Exercising While Sick

Although I don’t imagine it crosses most peoples mind, I have been asked on occasion whether I think it is a good idea to exercise when you’re sick. Like so many other questions, I would have to answer this with extreme vacillation and say “yes and no”. Exercise is always important for your body - especially if we define exercise as simple activity as opposed to inactivity - but there are times when your bodies metabolic processes need to be focusing their attention somewhere other than external exertion (like combating an illness).

If you’re young, the answer to this question is often intuitive and, in fact, made for you... If Mom says stay in bed, you stay in bed. Even at a young age, however, perhaps as you progressed through college you noticed that nothing about your body was quite the same when invaded with some or another virus or parasite. Your attention may not have been as sharp, your energy depleted, even your coordination could have seemed muddled. We have a tendency to pay less attention to such details as we grow older and certain activities like playing football, studying all night or throwing a wad of paper at the cute girl across from you become less important and, therefore, less indicative of our overall well being. Certainly being sick on the job will result in a tough time, but it doesn’t always compare to the stress of being sick during finals.

Ultimately, if you have a mild illness, it is not a bad idea to get up and move around a little. In this case, we’ll define “mild” as little to no fever, and annoying but not habit altering symptoms like sneezing, headache, body ache, cough etc.. If you take this sort of mild intrusion on your body as a signal to shut down and you lie in bed until the symptoms subside, you may in fact be aiding the illness, not your body. The reason for this is found in the body’s complex transportation system for nutrients, fluids, and our battle systems like antibodies and white blood cells (although white blood cells rarely get involved with mild illness). This transportation system is based upon pressures, changing pressures which require alterations back and forth between and within vessels to keep the transport going. If we lie stagnant, our body is only able to utilize the natural pressure gradients which already exist in the vessel systems. If we move, however, the contractions of our musculature helps change the pressure as well, making transport easier. Thereby, as your body goes through killing the bug in you, it has an easier time both getting new combatants to the intruder in the first place and in removing the illness once it has been found. Lying in wait may allow a mild illness to spread more easily since it is not necessarily bound to the same sort of transport as your body’s defenses. All of a sudden your mild illness is no longer mild in a few days.

The flip side of this equation is a more severe illness - usually associated with more severe symptoms like high fever, possible rashes, mouth or nose sores, and a cacophony of other fun things no one wants to think about unless they find reading medical journals entertaining as I do. In this case you are probably under the supervision of a doctor (or at least Dr. Mom) and you do as they say. A more substantial illness will invoke further defenses in your body to work like the white blood cells I mentioned earlier. In this case, movement doesn’t assist your body in the creation of these cells no matter what you do. In fact, the added metabolic energy required to produce your new combatants puts such a strain on your system that using further energy for exercise can be damaging to your cause. In this case, you should move only when necessary - for food or when nature calls - and all other time should be spent in rest. Most people don’t have the inclination to exercise with this sort of illness - in fact they are not inclined to do much of anything, but if you are a die-hard, take careful account of what your body is telling you. If you get up to go to the bathroom and you’re exhausted by the time you return to your bed, don’t try to eek out a light run later that day after you’ve had a quick nap.

Either way, if you do decide to exercise while you are sick, scale back your activity immensely. Wether a strong or weak illness, your body is still focused on removing that illness at the moment and is not going to perform up to a normal high standard you may ask of it. Usually just getting up and walking around 15 minutes once or twice a day is plenty. If you choose to go to the gym, a very easy cardio workout of no more than half an hour may be acceptable if you are naturally used to exercise when healthy. Sitting on a recumbent bike at a low resistance or walking on a treadmill at 2-2.5 miles per hour will increase your heart rate enough to help the transportation processes I mentioned earlier without totally exhausting you. Strength training should be generally avoided because you are not in a physical condition to make progress with a strength workout and strength workouts don’t inherently maintain a high heart rate which is the necessary component for pressure changes.

Finally, pay attention to your body. If just getting to the car to go to the gym is a struggle, don’t pursue a workout! If, on the other hand, you have been lying in bed for 3 days and your symptoms just wont change or go away, try getting up and moving around a little bit - not too long - but see how it feels. You may be hastening your body on the road to recovery.