We runners can be disciplined to a fault. We run through rain, snow, heat, and humidity because if you waited for perfect weather, you would rarely ever get a run in. However, that “get-it-done-no-matter-what” logic can be stretched to other circumstances and drive runners to push through illness and run when sick. Should you run when you’re sick? In today’s post, I want to look at the factors to consider in running when sick and knowing when to rest.
Running builds a strong immune system, but that doesn’t make you completely immune to catching the cold, flu, or stomach bug. Especially if you are training hard, just recently raced, or are exposed to illness frequently through work, school, or kids, you may find yourself under the weather – and illness does not take your training plan into consideration.
Runners are not by nature lazy people and the idea of skipping a run to spend extra time resting in bed is seriously unappealing. It’s hard enough to miss a run during the off season, but it can be even harder to make the appropriate decision of whether or not to skip a run when you get sick during an important training cycle and are approaching a goal race.
It can require more discipline to listen to your body and give it rest when needed than to go out for a run. In the era of Strava and Instagram, we are quick to praise those who run through illness or quickly after a surgery, rather than realizing that running when sick can be downright unhealthy.
Above/Below the Throat Rule
A general rule of thumb answers the question about running when sick by assessing the symptoms. If your symptoms are located in your head – running nose, watery eyes, headache, sneezing, stuffy nose – then you can run if it feels good. You may even find that a run helps clear out nasal congestion and reduces your headache. You of course still should rest if you feel that you need extra rest, but you can run without too much worry as long as you modify your training appropriately (see below).
If your symptoms are located in the throat or below – a sore throat, chest discomfort or congestion, swollen glands, cough, or upset stomach – then you should rest completely. If you have a stomach bug and are vomiting, you should rest.
Another good rule of thumb is that if you feel sick and are asking the question of should you run, then you are best just resting. You will not lose fitness in the time it takes to recover from a cold or flu, but you will quicken your recovery by resting.
Whether or not you abide by the “below the neck rule,” you should not run if you have a fever of 99 degrees Fahrenheit or above. Your core temperature raises during a run, which means if you run with a fever, you will cause your body temperature to increase even more. This can suppress your immune function and delay healing. Your heart pumps harder when your body temperature is increased, in an attempt to cool down, and so you put your heart under greater strain when running with a fever.
If you have a head cold and choose to run when sick, do not make this the week that you increase your mileage or do a hard interval workout – even if your training plan calls for it. Running for longer than 90 minutes or doing a hard speed workout stresses your immune system and if your body is already fighting illness, then you are only going to risk prolonging or exacerbating your illness.
Opt for easy effort runs of 30-45 minutes in duration and do not expect yourself to hit the same paces as you normally do when healthy. If it helps, run by time and leave the GPS watch at home, so you are not tempted to push too hard.
If you miss a few training days, do not try to make them up by cramming more mileage into the rest of the week or skipping a rest day. Simply resume your training plan as is, with the modification of having your first day back being an easy day.
Be Mindful of Conditions
Running in the dry and cold conditions of winter can worsen irritation of the nasal passages and mouth, while running in extreme heat can raise your core temperature and expend extra energy. If you suffer from seasonal allergies, be cautious about running outside to avoid allergens worsening your head cold symptoms.
Most of all, you are better off taking a couple days off to let your body properly recover, rather than to run and prolong your recovery period or affect your health and training down the road. Err on the side of caution and treat your body well. You will not lose fitness in just a few days off of running.
Do you run when you are sick? How do you decide when to rest?
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