Exercise and COVID-19

How antioxidants released during exercise may reduce symptom severity.

Posted May 06, 2020

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The benefits of regular exercise are extremely well documented. Stories have been published for years about how exercise pays physical and psychological dividends with few, if any, drawbacks. Meanwhile, evidence continues to mount that a multitude of chronic illnesses are associated with a sedentary lifestyle, especially if it is coupled with a diet that is high in processed sugars, saturated fats, and an abundance of starchy and empty carbohydrates.

To avoid these health risks, maintain a healthy weight and promote wellness. Even limited exercise can be extremely beneficial. It has been linked with improved mood and data suggests that this is because it can positively impact one’s brain chemistry and hormonal levels. To this latter point, recent studies have even found that it can make many of the symptoms associated with menopause more manageable.

In addition to these benefits, regular exercise may strengthen individuals’ immune systems. While a healthy immune system is always important, it has become invaluable during the coronavirus pandemic. True, exercise cannot prevent one from being infected with the virus, but recent research from the University of Virginia suggests that exercise may prevent patients from developing acute respiratory distress syndrome (ARDS), which appears to affect between 3 percent and 17 percent of COVID-19 patients. It is one of the deadliest complications associated with the disease. The study found that 45 percent of patients who develop COVID-related ARDS will die.

Exercise and the Antioxidant EcSOD

Exercise does not fight the virus itself or grant individuals some kind of special immunity. Rather, the Virginia study found that exercise increases the production of an antioxidant produced in the muscles known as extracellular superoxide dismutase (EcSOD). In addition to increasing EcSOD levels in existing muscle tissue, more exercise, particularly weight training, also produces more muscle tissue. More muscle tissue means an increase in the potential amount of EcSOD that the body can produce.

Once secreted into the bloodstream, EcSOD is then redistributed throughout the body to protect cells by serving as a potent anti-inflammatory agent. For patients with ARDS, this means EcSOD is sent to the lungs to reduce the inflammation there. As the danger posed by ARDS depends upon how widespread the inflammation in the lungs becomes, and consequently how much the inflammation deprives the body of oxygen, EcSOD levels could be the difference between a mild case of ARDS and a deadly one.

Dr. Zhen Yan, the author of the review, believes that EcSOD may be used as a potential treatment for a wide variety of conditions in addition to ARDS, though research into the full spectrum of its effects is still in its infancy. EcSOD’s potency as an anti-inflammatory agent relative to others that exist in our body and diet is still being studied.

Obesity as a Risk Factor

As Dr. Yan asserts, EcSOD levels could at least partially account for the disparities in symptoms among individuals infected with the novel coronavirus. Unfortunately, ARDS is not the sole complication that arises from the disease, and it is likely that EcSOD levels are but one factor impacting how ill patients become. As the virus is still new and comprehensive studies have yet to be conducted, there are far more questions about the virus and the illness it causes than there are definitive answers.

However, initial research and anecdotal evidence from hospital workers does suggest that there are numerous risk factors that can make a severe case of COVID-19 more probable. It has been widely reported that those who are immunocompromised or over the age of 65 are at a higher risk for severe illness, as are those with any one of the following conditions:

  • Chronic kidney disease
  • Chronic lung disease
  • Diabetes
  • Liver disease
  • Moderate to severe asthma
  • Serious heart conditions

Yet another factor that appears to exist independent of diabetes is obesity, especially if one has a body mass index (BMI) of 40 or higher. Studies are finding that obesity may be second only to age in determining whether or not a person becomes critically ill with the disease.

Researchers are not certain why obesity seems to independently make patients more susceptible to severe COVID-19 symptoms, but it is possible that it could also be tied to inflammation. Researchers have found that adipose tissue (fat) secretes cytokines that trigger inflammation. The more adipose tissue in the body, the more the body remains in a state of low-grade and chronic inflammation that has been shown to make individuals more susceptible to certain viral infections—most notably severe strains of influenza-like 2009’s H1N1.

If this is true, one can think of an increase in adipose tissue as having the opposite effects on the immune system as an increase in muscle tissue. The former hinders patients’ immune systems during incidents of infection, while the latter enhances them. Consequently, any effort to reduce one’s BMI, provided one is obese, could potentially reduce the risk of developing complications associated with COVID-19.

The fact that exercise can reduce obesity and leads to the increased production of EcSOD are two more reasons why everyone should try to find at least 150 minutes to exercise each week, provided they are physically able to do so.

Dr. Ahmad reports no conflict of interest. He is not a speaker, advisor, or consultant and has no financial or commercial relationship with any biopharmaceutical entity whose product/device may have been mentioned in this article.