A study from the Children's Memorial Research Center finds Chicago teens get less exercise than their counterparts around the state.
The center says the research shows the number of Chicago teens getting the amount of activity recommended by the Centers of Disease Control and Prevention is "strikingly low."
The CDC recommends several activities, including running or walking, 60 minutes a day.
That helps improve bone strength, reduce fat and increase mental health.
Chicago Public School teens were asked about the time they spent on the computer, watching TV and in physical education class.
The study found just 19 percent of the Chicago 12th graders got the recommended amount of physical activity.
In Illinois overall, 42 percent of 12th graders did.