Trends in overweight and physical activity among U.S. military personnel, 1995-1998

The purpose of this study was to deter mine whether changes in physical activity patterns account for the increasing prevalence of obesity, utilizing a large, representative sample of male and female U.S. military personnel.

Data from the 1995 and 1998 waves of the Department of Defense Survey of Health Related Behaviors among Military Personnel were utilized. Overweight was defined as body mass index > or =25. Respondents were classified as physically active if they reported > or =3 days/week of vigorous activity. Three sequential multivariate logistic regression models were analyzed separately for males and females with overweight regressed on year of study (1995 or 1998), demographic characteristics, and physical activity.

Some 50% of military personnel in 1995 and 54% in 1998 were classified as overweight, representing a significant increase in overweight over the 3-year period for both males and females. Overweight military personnel were more likely to be male, older, African American or Hispanic, married, and enlisted personnel. Physical activity levels were high, with around 67% of the sample engaging in regular, vigorous physical activity. Although physical activity levels increased among male personnel between 1995 and 1998, there was not an independent association between physical activity and overweight, and changing physical activity patterns did not account for the increase in over weight from 1995 to 1998.

The U.S. military is experiencing a trend toward increasing overweight that mirrors the pattern among the general population. The results of this study suggest that the rise in overweight among the military is not explained by a decrease in physical activity.