Adolescents: A Test of the

The purpose of this study was to examine whether variables in the Transtheoretical Model (TTM) acted more as predictors than as consequences of exercise behav-ior (stage of change). Students from 13 New Zealand high schools (N = 1,434) completed questionnaires corresponding to variables in the TTM (i.e., stage of exercise change, processes of change, self-effi cacy, and decisional balance) at two time periods separated by 6 months. Reciprocal relationships were found between exercise behavior and the TTM variables. The TTM might be a useful framework for understanding longitudinal exercise behavior in the adolescent population. The benefi ts of regular physical activity for both adults (41) and younger people (36) are numerous. With respect to youth, evidence-based data are strong for benefi cial effects of physical activity to musculoskeletal health, cardiovascular health, and adiposity in the overweight (36). There is adequate research evidence supporting the benefi cial effects of physical activity on lipids and adiposity in normal-weight children and adolescents, cardiovascular variables, psychological factors, and academic performance (36)