It's not enough to be involved in organized sports. Health experts say unstructured outdoor playtime is essential to children's health.

Some 16,000 citizens, more than 200 health and youth-related organizations and the National Wildlife Federation recently petitioned Surgeon General Dr. Regina Benjamin to make outdoor recreation a priority of her service.

Recently Dr. Benjamin, U.S. Health and Human Services Secretary Kathleen Sebelius and Michelle Obama announced a program to promote the health of Americans through physical exercise and improved nutrition. The petition calls on the Surgeon General to include outdoor recreation in the program by urging parents to get their kids to engage in unstructured play in backyards, parks and green spaces.

"The medical, education, and environmental communities ask the surgeon general to recommend that all American children and their families take time everyday to ... interact with the natural world," said Rebecca Garland, executive director of the National Wildlife Federation's Be Out There campaign, in a prepared statement. "Today's children have had less contact with nature than any generation in human history."

A Kaiser Family Foundation study recently found the average American 8 to 18 year old spends an average of 7 hours 38 minutes each day interacting with electronic entertainment media -- more than the equivalent of a full-time work week. The National Coalition for Promoting Physical Activity cites a 2005 study showing more than 30 percent of teens failed to meet national recommendations for moderate to vigorous physical activity.

"Children who are outdoors are more physically active than those who sit in front of a television or computer," said Dr. Kimberly Avila Edwards of Southwestern-Austin, Dell Children's Hospital, supporter of the petition. "Physical activity, including being outside in fresh air, plays a critical role in the treatment and prevention of pediatric and adult health issues. Combating obesity, heart disease, diabetes, joint problems and even depression will take a coordinated effort across a broad spectrum of organizations. We support Dr. Benjamin and look forward to collaborating for a solution."

Looking for more from the Post-Gazette? Join PG+, our members-only web site. You'll get exclusive sports content, opinion, financial information, discounts from retailers and restaurants, and more. Our introduction to PG+ gives you all the details.