Nov 7, 2023
How endurance running impacts the immune system

Whether you’re a lifelong runner or new to the sport, it’s important to understand the impact running has on the immune system.

The immune system is complex. As white blood cells help fight off infections, your body temperature and blood oxygen levels change. Hormones such as cortisol and adrenaline modulate how blood cells work.

What you eat, how much sleep you get, how stressed you are, what medications you take and your medical history all impact how the immune system functions.

A recent story from Right as Rain by UW Medicine detailed the relationship between endurance running and an athlete’s immune system. Below is an excerpt from the Right as Rain by UW Medicine.

The effects of endurance running on the immune system have been well-researched. In one study, a group of runners had blood drawn at regular intervals while running for three hours. Afterward, researchers looked at their white blood cells and hormone levels. They observed an initial increase in most types of white blood cells and both cortisol and adrenaline levels. Following the endurance exercise, there was a subsequent reduction in some types of white blood cells. The immune system returned to normal within 24 hours of recovery.

While this is interesting, what does it actually mean for runners?

Researchers have found a relationship between the intensity and duration of runs and immune function. Moderately intense workouts tend to strengthen the immune system. For most people, this means an hour run at a steady pace.

Running 10 miles or more or running to exhaustion, however, may temporarily weaken the immune system. This impairment of immune function generally lasts only for a few hours, although for some people, it may take several days to recover, especially for those with an already weakened immune system. Marathon runners have been observed to be up to six times more likely to get the common cold after a race.

Should I be worried about sickness if I run a lot? The answer is not to avoid long or hard runs, but rather to run smarter. Prevention is key. Simple steps can be taken to reduce your risk of illness:

  • Limit time spent in public or crowded spaces, especially after longer distance runs.
  • Maintain a strong immune system by sleeping seven to eight hours per night.
  • Eat healthy foods, including sufficient carbohydrates to maintain your glycogen stores, plus plenty of fruits and vegetables.
  • Get your annual vaccinations.
  • Wash your hands regularly, avoid touching your face, and carry a small bottle of hand sanitizer.
  • If it makes you more comfortable, wear a face mask and keep your distance from other runners.

The data is currently mixed as to whether antioxidant supplements are of benefit to runners trying to prevent infection. Supplementation of vitamins is only helpful if someone is deficient in a vitamin (more is not better).

While training, try to avoid overcrowded running trails and let the immune system fully recover after a particularly intense or long workout. If this is not a possibility, a simple way to bolster the immune system is to make sure your glycogen stores are replete between workouts by fueling with a well-balanced diet.

To read the full story from Right as Rain by UW Medicine, click here. 

Shop see all »

75 Applewood Drive, Suite A
P.O. Box 128
Sparta, MI 49345
website development by deyo designs
Interested in receiving the print or digital edition of Training & Conditioning?

Subscribe Today »

Be sure to check out our sister sites: