Researchers link womens' obesity to inactivity during teen years

• Decreasing physical activity during adolescence seems to play a major role in weight gain among girls as they transition from children to women.
• Inactive girls gained an average of 10 pounds to 15 pounds more than girls who were active between the ages of 9 and 19, according to a study appearing in the July 16 issue of The Lancet.
• The number of calories consumed increased marginally and did not appear to be associated with the weight gain.
• "It does present a strong argument that physical inactivity in this age group is an important contributing factor to the development of obesity," said Dr. Robert Kramer, medical director of the Better Eating and Activity for Children's Health (BEACH) Clinic at the University of Miami School of Medicine.
• Results from the 1999-2002 National Health and Nutrition Examination Survey (NHANES) suggest that about 16 percent of children and adolescents aged 6 to 19 are overweight.
• A previous report had found that girls' recreational exercise declined between the ages of 9 and 19 by an average of 7.5 brisk, 30-minute walks each week.
• The researchers noted only small differences in BMI between "active" girls and "inactive" girls at the age of 9 and 10.
• In the following nine years, however, inactive girls had triple the gains in BMI and were about 10 to 15 pounds heavier.
• "It's pretty well acknowledged throughout the research and literature that self-reported food intake is generally underestimated," Kramer said.
• "One would hope that when a study like this comes out that people can use it as a springboard to bolster the argument for physical activity," said Samantha Heller, senior clinical nutritionist at New York University Medical Center in New York City.
• "We need to have a variety of fun and interesting ways to motivate children and adolescents to move their bodies," she said.