Girls who were inactive during adolescence gained an average of 10 to 15 pounds more than active girls, according to results of a 10-year observational study of obesity. Total calorie intake increased only slightly and was not associated with the weight gains. These new results show that a previously reported steep decline in physical activity among adolescent girls is directly associated with increased fatness and an increase of body mass index (BMI), a measure of body weight adjusted for height.
The results of the Health and Growth Study, funded by the National Heart, Lung, and Blood Institute of the National Institutes of Health, will be published in an online edition of the Lancet on July, 13, 2005, and in the July 23, 2005, print edition.
Study investigators previously found that girls? leisure-time physical activity declined between the ages of 9 and 19 by an average of 7.5 brisk, 30-minute walks per week among all girls in the study.