One easy, effective tip to combat the health risks of inactivity

Thanks to the marvels of modern technology, we have seen major clinical advances across the entire healthcare landscape—from life-saving medical diagnostics to innovative treatments for some of the most challenging diseases. But while technology has huge benefits, it also has huge pitfalls. And the biggest one? Physical inactivity. But, a new study suggests that a simple and easy change to your daily routine may counteract the negative effects of inactivity.

Think about how much exercise you really end up getting on any given day, especially with most exercise facilities closed for the foreseeable future and lockdown measures keeping most of us home for the majority of the day. Plus, what little exercise you may have gotten going from one patient exam room to the next may now be replaced by telehealth appointments from your living room.

Even before quarantine life was the new norm, consider that, for the majority of Americans, desk-based jobs have virtually replaced manual labor, elevators have replaced stairs, motor vehicles have replaced active travel, and most shopping and errands can now be accomplished online with the use of apps. Indeed, every year, more people are working traditionally white-collar jobs, where they spend long hours sitting down, expending minimal physical effort. In fact, the number of sedentary jobs has increased by 83% since 1950, with physically active jobs now comprising < 20% of the US workforce.

And it’s not just the lack of exercise that’s troubling. Prolonged sitting itself has been linked to negative health consequences. Studies have shown that, even after adjusting for physical activity, sitting for long periods is linked to worse health outcomes, including heart disease and cancer—the two leading causes of death in the United States.

To make matters worse, exercising your way out of the health hole created by too much sitting can be a big challenge. While high levels of exercise can reduce some of the associated health risks, research suggests that once you sit for more than 10 hours, cardiovascular risk still skyrockets. So, what can those who live a sedentary lifestyle do to combat its negative health effects? The solution may be to exercise smarter, not harder.

Spreading out physical activity

Hitting the gym for an hour after 8-10 hours of prolonged sitting is certainly better than not partaking in physical activity at all. Unfortunately, it doesn’t do enough to counteract the damage that long periods of inactivity can inflict, like raising levels of postprandial plasma lipids (PPL)—a group of substances comprising oily, waxy compounds like triglycerides, which are a risk factor for heart disease. To reduce PPL levels, spreading physical activity out into shorter, more frequent bouts may be effective, according to authors of a recent study published in Medicine & Science in Sports & Exercise.

To arrive at this finding, researchers measured whether 4-second sprints on a specialized exercise bike conducted 5 times per hour for 8 hours could improve PPL levels in 4 men and 4 women. Results showed that those who sprinted on the exercise bikes had a 31% decrease in plasma triglyceride incremental area under the curve and a 43% increase in whole body fat oxidation—even when they sat for 8 hours in the same day—compared with those who sat for 8 hours without exercising. That positive result came after a combined 160 seconds, or just 2 minutes and 40 seconds, of exercise per day done in between periods of sitting.

“Given that these improvements were elicited from only 160 seconds of non-fatiguing exercise per day, it raises the question as to what is the least amount of exercise that can acutely improve fat metabolism and other aspects of health,” the authors wrote.

Making moving a priority

Evidence from the above-mentioned study suggests that if Americans want to reduce their health risks, they need to make a concerted effort to reduce—or at least break up—the amount of time they spend sitting. While hopping on an exercise bike and giving it your all for 4 seconds, 40 times a day, is a creative way to make it happen, adults need not go to such imaginative lengths to make a difference. The US Department of Health and Human Services’ 2018 Physical Activity Guidelines for Americans promotes a wide range of activities and workout durations, stating rather simply that “adults should move more and sit less throughout the day,” and that “some physical activity is better than none.”

For substantial health benefits, adults should commit to doing moderate-intensity workouts for 150-300 minutes per week, or vigorous-intensity activity for 75-150 minutes per week, according to the guidelines. While cashing in those 150 minutes of vigorous-intensity activity in a single day can help, “aerobic activity should be spread throughout the week,” the guidelines stated, in alignment with data from the 4-second cycling study.

Thinking about movement differently

For the 80% of us living a largely sedentary lifestyle, the key takeaway from a mounting pool of research is simply: sit less. Taking the next step and figuring out new ways to move more often is a much different question that depends on your health goals, age, access to open space and equipment, and many other factors. “For every 20 minutes of sitting, try to stand for 8 minutes and move around for 2 minutes,” said Erin Michos, MD, MHS, associate director of preventive cardiology, Ciccarone Center for the Prevention of Heart Disease, in an interview with Johns Hopkins Medicine. “Take baby steps. It doesn’t have to be vigorous. Just stand up and move your muscles.”