Should I Work Out When I’m Sick?

Should I Work Out When I’m Sick?

by Amanda L. Dale 14 Feb 2020

As a personal trainer, I am used to clients cancelling sessions when they’re not feeling well.  Yet recently when a client of mine called me to tell me she was diagnosed with the flu, she then said, “don’t worry - I’ll still come in for my session.” 


I was aghast.  Who in their right mind would want to drag their sick body to the gym when they can barely get out of bed?  There is an increasingly pervasive idea, especially among those who exercise regularly and are generally in good health, that an illness can be “knocked out” or stopped in its tracks with a vigorous, sweaty workout.


Similar in concept to the “feed a cold, starve a fever” adage whereby you try to shorten the duration of a cold by eating certain types of foods, the idea of using exercise to cure an illness is fundamentally flawed.  When you’re sick, your body craves rest and recuperation – and the more severe your symptoms, the more days you probably need to take off from intense exercising.


The colloquial rule among health and fitness experts is that if your symptoms are primarily “above the neck” – meaning coughing, sneezing, a runny nose, or even a mild earache, you’re probably OK to perform light exercise such as walking.  An exception to the “above the neck” rule is running a fever, during which you should skip exercise entirely.


When symptoms are primarily “below the neck” – think nausea, body aches, chest congestion, or diarrhoea, you’re probably better off taking a rest day (or two) and focusing on recovery.  In either case, the best advice is to listen to your body and be honest about how you’re truly feeling before you dive into a workout.  If your head is pounding, your throat is sore, and your body feels weak, there is probably not much utility in forcing yourself through a workout as you may feel worse when you finish.


Your doctor will always be the best judge of whether you are cleared for exercise, so try not to self-diagnose, especially when it comes to contagious disease such as colds or the flu, or if you’re planning to interact with other people (such as a group exercise class) for exercise.  Infecting others in the quest for one more workout is not a risk worth taking, no matter your regular routine.


If you’re worried about losing progress during your down time, know this: most people don’t suffer an actual decline in performance or muscle mass until 10-21 days off exercise. Once you’re better, keeping a consistent exercise routine can actually keep your immune system stronger in the future.


When you are finally feeling better and ready to recommit to your fitness routine, make sure to start back gradually with a more moderate version of your regular workout, and stay hydrated with water and electrolytes throughout the effort.  With careful attention to healing and wellness and a few good rest days behind you, you’ll return to the gym feeling better than ever!