The Gatorade Sports Science Institute has published a report
on the relationship between exercise and illness, especially
concerning the common cold. The level of exercise is important,
however, because heavy exercise might actually suppress the
immune system. We’ve summarized that report here so you
may use exercise wisely as a weapon in your arsenal against
researchers are convinced that moderate exercise can protect
against illness, others feel that too much exercise can have
the opposite effect. Here are the pros and cons for athletes,
coaches, and trainers to consider.
Exercise & Colds
Research shows that regular exercise helps the immune system
in a number of ways:
• Moderate exercise can lower
stress hormones, an enemy to the immune system.
• Those who exercise report
suffering from fewer colds than those who don’t.
• Exercising almost daily
can cut the number of sick days in half over a three- to four-month
the immune system returns to pre-exercise levels not long after
exercising, each workout seems to offer the immune system a
boost that could reduce the risk of infection over the long-term.
The bottom line, regular moderate exercise can help prevent
Much May Do Opposite
Yes, there could be too much of a good thing when it comes to
exercise and the immune system. Although moderate regular exercise
can boost the immune system, heavy exertion may actually lower
your resistance to illness.
have shown a steep drop in immune function lasting from six
hours to three days after athletes have run for two or three
hours. That’s because heavy exercise actually increases
stress hormones. And as we mentioned earlier, high
levels of stress hormones tend to dampen the immune system.
Though athletes need to train hard for competition, that training
need not increase their risk for infection. Here are a few ways
to minimize the impact of stress on your immune system.
• Keep your everyday life
stress to a minimum.
• Eat a well-balanced diet
so you get adequate vitamins and minerals. Contrary to popular
opinion, vitamins C and E do not boost the immune system.
• Get ample sleep on a regular
schedule, avoiding chronic fatigue and over-training.
• Avoid rapid weight loss.
• Try not to touch your eyes
and nose until you wash your hands thoroughly. This is how infections
• If you compete in the winter,
get a flu shot.
• Use carbohydrate beverages
before, during and after heavy training or endurance events.
About one quart of carb beverage per hour of heavy exercise
can raise blood sugar levels and lower stress hormones. Water
alone doesn’t do it.
Regular moderate exercise could help keep you from getting the
common cold and other infections. However, heavy exercise and
over-training can do the opposite – increasing stress
hormones and lowering your resistance. Reduce everyday stress,
eat a balanced diet, get enough sleep, and drink carbohydrate
beverages when you’re training hard.
tip of the month was edited from an article by David Neiman,
Dr., P.H., director of the Human Performance Lab at Appalachian
State University, Boone, NC. The Gatorade Sports Science Institute
can be accessed on the web at gssiweb.com.
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