When Laurie Beyer, a seventh- and eighth-grade teacher in the Rio Linda Union School District in Sacramento, Calif., began her classroom career eight years ago, the last subject she ever thought she'd be teaching was phys-ed.

But due to budget constraints, Rio Linda eliminated three teaching positions and three assistant teaching positions in physical education last year. Prohibited by law from cutting phys-ed completely, Rio Linda assigned gym duties to its classroom teachers.

"It's nothing any of us want, but instead of complaining, I just see it as learning a new curriculum," said Beyer, who now teaches 20 minutes of phys-ed a day.

She's not alone. From California to Iowa, from Colorado to Massachusetts, cash-strapped schools are gutting their phys-ed programs, letting go of teachers, reducing the minutes of instruction or, in some cases, eliminating physical education altogether.

Schools point the finger at the Bush administration's No Child Left Behind Act, which mandates that schools meet strict testing requirement in core subjects like English and math. The resources required to meet those standards, administrators say, leave little left over for non-core programs. But with the cuts in physical education coming at a time when childhood obesity rates are alarmingly high, health advocates fear that ultimately, children's health will be left behind.

"Physical education is a critical part of a complete education and every student deserves to be physically educated," says Charlene Burgeson, the Executive Director of the National Association for Sports and Physical Education. "The schools that are reducing physical education programs are everywhere," she said.

Recent research from the Centers for Disease Control and Prevention indicates that 15 percent of children and adolescents age 6 to 19 are overweight, double the rate of two decades ago. In fact, NASPE has increased the recommended amount of physical activity for children age 5 to 12 from 30 minutes to at least 60 minutes per day.

"We now know that making time for physical education and physical activity does not reduce academic learning and it may actually increase it," say Dr. Charles B. Corbin and Dr. Robert P. Pangrazi, of Arizona State University, the lead authors of the recently revised study, Physical Activity for Children: A Statement of Guidelines for Children Ages 5-12.

"Our research shows that children who are physically active during the day in school are much more likely to be physically active after school as well," say the authors.

Despite the obesity epidemic, school districts already feeling the financial pinch say the federally mandated NCLB is forcing tough choices. While the federal government has increased overall education funding, districts receive only about 10 percent of their budgets from Washington. The majority of their funding comes from state and local government, and state budgets are being slashed.

"It was something we did not want to do, but were forced to do because of the dismal state of the economy," Rio Linda Union district spokesperson Heidi VanZant said. "It is a wrenching time to be in public education," she said.

But some say schools are just trying to avoid complying with NCLB.

"It's been my experience that schools quick to seize on the requirements of NCLB are using the changes as an excuse for why they can't do these things," said Hayes Mizell, a Distinguished Senior Fellow at the National Staff Development Council, an organization dedicated to the professional development of educators. "They're really trying to avoid accountability," he said. Mizell believes schools need to use imagination when faced with reforms.

That is exactly what schools like Rio Linda Union, the largest elementary school district in Sacremento County, Calif. have done. According to John Baggett, the school's director of educational services, the district has addressed phys-ed concerns by looking for creative ways to integrate physical education into a greater health and wellness curriculum that was implemented this school year within each class.

Using a Macmillan/McGraw Hill textbook, the classroom teacher includes lessons of nutrition, health, character building and phys-ed. While teachers are not certified phys-ed teachers, the school has provided training to prepare for the curriculum. An added benefit, Baggett says, is that these teachers often know their students' needs much more than a phys-ed teacher who is teaching hundreds of students.

And so far, he's heard mainly positive feedback. "Teachers have really learned to take the ball and run with it," Baggett said, adding, "no pun intended."

And schools across the country could soon be facing even more requirements under NCLB if a new bill passes. Sen. John Cornyn, R-Texas, a member of the Task Force on Health Care Costs and the Uninsured, stepped up to plate in June by introducing the Physical Education in Schools Bill, S. 1276, which would revise NCLB to include national guidelines for minimum standards of health and physical education, since the requirements are currently left up to states.

Cornyn contends, "While it is certainly critical that our children are proficient in the basic subject of mathematics, English, and science, it is also important that they have access to quality physical and health education programs that will provide the foundation for healthy lifestyles, and that's why I support a physical education requirement in our schools."

But with schools already strapped with testing standards and budget cuts, it remains to be seen how a physical education performance standard might be received.

And as Mizell believes, it goes back to the old question, "How much can schools do?"

Click back to FOXnews.com tomorrow to read "Gym Class Goes Online to Fill Phys-Ed Cuts," Tuesday in Technology.