As a cardiologist I find myself talking to my patients often about the widespread benefits of cardiovascular fitness and exercise. During these unprecedented times, this is even more important as it relates to maintaining a healthy immune system.
In an interview in the Journal of Sport and Health Science published in March, 2020, Dr. Jeffrey A. Woods from the University of Illinois at Urbana-Champaign discussed how what we know about the benefits of exercise for influenza can help us in the new era of COVID-19. Dr. Woods’ research focuses on exercise immunology and how exercise can influence the immune system, the gut microbiome, and aging. In one study, he found that 30 minutes of exercise a day could protect mice from death due to influenza. In another study, he and his colleagues found that “regular, moderate cardiovascular exercise” in humans helps to maintain the benefit of the influenza vaccine throughout the entire season.
COVID-19, the novel coronavirus, is particularly important because we have little immunity to the virus and no clear available treatments or vaccines. Social distancing and self-quarantining are still the most important means of preventing spread at this time, but could exercise help to improve our resistance to infection?
Exercise promotes the “fight or flight” response in our bodies. This simulates early human’s evolutionary response to seeing a threat (a bear, a wild boar, etc). Exercise causes immune cells to increase in numbers and activity. This was noted as far back as 1902 when it was observed that Boston marathon runners had the same response as people with certain diseases. Although there is substantial evidence that aerobic exercise recruits immune cells, there is also recent evidence that resistance training and mind-body exercise, such as yoga and Tai Chi, have similar effects on our immune response.
Exercise has a multitude of benefits and during this pandemic lets help ourselves and help each other boost our immunity.
Stay healthy and stay safe everyone. We are all “in this together” and can all help to “flatten the curve.”