What Does Exercise Immunology Mean For Us?
- 3 mins read
- Written by: Dr. Pramod Mane
If you are a beginner in exercising, you might have enthusiastically read about different terms related to exercise- aerobic exercise, dancercise, flexibility exercise, thermogenesis, etc. But have you come across the term exercise immunology? For most of us, the term may be new, because this field is indeed relatively new!
We all exercise and try to be physically active, as we all understand the significant role of physical exercise in improving our immunity. But did you know that the effects of exercise on immunity vary with intensity? This is where the newly emerging research term called “exercise immunology” comes into the picture! Wondering what this new term is? Let us understand a little more about what exactly exercise immunology is and what it means to us.
What is exercise immunology?
In simple terms, exercise immunology is a research area which deals with the short-term and long-term effects of different intensities and workloads of exercise on the immune system.
Exercise workloads have direct impact on the immune system!
Studies have shown that short bursts of moderate intensity exercises positively impact the cells of the immune system. On the contrary, high intensity exercises, especially in athletes, have shown to damage the mucosal immunity. Mucosal immunity refers to the protection provided by the layer of mucosal membrane on the respiratory tract that acts as a barrier to the pathogens, and protects the respiratory system from infections. Damage to this mucosal immunity due to high exercise workload and stress can increase the risk of upper respiratory tract infections. However, additional factors such as climatic changes, nutritional deficiencies, anxiety, loss of sleep etc may also contribute to impaired immune response in athletes.
Impact of short bouts of
of moderate-intensity exercises, such as brisk-walking, dancing, gardening, etc. play an important role in the number and function of immune cells. They improve the primary defence mechanism which includes immunoglobulins, neutrophils, Natural Killer (NK) cells, cytotoxic T-cells and macrophages. Short bouts of moderate-intensity exercises also prevent high levels of stress which may impair the cellular functions of the immune system.
Impact of prolonged
A number of studies have suggested that high-intensity training (running, fast swimming, fast cycling, most competitive sports) associated with increased stress levels on the body are responsible for suppression of immune cells. As the body takes a longer time to recover from these exercises of high intensity, the number and functions of immune cells including neutrophils, NK cells, T-cells, B-cells are altered, and this results in a delayed immune response. Heavy exertion increases the oxygen demand in the body which leads to physiological, psychological and metabolic stress which compromises the capacity of immune cells. Research suggests that high-intensity exercises performed for more than five hours a week, might be harmful to the body. Therefore, a mix of low, moderate and high-intensity exercises are recommended.
How exercise prevents low grade inflammation?
Quality exercise training in combination with a proper diet helps in producing cytokines from muscles such as IL-6, IL-8 and IL-15. High levels of these mediators keep the inflammation-promoting chemicals in check, thus reducing the chronic low-grade inflammation. Studies have found that moderate exercises help in stimulating release of IL 6 which supresses the release of a pro-inflammatory cytokine called TNF-α, thus lowering inflammation in the body.
How exercise reduces risk of respiratory infections?
A decreased risk of upper respiratory tract infections (URTI) has been observed with regular, moderate physical exercise as it enhances the surveillance by the immune cells in the respiratory tract mucosa. However, heavy exertion in high intensity exercises diminishes the surveillance activity of the immune cells, increasing the risk of infection. Although the immune system may return to normal after a few hours of the exercise bouts, each bout of exercise provides you with improved detective capacity of the immune system in the long-term to destroy pathogens and reduce the risk of infections.
Therefore, regular physical activity along with lifestyle changes can have a great impact on your immune system and provide you with a wide variety of health benefits. This new field of research “exercise immunology” has provided us with some insights into how our immune system responds to different kinds of exercise. So, keep these in mind and continue your daily physical activity without fail!
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- Martin S, Pence B, Woods J. Exercise and Respiratory Tract Viral Infections. Exerc Sport Sci Rev. (2009); 37(4):157-164.