A recent study presented at the European Society of Cardiology Congress 2023 has shown that sedentary time in childhood and young adulthood is linked to heart damage, even for individuals within the normal ranges for weight and blood pressure.
The study included 766 children who were followed from 11 to 24 years old. The children wore smartwatch activity trackers for one week when they were 11 years old and again when they were 15 and 24 years old. At 17 and 24 years old, the left ventricular mass of their hearts was measured. Left ventricular mass is related to the risk of strokes, heart attacks, and death. The purpose of the study was to measure the relationship between sedentary time and heart damage in children and young adults. The heart measurements were controlled for a variety of factors including age, sex, blood pressure, body fat, smoking, physical activity, and socioeconomic status.
The results showed that the participants were sedentary for an average of 362 minutes per day, or about 6 hours per day, when they were 11 years old. At 15 years old, the average sedentary time increased to 474 minutes, or almost 8 hours per day. By 24 years old, they were sedentary for an average of 531 minutes, or almost 9 hours per day. For each 1-minute increase in sedentary time between 11 and 24 years old, left ventricular mass increased by about 0.004 g/m2. A previous study in adults showed that a similar increase in left ventricular mass over a 7-year period doubled the risk of heart disease, stroke, and mortality.
An author of the study noted that cumulative sedentary time is linked to heart damage regardless of other clinical measures. To prevent heart damage, parents should encourage their children to move regularly through various forms of exercise and to limit their time using social media and playing video games.
Sources: ESC, Science Daily
