Its that time of the year again! While we can enjoy getting cozy with our blankets in anticipation of the Holidays, it’s also the time of the year where illness is rampant. If you have been a good boy or girl this year and stuck with a regular exercise program, you have no doubt improved your defenses against microorganisms that so readily enter our bodies. Research definitely supports the fact that a regular exercise program can improve your immunity.

Unfortunately, sometimes you will still get sick, no matter how hard you try not to. Then the question is whether or not you should exercise?

When you are sick, chances are it is difficult for you to even get out of bed. Here the answer is clear — rest is best.

But what about the times when you feel good enough to squeeze in a workout? You aren’t quite 100%, but still feel like you can do something. Is it better to wait it out and rest, or will exercise help you get through your cold?

The answer to this question is probably best directed towards the intensity of your workout. While I am a huge fan of high-intensity interval training (HIIT), HIIT workouts should be avoided when you are under the weather. According to research, excessive stress from an intense workout routine can weaken your immune system while it is in an active battling mode. 

And this makes sense. You don’t feel good because your body is diverting all of its available energy to getting rid of whatever has invaded your body. When you exercise at a high-intensity, you instead pull that energy away from the battlefield, and your immune cells do not have the resources they need to get you back healthy again. So when you are sick, I recommend avoiding HIIT workouts until you have felt 100% better for at least 2 days or so. 

Now that I have delivered the bad news, the good news is that you can still exercise. In fact, moderate intensity exercise (slow jog, fast walk, leisurely biking) can actually boost your immune system. From a realistic standpoint, this also makes sense. Exercise does raise your body temperature and improve blood flow, which can make your body a nasty host to invaders. Elevating your body temperature, similar to a fever, makes your body’s environment unfavorable to to viruses and bacteria. Improving blood flow may also help your body’s immune cells get to where they need to be to fight the infection. Further, a bit of exercise may also help you feel better and improve your mood. So, if you are up to it. Do what you can, but be careful not to overdo your workout.

Take Home Point

When it comes to exercising when sick, light to moderate exercise is best. This is one instance where nobody will fault you for resting, but if you are up to it and miss those workout endorphins, avoid high-intensity exercise and enjoy a leisure workout. Go for a nice walk or bike ride, just enough to jump your heart rate up a bit. Be patient while you are sick, you will be back in the swing of things before you know it!

Here is the recommended workout to perform when you are sick!

If you are ever concerned that you are not getting better, or feel severely sick, do not hesitate to contact your physician.