Winter Running: Boost Your Immune System

Train Your Body How to Not Get Sick

Colds and coughs bring down legions of distance runners. Don't be one of them

Immune to It All

Train Your Body How to Not Get Sick // fit man drinking orange juice © Thinkstock

Image: Thinkstock

You’re at the peak of your training or you just completed a marathon, when suddenly you have a sore throat, runny nose, and fits of sneezing. You're not alone. Many long-distance runners report developing colds and other upper-respiratory infections (a.k.a. the "marathon sniffles") in the two weeks following a race, according to various surveys and studies. But isn't running supposed to make you healthy? While 30 to 45 minutes of moderate daily exercise does stimulate the immune system, the rigors of running longer distances temporarily weakens it. During the strain of a hard run, the body churns out the stress hormone cortisol, which suppresses immune function in large amounts. (Search: How can cortisol make me fat?) "The more intense the run, the higher the cortisol level," says Amesh A. Adalja, MD, an infectious disease-specialist. "We know it can be high enough to impair the immune system for up to three days following a race or a strenuous workout."

Marathons, in particular, can leave a runner vulnerable: "When you consider packs of sweaty runners high-fiving, along with spectators kissing finishers in congratulation, transmission of cold and flu viruses is inevitable," says Dr. Adalja. Fortunately, there are ways to boost your resilience. Think of it as training for your immune system.

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