The effect of a modern lifestyle on children's physical fitness levels

摘要

Q: CHILDREN'S LIFESTYLES ARE INCREASINGLY SEDENTARY. DOES THIS AFFECT THEIR OVERALL FITNESS? A. Aerobic fitness levels among children and adolescents in the United States are decreasing, but this phenomenon is by no means unique to the United States: declining fitness levels in young people have been reported elsewhere. Researchers in Canada, for example, used accelerometers (devices that measure a subject's change in speed over time) to evaluate the amount of time that Canadian children spend engaged in physical activity daily. They found that less than 10% of the children studied spent 60 minutes engaged in moderate-to-vigorous activity at least 6 days per week. Moderate-to-vigorous activity is defined by the Centers for Disease Control and Prevention (CDC) as activity that is six to seven times more intense than the state of rest for any given individual; this corresponds to brisk walking or jogging for most people. A group of researchers in Australia evaluated peak oxygen consumption (VO-2max, a standard measure of aerobic fitness) in 12- to 15-year-olds performing a shuttle-run test over a 5-year period.