Focus on Fitness: Will exercise reduce risks of colds, flu or coronavirus?

By Gloria Schwartz

Are you concerned about catching a cold, flu or the novel coronavirus? According to the World Health Organization (WHO), coronaviruses “are a large family of viruses that cause illnesses ranging from the common cold to more severe diseases” such as serious respiratory syndromes. A novel coronavirus is a new strain not previously identified in humans. The current novel coronavirus has been named COVID-19.

As of early March, what is known about COVID-19 is that it’s more deadly (estimates are as high as 3.4 per cent death rate compared to less than one per cent for seasonal flu). There are over 90,000 known infected people worldwide and 3,000 deaths. As of March 10, Canada had 93 confirmed cases of COVID-19 with one death so far. Older adults and people with underlying chronic conditions are most at risk as are health care workers. Most of the confirmed cases haven’t become seriously ill. Some people are asymptomatic and may unknowingly transmit the virus. By contrast, seasonal flu impacts tens of thousands of Canadians each year, including children, and millions of people worldwide.

What are some common-sense measures you can take to reduce your risk of catching colds or flus? Get a flu shot to protect yourself and others. Some people can’t, due to medical conditions. Unfortunately, there’s no vaccine yet for COVID-19, but there’s a race to develop one. Reduce environmental exposure, for example, avoid shaking hands and refrain from touching surfaces with bare hands in public spaces such as door handles and shopping cart handles. Use a paper towel or your sleeve, your arm, shoulder or hip if you must open a door or press an elevator button. Avoid touching your face. Move away from people who are coughing or sneezing. You may not be able to completely avoid crowds and coming into contact with shared surfaces. Regular thorough handwashing with soap and water for 20 seconds is one of your best defences. Use hand sanitizer when you’re on the go such as after touching shopping cart handles, gym equipment and handrails. If you have symptoms of a cold or flu, sneeze and cough into your elbow and stay home to prevent spreading germs.Other than avoidance and hygiene practices, what can you do? According to Harvard Medical School, a healthy lifestyle is your best strategy for a healthy body that includes a strong immune system. If you keep yourself fit and well-nourished, you avoid smoking and second-hand smoke, you don’t drink alcohol excessively, you maintain a healthy weight, get adequate sleep and manage stress, and you take steps to avoid infection, your immune system will work well to protect you from infectious diseases such as viruses and from some chronic diseases. Exercise directly promotes good circulation, which “allows the cells and substances of the immune system to move through the body freely and do their job efficiently.” While the report concludes that a scientifically proven direct link between exercise and our immune system hasn’t been established, it also states that moderate regular exercise appears to enhance your immune system’s responses to bacterial, viral and other antigens. The WHO states that “general healthy-living strategies are a good way to start giving your immune system the upper hand.”

The Cleveland Clinic states that regular exercise and a healthy diet can boost your immune system by increasing the diversity of the gut microbiota or gut bacteria in your intestines.

Starting in our 20s, our immune system declines on average by two to three per cent per year. However, regular exercise partially prevents it from declining. A study of 125 older adults ages 55-79 who participated in endurance cycling for most of their adult lives found they had immune systems comparable to people decades younger. They had better immune systems, as measured at the cellular level, compared to a control group of inactive adults. The good news is that you don’t have to be an endurance adult and cycle hundreds of kilometres to strengthen your immune system. Regular moderate exercise – an average of 20 minutes per day – improves your immune system. The authors of the study believe that regular exercise in old age also improves the efficacy of vaccines, meaning seniors who are active and vaccinated are even less likely to catch the flu and pneumonia than seniors who are vaccinated but inactive. The conclusion is that staying physically active as part of a healthy lifestyle may help your immune system protect you from viruses.

Click here to read "From the Editor" by Michael Regenstreif for commentary on how COVID-19 is affecting the Jewish community in Ottawa.