Background: This study aimed to examine the factor structure of responses to the Portuguese version of questions related to screen time–based sedentary behavior among adolescents. Methods: This cross-sectional study with a sample of 1083 adolescents aged 14–19 years was conducted in Brazil. The sample was randomly divided into 2 groups for an exploratory factor analysis and for a confirmatory factor analysis. Screen time was investigated by a Portuguese version of questions about time sitting in front of television, computer, and video games on weekdays and weekends. Results: Scree plots showed 2 factors with eigenvalues above 1. One factor was formed by items about television and computer use, and the other factor was formed by items about video game use. The exploratory factor analysis with 2 factors resulted in factor loadings above .60. A second model with 1 factor was estimated and resulted in factor loadings above .55. A confirmatory factor analysis was estimated based on the 2-factor exploratory factor analysis and goodness-of-fit statistics were adequate. Confirmatory factor analysis with 1 factor had goodness-of-fit statistics adequate. Conclusions: The Portuguese language version of self-report screen time had 2 possible factor solutions, and items demonstrated good factor structure with reasonable reliability making it suitable for use in the future studies.
Diego Augusto Santos Silva, Katie E. Gunnell and Mark Stephen Tremblay
Katie E. Gunnell, Jennifer Brunet, Erin K. Wing and Mathieu Bélanger
Perceived barriers to moderate-to-vigorous physical activity (PA) may contribute to the low rates of moderate-to-vigorous PA in adolescents. We examined the psychometric properties of scores from the perceived barriers to moderate-to-vigorous PA scale (PB-MVPA) by examining composite reliability and validity evidence based on the internal structure of the PB-MVPA and relations with other variables.
This study was a cross-sectional analysis of data collected in 2013 from adolescents (N = 507; M age = 12.40, SD = .62) via self-report scales.
Using exploratory and confirmatory factor analyses, we found that perceived barriers were best represented as two factors representing internal (e.g., “I am not interested in physical activity”) and external (e.g., “I need equipment I don’t have”) dimensions. Composite reliability was over .80. Using multiple regression to examine the relationship between perceived barriers and moderate-to-vigorous PA, we found that perceived internal barriers were inversely related to moderate-to-vigorous PA (β = -.32, p < .05). Based on results of the analysis of variances, there were no known-group sex differences for perceived internal and external barriers (p < .26).
The PB-MVPA scale demonstrated evidence of score reliability and validity. To improve the understanding of the impact of perceived barriers on moderate-to-vigorous PA in adolescents, researchers should examine internal and external barriers separately.
Katie E. Gunnell, Jennifer Brunet, Catherine Sabiston and Mathieu Bélanger
Despite research attention toward understanding relationships between psychological need satisfaction (PNS), moderate-to-vigorous-intensity physical activity (MVPA), and health-related quality of life (HRQoL), methodological limitations make it difficult to establish reciprocal and mediating effects. Reciprocal relationships between PNS and MVPA were examined over 4 years, and their effects on adolescents’ change in dimensions of HRQoL were examined. Self-reported data were collected from 932 adolescents (M age = 10.9 years) every 4 months beginning in Grades 5/6. At the between-persons and within-person level, earlier PNS predicted later MVPA whereas earlier MVPA did not predict later PNS. Increases in MVPA were associated with greater change in physical (βlinear = .61, βquadratic = .77, ps = .03) and school functioning (βlinear = .68, βquadratic = .84, ps = .03) but no other dimensions of HRQoL (p > .05). Decreases in PNS were not associated with any of the dimensions of HRQoL. Fostering adolescents’ PNS could be a starting point to increase MVPA, which, in turn, may enhance select dimensions of HRQoL.
Diane E. Mack, Philip M. Wilson, Virginia Lightheart, Kristin Oster and Katie E. Gunnell
The primary purpose of this investigation was to examine the frequency and type of self-reported physical activity behavior in postsecondary students with reference to Healthy Campus 2010 objectives. The secondary purpose was to explore the role of information provision in terms of promoting physical activity behavior in postsecondary students.
Postsecondary students were assessed (N = 127360). Employing a trend survey design, the frequency and type of physical activity behavior was assessed along with physical activity/fitness information provision across a five year period between 2000 to 2004.
In 2004, respondents meeting Healthy Campus 2010 objectives for self-reported moderate and vigorous physical activity (MVPA) was 42.20% (95% CI = 41.75 to 42.65) and 48.60% (95% CI = 48.14 to 49.06) for strength (STRENGTH) training behavior. Progress quotients demonstrated that 12.93% and 7.87% of target objective for MVPA and STRENGTH respectively had been achieved from baseline. Those who received information reported engaging in more frequent physical activity behavior compared with those who did not (P < .001).
Results suggest the need for continued commitment to increasing physical activity behavior. The provision of physical activity/fitness information may be one mechanism through which this can be achieved.
Jennifer Brunet, Katie E. Gunnell, Pedro Teixeira, Catherine M. Sabiston and Mathieu Bélanger
The objectives of this study were to examine whether (a) measures designed to assess satisfaction of competence, autonomy, and relatedness needs in physical activity contexts can represent both general and specific needs satisfaction and (b) the specific needs are associated with concurrent moderate-to-vigorous-intensity physical activity (MVPA) participation (Time 1) and MVPA participation 4 months later (Time 2), beyond general psychological need satisfaction (PNS). Data from 544 adolescents (M age = 14.1 years, SD = 0.6) were analyzed. A bifactor model specifying four factors (i.e., one general PNS and three specific needs) provided a good fit to the data. Extending the model to predict Time 1 and Time 2 MVPA participation also provided a good fit to the data. General PNS and specific needs had unique and empirically distinguishable associations with MVPA participation. The bifactor operationalization of PNS provides a framework to delineate common and distinctive antecedents and outcomes of general PNS and specific needs.