Overweight and aerobic fitness in children in the United States/Mexico border region.

OBJECTIVE To study overweight and aerobic fitness among children in the third and fourth grades of elementary schools in a city in the United States of America (El Paso, Texas) and a city in Mexico (Chihuahua, Chihuahua) that are on or near the border between those two countries, and to compare the results from those two cities with earlier findings for other children in the United States. METHODS We followed the El Paso children (427 boys and 385 girls, 93% of them of Mexican descent) from third to fourth grade and assessed the change in their body mass index (BMI). In the city of Chihuahua we cross-sectionally measured the BMI of a sample of third grade children (221 boys and 237 girls) and a sample of fourth grade children (268 boys and 215 girls). BMI and triceps skinfolds were measured for all the children studied in the two cities. BMI was used to assess risk for overweight (at least the 85th percentile BMI for age and gender) and overweight (at least the 95th percentile BMI for age and gender) in all the children. The distance that El Paso children ran in nine minutes was used to assess their aerobic fitness (aerobic fitness was not measured in the Chihuahua children). The data from El Paso were collected in 1999, 2000, and 2001, and the Chihuahua data were collected in 2000 and 2001. RESULTS In the El Paso boys, overweight significantly increased in the one year from third grade to fourth grade, from 22% to 28%, while risk for overweight significantly increased, from 37% to 44%. In the El Paso girls, risk for overweight significantly increased over the same one-year period, from 29% to 37%. The El Paso boys and girls were significantly less fit when compared to samples of children from throughout the United States. Third and fourth grade children from Chihuahua had similar rates of risk for overweight and of overweight when compared to the children from the same grades in El Paso. CONCLUSIONS Children in both El Paso and Chihuahua were more overweight than were non-Hispanic white children throughout the United States. In addition, the children in El Paso were less aerobically fit than were non-Hispanic white children and than were other Mexican-American children in the United States. These results clearly show that efforts should be made in the border regions of both Mexico and the United States to develop physical activity and nutrition programs to help stem rising rates of overweight.