Earlier this week, beginning last Friday, my body was struck by a cold. It started with a sore throat and moved slowly into my respiratory track, where Kleenex became my new best friend. My body ached, I was pretty tired, and sounded like I was speaking with my nose plugged (which I was...).
However, I still trained. I didn't go to the gym as often or work out as hard as I would if I wasn't sick, but I still got my butt to the gym and did what I could.
On two of my workout nights, I was pretty winded. Everything I did felt like I had just run hill sprints. I was breathing heavy and all I wanted to do was lay down and close my eyes (which I did a few times... I didn't care what people thought).
Now, the controversy over all of this is whether one should work out when they are sick, or if they should just stay home.
On one side, some scientists and doctors feel that working out can suppress the immune system and make your cold worse. On the other, working out might help strenghten your immune system, by increasing white blood cell activity, and make the cold go away faster. Then, right in the middle is the finding that working out when you're sick doesn't change the path of your cold one bit.
I came across this article in the New York Times from 2005 that said, unless your cold was completely debilitating, it doesn't matter one bit if you exercise or not.
Then, in 2003, researchers from Ball State found the same thing: that exercising with a common cold does not influence its duration.
In my experience, I've always exercised whether I've been sick or not, unless I was so sick that I couldn't see straight. Since I'm a consistent exerciser, missing too many workouts because I have a cold would actually make me feel worse than getting my exercise accomplished, albeit at a lesser intensity. I've even worked out one week after having major surgery (I had part of my intestine taken out), and worked out two days after having my tonsils taken out (which was the best thing I've ever done to reduce allergies and colds).
The bottom line for working out when you're sick: do it, especially if you're a trained individual. You'll just have to cut back on the time and intensity, but you'll be happy that you did it. However, avoid exercise if your symptoms are quite severe - no one wants to see you get sick in the gym or on the field.