My thinking of training while sick is this...training isn't recommended if you are sick from the throat down. So pass on the training if you are experiencing stomach problems, trouble breathing or a fever/chills. However, if it is the throat up which can be nose running, headache or stuffy head, studies have shown that a little low intensity exercise can actually strengthen the immune system. Don't expect to gain fitness but you may feel better overall than if you need nothing. You must always listen to your body and in most cases if you just rest your body entirely for a day or two, you can be back to normal sooner than if you try to train while your body is fighting a cold or virus.
When I do get sick (which is rarely...I guess I should stop saying that before I get sick again) I don't like to reach for the medicine. Actually, Karel and I don't have anything in our place besides ibuprofen (which was mostly for my aches post-kona). I am not a big believer in reaching for the meds everytime something hurts. If you are injured, you probably didn't listen to your body when it hurt and you just tried to get through training. Sometimes you can survive and be fine with an ache, but like in my case, my ache turned into 5 monthes of no running. I didn't listen before kona but you better believe i listened post kona. I sure learned a lot with my injury...
Anways....Usually, when you feel the symtoms of getting sick your body is already doing its thing by fighting whatever you have. The hotness, runny nose, chills or aches are usually because of the body trying to kill whatever it is that got into the body. These are all symptoms. Therefore, if you reach for medicine you are only trying to make yourself feel better from those symptoms. You aren't really trying to make yourself any healthier. However, if the "sickness" prevents you from daily functioning and life(includes work, planned events which can't be cancelled or sleep. Unless you are a Pro or about to race an important race, training technically is not part of life) then you may want to find the best medicine to help you make it through the day. Again, don't think that taking medicine every 4 hours is going to make you feel 100% the next day..it may, but perhaps you need to look at your daily routine and see why you got the virus in the first place. Kids, eating out, work...yes, great places to spread germs. However, in need of more sleep, stress and an increase in training...I think I have my culprit for why my immune system was a little down. I am sure I am in contact with germs and virus's everyday but if I step up my training and feel a little stressed with school, my body is having to work overtime and that virus ultimately wins.
So...I thought instead of buying some meds I would go the natural route. No, I didn't just lay around in misery and light some incents and eat herbs (hehe) I went to the farmers market and bought myself some healthy, antioxidant rich fruits and veggies. YUM!!! And after cutting up all the veggies (which were only $11!!!! Yes people...buy fruits/veggies when they are in season, especially at a farmers market) I made myself a yummy smoothie w/ vanilla whey protein, a little strawberry yogurt, organic skim milk, cinnamon and my fruit. This one came out supper creamy!