorly faces recreational or professional athletes and others whose focus is always on becoming more powerful, quicker and stronger. How can you prevent immune failure and illnesses during active workout sessions? Basically, evidence from epidemiology and anecdote have established that the best way to avoid the ‘immune crash’ is by moderating your training and making it as regular as possible. Positive effects on your immune system have positive effects of reducing any illnesses in your body. By improving your immune system you will stand a better chance to be healthy.

In this article, we are going to speculate what happens to the body during intense training periods. We are also going to dig deeper to lymphocyte production up from the impairment of natural killer cells. We shall examine further on supplements and the science power that can help.

Study Reviews

Conducted Studies and their Findings

  1. First Study

A study done in Australia at the University of Queensland (Department of Human Studies) had found out that intensive exercise had changed immune factors such as circulating leucocytes (leucocytes are known for protecting the body against pathogenic diseases). The aim of this study was to determine the effects of exercise intensity on parameters of immune to understand better the mechanisms through which training can influence infection resistance.

Further findings showed that the concentrations of plasma cytokine were steeply affected. Cytokines are secretions that carry signals from one cell to another. They aid greatly to the development and functioning of immune responses (both adaptive and innate). If they get altered, they respond in turn by altering immune system ‘communication’.

  • Second Study

Scientists from Spain (Athletic Club of Bilbao), based at Basque, examined the hormonal markers such as cortisol and testosterone among other objectives. They found out that the changes overtraining had caused could not correlate with changes in capacity of athlete’s performance. Further, overtraining could create a hormonal environment allowing pathogens to increase and thrive. The reason for these findings is because both the epinephrine and cortisol suppress the production of T-cell cytokine.

The general effect of these impairment is that an athlete will develop sore throats and flu like symptoms as more as is experienced commonly by the general population. These common colds may take quite a longer time to heal while it hampers athlete’s training and performance.

The Study on Upper Respiratory Tract Infection (URTI)

The URTI is a very common infection found among athletes. It is caused by an infection that spreads on the upper respiratory tract (these organs include the larynx, pharynx, nose and sinuses). Most studies have examined the URTI on objectives such as evaluation of the effects of intense and prolonged exercise on incidence of the population’s infection. However, this study has received a couple of criticism for not addressing factors such as allergies, air pollutants and airway inflammation among others. The researchers of Australia (University of Queensland) had to step up this study to cover symptomatology and pathogenic etiology of the URTI among the highly trained elite athletes, untrained sedentary control group and recreationally competitive athletes.

Being conducted over five months ago during competitions at summer and autumn, this study collected throat and nasopharyngeal swabs on a two or more defined URTI symptoms subjects. These swabs were then analyzed using culture, microscopy and polymerase chain reaction for a viral, bacterial, mycoplasmal and chlamydial respiratory pathogens.


According to their findings, 37 of the URTI episodes were reported amongst 28 subjects. The sedentary control group had 9 victims, recreationally competitive athletes recorded 7 victims while elite athletes group had 21 people victimized. On infectious agents’ factor, the study had recorded only 11 people victimized; 2 of the sedentary control group, 3 of the recreationally competitive athletes and 6 of the elite athletes. While, there were 26 episodes with no pathogens of URTI. There were further high scores for total symptoms, specific symptoms and functional impairment in subjects with infectious URTI. The study claimed that URTI among the elite athletes was seldom infectious, and distinct symptomology between infectious and noninfectious was evidenced. It recommended for a future research to be done on noninfectious causes of URTI, consideration and investigation on identification of alternative mechanisms and the mediators. But this study supported the fact that moderate regular training have the ability to reduce the infections risks through the positive effect of immune system.

It is determined that most people prone to this URTI are sedentary and elite individuals because of suppressed immune system. You can avoid URTI, the featured ‘immune crash’. The J-shaped model is basically supported here because it indicates how the intensity of exercise affects immune health. This J-shaped model suggests that just a moderate exercise lowers the respiratory infection risks as excessive exercise will increase this risk.

How to prevent URTI

If you want to prevent URTI, prepare a scheduled or a well-designed training regime. We say, ‘better prevent than to cure a disease’. The result of any serious athlete pushing himself or herself to the absolute limit is failure of the immune system. This fact is made known to them first-hand. It doesn’t matter how well-designed the routine is.

On this high note point, studies refer athletes and sportspeople to supplements of help.

The supplementation

More athletes are supplementing their bodies with antioxidant supplements such as vitamin E and Vitamin C. Montmorency cherry tart extract was found as a better antioxidant by many studies because it has the ability to enhance quick recovery by minimizing oxidative stress. This recently, most sportspeople have been using this as a supplement for the reasons provided by studies.

The Carbohydrates Role

Researchers from the Immunology Centre (Loma Linda University Medical Centre, California) had found out that consuming carbohydrates during an exercise or workout tends to improve increases in catecholamines, plasma IL-6, ACTH, and cortisol. Consuming approximately 30-60 grams of carbohydrate per hour while on a 2 ½ hours strenuous exercise had led to the suppression of IFN-?-production and decrease of percentage of IFN-?-positive T lymphocytes. This result was observed on a trial of placebo control. IFN-?-positive, being a cytokine, is vital for adaptive and innate immunity against the intracellular bacterial and viral infections.

Carbohydrates supplements improves the efficiency of the immune system as you go on an excess training at a high intensity and even toward the J-shaped higher end.

Supplementing by the BCAA Factor

Sports nutritionists have specifically recommended branched chain amino acid (BCAA) as a supplement for those on overtraining practices and who experience immune system suppression.

The connection between the BCAA supplementation and immune response was determined in a study by evaluating few blood parameters e.g. level of plasma cytokines, plasma glutamine concentration etc. It was found that after an intense exercise, a decrease in the concentration of plasma glutamine had paralleled by an increased symptoms of infections incidence. Further finding showed that BCAA supplementation could reverse the reduction in the concentration of serum glutamine. This was after prolonged and intense exercise as per the observation made.


Most trainers have overlooked immune system on their overtraining mode. But if they understand how immune systems and how they work, they have a guaranteed way of staying healthy and keep progressing with their lifts without illnesses drawbacks.