Background/Purpose: It has been evident that there is a dramatic decline in participation in physical activity for adolescent girls (Pratt et al., 1999). It is therefore important to understand the specific reasons adolescent girls are reluctant to be physically active. Using Social cognitive theory (Bandura, 1997) as a theoretical framework, this study was designed to examine the relationships between adolescent girls' exercise motivation and physical activity participation.
Methods: Participants were 92 sixth through ninth grade girls (Mage =12±.63; 52% African Americans, 21% Latinos) recruited from four urban schools at Southwest region. All girls' exercise motivation (self-efficacy, outcome expectancy and social support) was measured at baseline in fall of 2008, and was used to predict their 3-day daily physical activity levels as measured by W4L Neo II pedometers one week thereafter. Girls' mean steps per day and mean time spent in moderate to vigorous physical activity (MVPA) per day were used as the outcome variables.
Analysis/Results: Girls' self-efficacy was positively related to their mean steps and mean time in MVPA (r = .36 - .38; p < .01). Regression analyses further yielded that girls' self-efficacy emerged as the sole predictor of their mean steps (b = .36, p < .01) and mean time in MVPA (b = .38, p < .01). However, girls' outcome expectancy and social support failed to predict physical activity participation.
Conclusions: Adolescent girls' self-efficacy appeared as the only predictor of their daily physical activity participation, and therefore interventions to enhance their self-efficacy should be considered.