It's not 11 p.m., but a group of University at Buffalo researchers knows exactly where your children are.
Four professors are leading a scientific study to determine the connection between physical activity of teenagers and preteens and living near parks and neighborhood green space.
The researchers are seeking volunteers -- parents and teenagers -- to participate in the 10-week, federally funded study.
For three weeks, the parents and youngsters will wear a device that measures the intensity of activity, while the youngsters will wear global positioning system-equipped watches to record their movements.
"This grant is heavily based on technology, newer technology like the GPS," said James N. Roemmich, associate professor of pediatrics at UB and principal investigator on the study.
GPS devices are growing in popularity for parents who want to keep tabs on their children, for men and women who want to track a wayward romantic partner or for employers who want to ensure their drivers aren't lingering too long at a coffee shop.
Warren Buckleitner, editor of the Children's Technology Review, said use of GPS watches, a tool that researchers of an earlier generation would have loved, should help the investigators get the best data possible.
"It's really wonderful that researchers are starting to use these technologies to better understand children's behavior," Buckleitner said. "If Jane Goodall were [conducting research] today, she would probably be putting GPS devices on her apes."
When people live near parks, their level of physical activity rises by 25 percent, according to research cited in the Buffalo Olmsted Parks Conservancy master plan. Their risk of obesity also drops.
If people have safe, convenient access to well-kept parks and other free recreational opportunities, they will take advantage of them, said Thomas Herrera-Mishler, president and chief executive officer of the conservancy.
The key is making the parks, playgrounds and athletic fields accessible to pedestrians and bicyclists, said Mark V. Mistretta, principal landscape architect with Wendel Duchscherer Architects & Engineers.
"Kids tend to be more active if they've got a place to run around," Mistretta said.
Daemen College officials found this to be true after the school helped build two small playgrounds in Buffalo, one in the Fruit Belt and one in the Seneca-Babcock neighborhood.
Children in the college's after-school programs love playing on the slides, swings and monkey bars, and they have to be reminded to finish their homework first, said Cheryl Bird, executive director of Daemen's Center for Sustainable Communities and Civic Engagement.
In this study, researchers want to pin down whether people who live near parks and other green spaces are more active because they are using the areas.
First, they digitally mapped all of Erie County and assigned a score to each parcel based on its proximity to green space.
They are seeking a child 12 to 15 years old and a parent from 80 participating households -- divided between those who live near the green space and those who don't.
"We're interested in how the built environment [such as sidewalks, parks and parkways] influences children's choices to be physically active," Roemmich said.
The parents and children will be fitted with a pager-sized activity monitor, known as an accelerometer, that they must wear as long as they are awake.
The device measures not just how far they move but the intensity of the movement. The devices are worn for three weeks out of the 10-week study.
For the same three-week period, the children will wear a GPS-equipped watch.
"Sounds like a perfect marriage of technology and the research question," said Timothy M. Osberg, a Niagara University psychology professor who is not involved in the project.
To test what children do with extra time, the researchers also will ask half of their young participants to cut their television and computer use by 50 percent during the study period.
"Will they engage in other sedentary behavior, or choose to do other activities?" Roemmich asked.
This is the third year of the three-year study, which is supported by $1.4 million from the National Institutes of Health.
Co-investigators are Samina Raja, associate professor of urban and regional planning; Li Yin, assistant professor of urban and regional planning; and Leonard H. Epstein, professor of pediatrics.
Roemmich said the researchers aren't having trouble finding willing participants.
The children receive up to $245, while the parents get up to $105, if they follow all of the requirements of the study.
The data generated through the study is kept confidential.
GPS technology is growing in popularity, and parents are giving their children cell phones equipped with GPS chips or installing tracking devices in the cars of teenage drivers.
Some critics say this is an invasion of privacy.
But Judy Thurnherr of Cheektowaga said children shouldn't have an expectation of privacy and she would have no trouble participating in a study like this.
The teacher's aide was having a picnic on a spread-out blanket last Sunday in Delaware Park with her husband, John, and their 4-year-old granddaughter, Grace.
John Thurnherr said he wouldn't have wanted to wear a GPS watch as a teen.
"When you become a parent, then it sounds like a much better idea," he said.
For more information on the study, call 829-6695.