Viral Infection in Athletes

Abstract

Most epidemiological and clinical studies suggest that systematic physical activity increases the
body's immune capacity against infections. On the contrary, much evidence suggests that prolonged
vigorous exercise training favors the development of infections, particularly viral ones. This twoway
exercise effect is described as a “paradox” of exercise. Some theories have been developed
about these adverse effects of exhaustive exercise on cellular and humoral immunity, such as
open window theory, the J-curve, and the S-curve. However, some questions remain regarding the
prevalence of these mechanisms, and the level of the exercise that leads to immunosuppression.
Other factors favoring the onset of viral infections in athletes are stress, climatic conditions, incorrect
nutrition, crowding, etc. The most common infections are viral infections of the upper respiratory
tract, influenza, infection from the Epstein Barr virus. There is no information available to correlate
the volume of physical stress with COVID-19 infection. The best preventive measures are to avoid
exercising during a febrile infection, vaccination, adequate nutrition, and reduce stress..