Physical activity & the immune system
Physical activity is widely considered to be one of the main components of healthy living, alongside a good diet and sleep pattern. It’s role in preventing chronic diseases is well-established, with physical inactivity being responsible for over five million premature deaths each year. Now, in the midst of the ongoing pandemic, it’s perhaps more important than ever to curate a healthy lifestyle, and engaging in physical activity is one of the easiest ways to help reduce your risk of ill-health!
One way that physical activity can help prevent poor health is through strengthening your immune system – a network of cells and proteins that defend your body against infection. Randomised controlled trials have highlighted that regular physical activity can elevate levels of the antibody immunoglobin A (IgA), which coats the mucosal membrane of your lungs and other areas of the body through which viruses and bacteria could enter. Similarly, regular activity also increases the number of CD4+ T cells in the body, which are responsible for altering the immune system and regulating its response. Both of these mechanisms help to reduce your risk of infection.
Whilst regular physical activity helps to strengthen our immune system, it can also act as an effective medicine against infectious diseases in other ways. Engaging in physical activity can help to protect you from risk factors of infection, such as developing obesity, diabetes or respiratory and cardiovascular conditions, with epidemiological studies concurrently finding that Covid-19 symptoms are much more severe in these vulnerable populations. It is also known that physical activity can reduce stress and chronic inflammation, reducing the likelihood of fatal infections developing. Again, novel research suggests that many Covid-19 fatalities have been a result of an uncontrolled inflammatory response. Resultantly, minimising any risk factors is crucial to preventing the long-term effects and mortality rate of Covid-19, and can be readily achieved through physical activity.
A new systematic review by Chastin and colleagues demonstrates that engaging in regular physical activity can not only strengthen the immune system and reduce the risk of dying from infectious disease by more than a third, but it also provides novel evidence to suggest that it can significantly increase the effectiveness of vaccinations too. As mass rollout of the Covid-19 vaccine continues worldwide, and we begin edging closer to normality, the impact of physical activity in driving its success should not be understated.
Despite being conducted early on in the Covid-19 pandemic, much of the data reviewed concerned the effect of physical activity on the risk of falling ill and dying from infectious diseases, such as pneumonia. With pneumonia being a frequent cause of death for Covid-19 patients, the findings from the review remain highly relevant to the current pandemic response. In fact, a further randomised control study found that an active person is 50% more likely to have a higher antibody count than someone who is not active. Whilst this has clear benefits for our own health, it also has useful implications from a cost-effective standpoint – making every dose count!
Physical activity is undeniably important in the fight against infectious diseases, both now and in the future. Helping to reduce the number of vulnerable populations can be done by simply making physical activity more accessible, particularly to those in the more vulnerable groups. Shifting the narrative of physical activity away from traditional exercise, to instead appreciating each and every movement you make throughout the day, dramatically opens up the opportunity for engagement. Whether that be dancing around the kitchen whilst the kettle is boiling, getting some gardening done, or walking to the local shops instead of driving, it all adds up. Every move matters in combating infectious diseases, and helping you to live a happier, healthier life!
