Children and teens, it's time to quit the screens and keep your feet moving. A new study has found that a sedentary lifestyle during childhood increases the risk of heart attacks and strokes later in life.

Researchers found that the lack of physical activity in childhood raised heart attack risks later in life, even in those with normal weight and blood pressure.

"All those hours of screen time in young people add up to a heavier heart, which we know from studies in adults raises the likelihood of heart attack and stroke. Children and teenagers need to move more to protect their long-term health," said study author Dr. Andrew Agbaje, of the University of Eastern Finland.

The team evaluated 766 children and asked them to wear a smartwatch with an activity tracker for seven days when they were 11 years old. The same study was repeated when the participants were 15 and 24. The children were sedentary for an average of 362 minutes a day when they were 11 years old. This increased by an average of 169 minutes as they reached young adulthood (24).

"Children were sedentary for more than six hours a day, and this increased by nearly three hours a day by the time they reached young adulthood," Agbaje said.

When the participants were 17 and 24, the researchers assessed the weight of their heart's left ventricle using echocardiography, a type of ultrasound scan. They then analyzed the association between the level of inactivity during 11 to 24 years of age and heart measurements between 17 and 24 years after adjusting other factors such as smoking, body fat and blood pressure.

"Our study indicates that the accumulation of inactive time is related to heart damage regardless of body weight and blood pressure," Agbaje noted.

The findings suggest that a one-minute increase in sedentary time between the ages of 11 and 24 results in a 0.004 g/m increase in left ventricular mass between 17 to 24.

"Parents should encourage children and teenagers to move more by taking them out for a walk and limiting time spent on social media and video games. As Martin Luther King Jr. once said, 'If you can't fly, run. If you can't run, walk. If you can't walk, crawl. But by all means, keep moving,'" he added.