COVID-19 is a terrifying wake-up call for out-of-shape Americans.

More than four in 10 U.S. adults are obese, and 60 percent have at least one chronic disease, putting them at high risk of serious COVID-19 complications—or worse. Individuals with chronic illnesses are 12 times more likely to die from the virus. 

For decades, health care professionals have cautioned people about the dangers of obesity. But those warnings have largely gone unheeded. Until recently, too many Americans viewed exercise as just the ticket to a beach body, not the first line of defense against deadly diseases.

COVID-19 is changing that mistaken belief. Now, it’s incumbent upon health professionals to help Americans get in shape.

While everyone knows that exercise promotes good health, many don’t understand how.

Exercise increases blood flow throughout the body, meaning that more immune cells can circulate at a higher rate. Over time, that immune response builds up. 

A study published in the British Journal of Sports Medicine found that for people who engaged in aerobic exercise five or more times per week, upper respiratory tract infection decreased by 40 percent over 12 weeks. Staying active also reduces body fat and inflammation, which helps to fend off infections and prevent chronic conditions. 

Americans are starting to finally realize that staying fit isn’t just about looking good—it’s about strengthening the immune system.

Fortunately, the fitness industry is trying to accommodate this mass awakening by moving classes outdoors and online for the first time. 

Further transformation of Americans’ relationship with exercise will require the help of exercise science professionals. Their job is to develop individualized wellness programs that consider a person’s age, health, culture and other factors that influence their ability to maintain a healthy routine. 

For example, someone at risk of developing high blood pressure may know they need exercise but have no idea where to start. An exercise science professional can help set realistic and achievable goals with something as simple as a short morning walk. That person can then develop longer-term habits that incorporate more vigorous exercise into their routine.

Or, exercise science experts can educate chronic disease patients about the ways physical activity can help manage their conditions, from reducing the pain associated with rheumatoid arthritis to increasing insulin sensitivity for diabetics. 

These professionals can also adjust their methods based on clients’ individual comfort levels. Many Americans still don’t feel safe entering brick-and-mortar gyms. In response, exercise science professionals can use other innovative tools and training models, such as remote platforms and outdoor workout settings. 

COVID-19 has disrupted our society. But it has also created an opportunity to improve our country’s health by transforming exercise into the primary weapon in our fight against the virus.

Alex Rothstein is an instructor and program coordinator for the exercise science degree program at New York Institute of Technology. This piece originally ran in Fortune.

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