CHICAGO—A study of 17 middle school students suggests that physical fitness gains made by obese children who participated in a lifestyle-focused physical education class during the school year were lost after the three-month summer break, according to a report in the June issue of Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives journals.

 

 

CHICAGO—A study of 17 middle school students suggests that physical fitness gains made by obese children who participated in a lifestyle-focused physical education class during the school year were lost after the three-month summer break, according to a report in the June issue of Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives journals.

Children increasingly live in an environment with reduced amounts of physical activity coupled with easy access to calories, according to background information in the article. This can result in obesity, poor cardiovascular fitness, insulin resistance, type 2 diabetes, high cholesterol and hypertension.

Aaron L. Carrel, M.D., and colleagues at the University of Wisconsin Children’s Hospital, Madison, previously conducted a randomized controlled trial in which 17 overweight children were assigned to participate in a lifestyle-focused, fitness-oriented physical education class for nine months. At the end of the trial, students in the class achieved significant improvements in cardiovascular fitness and also had reduced fasting insulin levels, which indicate a lower risk for diabetes. For the new study, the same children (average age 12)—all of whom remained at the same school and repeated the fitness class—were assessed again at the beginning and at the end of the next school year.

“Improvements seen during the nine-month school-year intervention in cardiovascular fitness, fasting insulin levels and body composition were lost during the three-month summer break,” the authors write. During the break, average fitness level as measured by maximum oxygen consumption—the amount of oxygen the body can use, with higher levels indicating better fitness—decreased by 3.2 milliliters per kilogram per minute. Percentage of body fat increased by an average of 1.3 percent, and fasting insulin levels also increased.

“Developing and evaluating interventions to influence students’ opportunities for healthful choices has been a focus of school-based health promotion research, including nutrition programs and physical education,” the authors write. “However, when interventions occur in a school-based setting, and are confined to the school year, an inherent question is one of sustainability.”

The children were not given any instructions regarding exercise over the summer, creating three months of unsupervised activity, the authors note. “These data show that in children, efforts to improve insulin sensitivity and reduce risk of type 2 diabetes mellitus and other morbidities of insulin resistance should include exercise intervention in a sustained manner to improve cardiovascular fitness throughout the year, not just during the school year,” they conclude.
(Arch Pediatr Adolesc Med. 2007;161:561-564.

Editor's Note: This study was supported by grants from Genentech Center for Clinical Research and the University of Wisconsin Sports Medicine Classic Fund. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

EDITORIAL: EFFECTIVENESS AND COST-EFFECTIVENESS DATA NEEDED ON CHILDHOOD OBESITY PROGRAMS

Although public health and medical organizations have encouraged action, more research is needed to determine what works to prevent or reduce childhood obesity, writes John Cawley, Ph.D., of Cornell University, Ithaca, N.Y., in an accompanying editorial.

“Specifically, the critical information that policymakers and educators lack is how to achieve the greatest reduction in obesity for the fixed budget they have available; in other words, how they can achieve the greatest ‘bang for the buck’,” Dr. Cawley writes. “Cost-effectiveness analysis (CEA) is the method that can answer this question because it compares various interventions in terms of their costs per unit of benefit.”

Legislators and others should be wary of acting without the results of such analyses, he continues. “While I appreciate that obesity seems to be the public health cause du jour and that there may be greater attention given to, and willingness to act on, this problem by policymakers in the near future than in the long run, there are also risks associated with rushing to implement unproven interventions.” These risks include the misallocation of resources, unintended consequences and a loss of credibility among policymakers.
(Arch Pediatr Adolesc Med. 2007;161:611-614. Available to the media pre-embargo at www.jamamedia.org)

Editor's Note: Dr. Cawley is an evaluator of the following school-based anti-obesity interventions: the Healthy Schools Program and Health Corps. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

For more information, contact JAMA/Archives media relations at 312/464-JAMA (5262) or e-mail mediarelations{at}jama-archives.org .

 

 

Topics #Fitness #Obese Children #Physical Education