Childhood obesity has more than tripled in the past thirty years with more than one-third of kids and teens now considered overweight or obese, according to the Centers for Disease Control.
At Barnard Elementary School, ESPN sportscaster Bonnie Bernstein and Olympic runner Rod Dixon kicked off the "Kids Rock" youth fitness program designed to combat childhood obesity.
"If you can get kids exercising and involved in activity, it will translate into the classroom," said Dixon. "It's been proven that their concentration and focus improves if they are active."
Over the years, long-time educators say they've witnessed firsthand childrens' bodies changing and obesity becoming an epidemic.
"It has become a big problem," said school counselor Sandra Montgomery.
Studies show obese youth are more likely to develop high cholesterol, high blood pressure, diabetes, joint pain and not to mention social stigma and poor self-esteem.
"Obesity means when you get really fat," said a student. "I think you should eat more healthy. I think when you eat, you still get fat, but I think you should eat more healthy."
"I exercise to get stronger muscles and [...] so I can have more energy," said another student.
In the last couple of years, administrators say the school lunch program has included an afternoon snack of fruit or vegetables and already they say kids' eating habits are changing.
"They have broccoli, they have cauliflower," Montgomery said. "Some of them are starting to acquire a taste for those vegetables."
But with growing emphasis on standardized test scores, many states and school districts have rolled back their requirements for physical education. In D.C. public schools, elementary students are only required to get 30 minutes of PE each week. For grades 6-8, the minimum requirement is 45 minutes.
When not in school, parents say they try and encourage their children to stay active.
"Not only does it help their body, it helps their mind," said parent Kandace Tolson. "It helps them as they get older and that's something they'll take into adulthood."
During the next month, students in the "Kids Rock" program will run a total of 26.2 miles, the length of a marathon. On Wednesday, they completed mile one.