Immune what? This is a typical question that people ask me after I tell them what I do for a living. Your immune system is how your body fights off infections (bacterial, viral or fungal) on a regular basis.
As New Yorkers, we are bombarded daily with germs from the subway, door handles, the gym. An interesting question is how is the immune system affected by exercise? Does the intensity of exercise matter on the effect on your immune system?
On average, most of us experience about 2-3 colds per year. How does exercise affect this?
There is very good evidence that regularly exercising boosts your immune system and keeps you less susceptible to infections. Researchers at Appalachian State showed that those who walked regularly at a quick pace had 50% less colds than those who didn't exercise regularly.
Interesting, very intense exercise (like in those training for a marathon) for prolonged periods of time actually causes pertubations in the immune system making it weak. The body to produce naturally steroids and adrenalin & these hormones act to weaken the immune system for up to 72 hours after the event, making you more susceptible to infection. Not willing to give up your training program, there is some evidence that eating probiotics and food before and during the workout helps maintain the strength of your immune system
What about if you have a cold? Should you continue your exercise program or wait till you're 100% better?
Light to moderate exercise when you have a cold actually stimulates your immune system while intense bouts of exercise weakens it and may prolounge your infection.
Bottom line- regular exercise helps keep you healthy!