Approximately 80 per cent of confirmed COVID-19 patients have mild symptoms, make a good recovery and don’t need respiratory support, while others become extremely unwell and need life support. Professor Zhen Yan at the University of Virginia set out to find out why outcomes are so mixed.

Yan found regular exercise may reduce the risk of complications in people with COVID-19, as well as offering the potential for alternative treatment approaches going forward.

He studied an antioxidant called extracellular superoxide dismutase (EcSOD) that’s released by the muscles and into the bloodstream during exercise.

His work “strongly supports” the possibility that higher levels of EcSOD in the body can prevent or at least reduce the severity of acute respiratory distress syndrome (ARDS) – one of the worst outcomes of the COVID-19 virus.

EcSOD does this by hunting down free radicals, binding to organs and protecting tissues from attack by the virus.

“Our findings strongly support that enhanced EcSOD expression from skeletal muscle…which can be redistributed to lung tissue, could be a viable preventative and therapeutic measure in reducing the risk and severity of ARDS in COVID-19 patients,” he said.

Research suggests that even a single session of exercise increases the production of the antioxidant, prompting Yan to urge people to find ways to exercise, even while maintaining social distancing.

Cardiovascular exercise is thought to drive the highest immediate levels of EcSOD production, however, strength training increases muscle mass, meaning it also plays a part in the equation.

Between three and 17 per cent of people with COVID-19 patients will develop ARDS – this percentage goes up once people are hospitalised to between 20 and 42 per cent, as the more extreme cases succumb to the virus.

“We often say that exercise is medicine. This insight into the role of EcSOD in the body is a perfect example of how we can learn from the biological process of exercise to advance medicine,” Yan said.

“While we strive to learn more about the mysteries of the superb benefits of regular exercise, we don’t have to wait until we know everything before starting to take advantage of this benefit.”

Yan said EcSOD may also prevent multi-organ dysfunction syndrome – in which multiple organs begin to fail.

The antioxidant is also being proposed as a potential therapy for diabetic retinopathy, a complication of diabetes that can lead to blindness.

Low levels of EcSOD are seen in heart disease, kidney failure and osteoarthritis.

Find out more: faculty.virginia.edu/yanlab