In a surprising study reported in the New England Journal of Medicine, researchers found that adolescent girls in the United States all but stop any kind of regular physical activity during their adolescent years.
Black and White
More than 1,200 black girls and over 1,100 white girls were followed for more than nine years – from age 9 or 10 to age 18 or 19. At the start of the study, both groups were relatively active, but by the end of the study their activity levels had diminished greatly. There was nearly a 100 percent drop in activity for the black girls and about 65 percent for the white girls. Overall, the activity level of these adolescent girls diminished by more than 80 percent.
Contributing Factors
- For both groups, a lower level of parental education was associated with greater decline in activity. There is a similar relationship between years of education and physical activity in women of all ages.
- For both groups, a higher body-mass index was associated with a greater decline in activity. The proportion of young people who are overweight has doubled in the past 20 years.
- For black girls, pregnancy was associated with decline in activity. Nearly one in four became pregnant during the study.
- For white girls, smoking was associated with decline in activity. More than 27 percent reported smoking.
More Risks
- More than 60 percent of young people who are overweight have one or more cardiovascular disease risk factors. One in four young people who are overweight have at least two risk factors, according to the Centers for Disease Control and Prevention.
- Girls who exercise and maintain a healthy weight are less likely to get breast cancer and type 2 diabetes.
Summary
Regular exercise could be a big part of the solution. But more study is needed on how to encourage America's youth to exercise, not smoke, avoid unwanted pregnancy, and keep weight at a healthy level. |
