Initial Body Mass Index and Free-Time Physical Activity Moderate Effects of the Youth Fit for Life Treatment in African-American Pre-Adolescents

In about 80% of youth obesity-prevention programs, significant decrease in Body Mass Index has not been observed. A meta-analysis of 16 trials of the 12-wk. Youth Fit For Life intervention suggested better success; however, the effects for children who were overweight or obese remain unclear because data from participants of all weights were aggregated. Also unclear were effects on increasing free-time physical activity, a goal of this and most obesity-prevention treatments. Of the 200 African American pre-adolescents assessed in the present investigation, reductions in Body Mass Index associated with Youth Fit For Life were larger for participants who were overweight and obese, but these two groups did not differ. Voluntary physical activity at baseline was inversely related to change in voluntary physical activity (r = –.53, p<.001). Regression analyses suggested improvements in theoretical dimensions of self-efficacy significantly predicted increases in voluntary physical activity especially well for participants initially classified as insufficiently active (R² = .61). These data clarified and extended findings to date for the Youth Fit For Life treatment, but replications across age groups, ethnicities, and administration formats are required.