Overweight boy with fast food on sofa at home

(© New Africa - stock.adobe.com)

JYVÄSKYLÄ, Finland — Sitting around all day has unfortunately become a constant part of modern life. We sit through school, at work, and even in our leisure hours as we stare into our smartphones and other devices. However, a new study is issuing a dire warning for children who don’t make an effort to be physically active. While you might think that working hard or fierce exercise may stress out your heart, it turns out that doing nothing all the time actually puts more of a strain on this vital organ.

According to a recent Finnish study, published in the Journal of the American Heart Association, more sedentary behavior during childhood places a strain on the heart by adolescence. Simply put, being physically inactive, not going outside to play, and too much screen time forces a young heart to work harder than it normally would at that age.

Researchers from the University of Jyväskylä and the Institute of Biomedicine at the University of Eastern Finland warn that this rise in inactivity so early in life is a recipe for heart disease — the number one killer in the world.

“Youth spend nine to ten hours a day being sedentary,” says Dr. Eero Haapala from the Faculty of Sport and Health Sciences at the University of Jyväskylä in a media release, “and only one in ten adolescents accumulated 60 minutes of daily moderate to vigorous physical activity. These are worrying figures.”

Children outside bored
Researchers in Finland found that more sedentary behavior during childhood places a strain on the heart by adolescence. (© EvgeniiAnd – stock.adobe.com)

The research, conducted over eight years, followed 153 adolescents from ages 6-8 to 15-17. It measured their sedentary time (activities like sitting, lying down, etc.) and physical activity levels using specialized monitors worn on their chests. At the end, cardiac function tests assessed how hard their hearts had to work to pump blood.

The findings reveal that kids who accumulated more sedentary time and less moderate-to-vigorous physical activity (like running, cycling, etc.) from childhood to adolescence had higher cardiac workloads as teens. Their hearts had to work harder to supply the body with oxygenated blood. On the other hand, those who stayed active, especially with vigorous exercise, had lower cardiac workloads.

So, why does this matter? Study authors explain that an overworked heart could lead to serious problems down the road, like left ventricular hypertrophy (thickening of the heart muscle) or even heart failure. It’s a red flag for potential cardiovascular issues.

The Finnish team thinks the increased cardiac workload partially stems from childhood obesity and insulin resistance, common side-effects of inactivity. When the data accounted for body fat percentage, however, some of the heart function differences disappeared.

As for the solution, Haapala’s team says it all comes down to encouraging kids to move more and sit less from an early age. Building healthy habits like regular exercise, limiting recreational screen time, and maintaining a healthy weight by limiting junk food could pay dividends for their heart health now and later in life.

“High levels of daily moderate to vigorous physical activity should be a normal part of childhood and adolescence as it improves heart health, but also general well-being,” Haapala emphasizes.

About Chris Melore

Chris Melore has been a writer, researcher, editor, and producer in the New York-area since 2006. He won a local Emmy award for his work in sports television in 2011.

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