Should You Run When Sick? When not to run and how to modify your training

For a little perspective, the idea of running while sick if you are not a habitual runner sounds a little crazy.

No one’s mother said to any child, “oh you are not feeling well?  Go for a run!”

Most moms (and dads) will tell you to rest, drink your fluids, and try to eat something.

And that advice still holds true for runners.

When you first start feeling the symptoms of a cold or flu take a rest day and skip your run.

Running is a deliberate stressor on the body, which is a good thing when you are healthy, but can needlessly divert healing resources away from your illness.

If you want to get better faster, then allowing your body to attack your invader without distraction is the best route.

The most important thing to remember about running when sick is that you should always err on the side of caution if given the choice.

You are not going to ruin your fitness by pushing your workout back a day, or even by taking a few days completely off from running.

Yes, runners are obsessive creatures, but two or three days off will not negatively impact your fitness. We looked into this in great detail for our post on How Long Does it Take to Lose your Running Fitness post.

Be smart and be patient, and your body will thank you in the long run, pun intended

But what if your sickness is mild, but lingers on for days or even a couple weeks?

A general rule of thumb is that if your symptoms are above the neck, a run could be okay and might even help move things around a bit.  That would include a little nasal congestion or a runny nose.

But if you have a fever, body aches or fatigue, sore throat, coughing, nausea, or chest congestion, it’s far better to stay home and rest.  

Anything that is affecting your lungs is a clear sign not to run.

If you try to run anyway, you’ll likely feel a burning sensation in your lungs or the top of your throat as your body struggles to stop you from doing such a foolish thing.

Your heart is forced to work harder as it tries to both power your run and deal with the stress of the illness.  If you happen to have an underlying heart issue, either known or unknown, running while sick can expose you to extra risk.

Another time to toss out the rule of thumb is when you go ahead and run with a head cold and you come back feeling worse. 

That’s your body telling you to chill out and relax with a cup of hot tea.

Taking a couple days off or even a couple weeks off will not impact your fitness very much at all.

Another good rule of thumb here is that you can gain back any fitness lost in about the same time as you took off.

So if you needed to rest for 2 weeks, you can get back to your pre-sickness level in about 2 two weeks.

This is all very individual, of course, with some runners bouncing back quicker than others, but taking the time to heal will not completely derail all your progress.  But fighting this process certainly can.

What can you do to help get better faster?

When you’re too sick to do much of anything, it’s pretty clear you should stay in bed and rest.

But when you are more borderline, it can be hard to know what makes sense.  After all, runners hate to get out of their routines or risk their hard-earned fitness, right?

But you will get through this as long as you play it safe and don’t try to push through it.

Besides rest, the first thing you’ll want to focus on is hydration. 

When your body is fighting an active infection, it needs more fluids than usual to do its job.  Dehydration will make everything worse.

This is one of the times where drinking to thirst may not be enough, so aim for a little more than usual.  If your urine is pale yellow, that’s a good sign that you are doing it right.

Next up is nutrition. 

If you can tolerate a variety of foods, this is definitely the time to focus on the most nutrient dense options, like a rainbow of fruits and vegetables.

As far as supplements go, a greens supplement is going to be far better for you than a multivitamin.

We looked at the research on greens vs multivatiins here and greens were clearly better.

There have been some interesting studies showing that for marathon runners or other heavy exercisers, taking a little extra vitamin C can help prevent and shorten the common cold.

A few studies have shown zinc to be helpful as well.

What can you do instead of running?

If your issues are mainly in your lungs, but the rest of your body is feeling okay, you can try some gentle non-aerobic activity.

That could be light yoga, some mobility or stretching, or even some lighter strength moves that don’t get you breathing hard.

If you are feeling up to moving a bit more, try heading out for a walk instead of a run.

This should also be your first choice before you attempt a run.  You’ll know fairly quickly if it was the right choice if it feels pretty good during and after.

If you are wiped out after your walk, it’s time to go back to another rest day.  Then the following day, you can try a walk again.

Once you have a day or so of walking behind you and you are feeling better, you can try a run.

I always advise a shorter than normal run, just as a test to make sure that you are really on the mend.  If that goes well, you should be able to return to your normal routine in a couple of days.

Of course, if you have any cardiac-related symptoms while running, that is also a sign that you should stop immediately and talk to your doctor.

This would be shortness of breath, heart palpitations, irregular heart beats, chest pain, wheezing.  These are serious signs that shouldn’t be ignored, whether you are recovering from an illness or not.

The typical common cold lasts about 7-12 days, so try to be patient and allow your body’s defenses to do their job.  You’ll be back to running before you know it without losing much fitness at all.

For me, I’m at the stage where walking and a little light strength training feels good right now.  I’m laying low and drinking lots of hot tea with lemon, just like what my mom used to make me when I was little.