Edward H. Ip, Santiago Saldana, Grisel Trejo, Sarah A. Marshall, Cynthia K. Suerken, Wei Lang, Thomas A. Arcury and Sara A. Quandt
Obesity disproportionately affects children of Latino farmworkers. Further research is needed to identify patterns of physical activity (PA) in this group and understand how PA affects Body Mass Index (BMI) percentile.
Two hundred and forty-four participants ages 2.5 to 3.5 in the Niños Sanos longitudinal study wore accelerometers that measured daily PA. Several PA-related parameters formed a profile for conducting hidden Markov modeling (HMM), which identified different states of PA.
Latino farmworker children were generally sedentary. Two different states were selected using HMM—less active and more active. In the more active state; members spent more minutes in moderate-vigorous physical activity (MVPA). Most children were in the less active state at any given time; however, switching between states occurred commonly. One variable—mother’s concern regarding lack of PA—was a marginally significant predictor of membership in the more active state. State did not predict BMI or weight percentile after adjusting for caloric intake.
Most children demonstrated high amounts of sedentary behavior, and rates of MVPA fell far below recommended levels for both states. The lack of statistically significant results for risk factors and PA state on weight-related outcomes is likely due to the homogeneous behaviors of the children.
Kelliann K. Davis, Deborah F. Tate, Wei Lang, Rebecca H. Neiberg, Kristen Polzien, Amy D. Rickman, Karen Erickson and John M. Jakicic
African-Americans lose less weight during a behavioral intervention compared with Whites, which may be from differences in dietary intake or physical activity.
Subjects (30% African American, 70% White; n = 346; 42.4 ± 9.0 yrs.; BMI = 33.0 ± 3.7 kg/m2) in an 18-month weight loss intervention were randomized to a standard behavioral (SBWI) or a stepped-care (STEP) intervention. Weight, dietary intake, self-report and objective physical activity, and fitness were assessed at 0, 6, 12, and 18 months.
Weight loss at 18 months was greater in Whites (–8.74 kg with 95% CI [–10.10, –7.35]) compared with African Americans (–5.62 kg with 95% CI [–7.86, –3.37]) (P = .03) in the SBWI group and the STEP group (White: –7.48 kg with 95% CI [–8.80, –6.17] vs. African American: –4.41kg with 95% CI [–6.41, –2.42]) (P = .01). Patterns of change in dietary intake were not different between groups. Objective physical activity (PA) changed over time (P < .0001) and was higher in Whites when compared with African Americans (P = .01).
Whites lost more weight (3.10 kg) than African American adults. Although there were no differences in dietary intake, Whites had higher levels of objective PA and fitness. Thus, the discrepancy in weight loss may be due to differences in PA rather than dietary intake. However, the precise role of these factors warrants further investigation.