Exercise And The Common Cold
Many of us catch colds, particularly in these cold, dark, wet winter months. At Goal Master, clients often ask us if it’s safe or beneficial to exercise when they have a cold. The answer is “it depends”.
I happen to be one of those exercise junkies who cannot miss a gym session – If I’m well enough to get out of bed, I’m well enough to train. At the opposite end of the human spectrum, some people use a runny nose as yet another excuse to avoid exercise altogether. Those of us at the ends of the spectrum need to read this blog.
So, what is the truth about the relationship between exercise and the common cold? Here is what you need to know.
Scientific research gives us relatively few clear answers.
The NHS reports that people who say they exercise five or more times per week have 43% fewer days of cold symptoms than people who say they exercise one or fewer times per week. The symptoms of fit people are 41% less severe than the symptoms of the unfit.1
The accuracy of these numbers can never be firmly established, because these sorts of observational studies can never accurately adjust for all the confounding factors, such as misreporting, stress levels, smoking, diet and exposure to germs.2 That said, the relationship between exercise and the length and severity of common colds is fairly compellingly established by the research. Stated otherwise, the research supports the long-held belief that regular exercise strengthens our immune system (in addition to driving countless other favourable health outcomes).
Making Colds Worse
The science also tells us that intense exercise causes stress and suppresses our immune system. Hard training when we have a cold can exacerbate symptoms and lead to bigger problems, including secondary infections, flu, pneumonia and worse. The advice to “sweat out” a cold is not good advice. That said, people do report improvement in symptoms following moderate exercise.
So, what does the science tell about when it’s safe to exercise and how much exercise we can do when we have a cold? Not much at all. No bright lines. However, many dozens of doctors and health and fitness professionals have expressed opinions on the subject. Right or wrong, their advice is remarkably consistent. Here are the “agreed” themes among them:
If symptoms are all in the neck or above, moderate exercise is a good thing (runny nose, headache, nasal congestion, sore throat).
If symptoms are below the neck or full body, do not exercise (chest congestion, wheeziness, fever, coughing, achiness, stomach ache).
Exercise moderately, and not intensely.
Stay well hydrated when exercising.
Wash your hands, cover your nose and wipe down your equipment to avoid infecting others.
Don’t linger in sweaty gym clothing after your work out.
Listen to your body. If it’s telling you stop, stop.
Beyond that, no one has much to say.
Though I cannot prove it, I personally believe in the old adage: “Treat a cold and it will last seven days, ignore it and it will last a week”. At least this has borne true for me since childhood. Medicine will alleviate symptoms, but only the passage of time will cure colds.
We do know that exercise will not cure or shorten a cold, though (in moderation) it may make you feel better and will keep you fit while you recover.
What about vitamin C and other supplements? People report that taking vitamin C, zinc or omega 3’s when you have a cold will help you recover faster. Some of the science involving short term mega-dosing of vitamin C and zinc acetate is quite promising.3 The science, though promising, is still inconclusive. In other words, supplementing might help, but might not. But even if it won’t help, it certainly won’t hurt (so long as dosages are limited to those recommended). And even if it’s only a placebo effect, it’s still an effect. So why not?
Getting Back To It
If you do take time off for exercise, remember that it’s only a hiatus. Your objective is to get back to exercise as soon as you are well enough. Doctors and other health professionals advise to take it easy as you start exercising again. Gradually ramp up until you feel strong enough and well enough to take it from where you left off.
I know I’m an outlier. I’m smart enough to know that training with pneumonia is not a good idea, but stupid enough to push the limits of common sense. So, my advice is to do as I say and not as I do.
1. “Can exercise ward off colds?”, NHS, www.nhs.uk/news/lifestyle-and-exercise (2010).
2. On average, regular exercisers are less stressed, smoke less and eat better than sedentary people perhaps?
3. “Is there finally something nutritionally we can do to alleviate the symptoms of the common cold?” Close, www.closenutrition.com (2017); “Vitamin C in the prevention and treatment of the common cold”, Bucher A et al., Am J Lifestyle Med (2016).