The average American teenager is no more active than the average 60-year-old.  That's according to new research from the Johns Hopkins Bloomberg School of Public Health that tracked more than 12,000 people.  The study found that females are on average more inactive than males.  The only increase in physical activity was measured in young adults in their 20s.  

Many fall short of World Health Organization recommendations to engage in at least an hour of moderate physical activity a day between the ages of 5 and 17.

Photo: AOL