With less than two weeks until race day, marathoners should be doing everything they can to stay healthy, especially as cold season arrives. Your immune system has two jobs; immunity from germs and inflammatory for injury. Runners before and after a long event (like the marathon) are more susceptible to catching a cold because the immune system is working hard on the inflammatory defense. Cytokines (fighter cells) have immune types and inflammatory types, which work differently under exercise stress.

A study published in the Journal of Sports Medicine looked at the level of cytokines in the blood pre, during and post exercise. The subjects were marathon runners, half-marathon runners and military cadets. This study found that post race, there was a significant increase in the plasma volume of inflammatory cytokines but there was not an increase in the volume of immune cytokines. In some of the subjects, there was actually a reduction in the immune cytokines in post-race testing. Your body is producing so many of the inflammatory cells to treat your muscles during the race, you are not producing the cells need to fight off germs. The suggested time frame for the immunity suppression in this article was up to 72 hours post race.

What should you do about it? Make sure you are getting enough sleep, washing your hands and taking some kind of immune booster in the coming weeks, even after the marathon. It is also important to make sure your are eating right and staying hydrated. You have done all the work, now it’s time to enjoy the day healthy!

Nielsen, H. Oktedalen, O. Opstad, P. Lyberg, T. Plasma Cytokine Profiles in Long-Term Strenuous Exercise. Journal of Sports Medicine. April 2016. 7186137.

Kathleen Leninger, PT, DPT, NY Custom PT & Performance 295 Madison Avenue #1026 New York, NY 10017 212-682-7860