DALLAS (AP) — Today’s kids can’t keep up with their parents. An analysis of studies on millions of children around the world finds they don't run as fast or as far as their parents did when they were young.On average, it takes children 90 seconds longer to run a mile than their counterparts did 30 years ago. Heart-related fitness has declined 5 percent per decade since 1975 for children ages 9 to 17.The American Heart Association, whose conference featured the research on Tuesday, says it's the first to show that children's fitness has declined worldwide over the last three decades."It makes sense.