High dietary protein restores overreaching induced impairments in leukocyte trafficking and reduces the incidence of upper respiratory tract infection in elite cyclists

Highlight • High-intensity exercise training (or overreaching) is associated with an increased incidence of upper respiratory tract infection in athletes. We have recently shown that leukocyte trafficking, an important aspect of immune surveillance required to detect and eliminate infection, is impaired during high-intensity exercise training. The current investigation shows that a high dietary protein during high-intensity exercise training restores leukocyte trafficking, and therefore aspects of immune surveillance, to levels observed during normal-intensity exercise training. This restoration of immune surveillance with a high protein diet occurred in parallel with a reduced incidence of upper respiratory tract infections in athletes.