Social-cognitive correlates of physical activity in a multi-ethnic cohort of middle-school girls: two-year prospective study

Description and evaluation of a social cognitive model of physical activity behaviour tailored for adolescent girls

The aim of this paper was to describe and test a social cognitive model of physical activity tailored for adolescent girls. Participants were 1518 girls (aged 13.6 ± 0.02 years) from 24 secondary schools in New South Wales, Australia. Useable accelerometer (≥10 hours day(-1) on at least 3 days) and questionnaire data were obtained from 68% of this sample (N = 1035). Participants completed questionnaires assessing psychological, behavioural, social and environmental correlates of activity. The theoretical model was tested using structural equation modelling in AMOS. The model explaining accelerometer counts per minute was an adequate-to-good fit to the data (Tucker-Lewis Index = 0.89, the comparative fit index = 0.97 and the root mean square of approximation = 0.098; 90% confidence interval = 0.075-0.122) but explained only 5% of the variance in activity. There were significant model pathways from self-efficacy (r = 0.11, P = 0.01), school environment (r = 0.07, P = 0.02) and physical self-worth (r = 0.07, P = 0.04) to accelerometer counts. Although the proposed model provided an adequate-to-good fit to the data, it explained a small portion of the variance. Shared method variance may explain the larger portions of variance explained in previous studies. Future studies are encouraged to evaluate theories of physical activity behaviour change using objective measures of physical activity.

Family- and school-based correlates of energy balance-related behaviours in 10-12-year-old children: a systematic review within the ENERGY (EuropeaN Energy balance Research to prevent excessive weight Gain among Youth) project

OBJECTIVE

To identify family- and school-based correlates of specific energy balance-related behaviours (physical activity, sedentary behaviour, breakfast consumption, soft drink consumption) among 10-12-year-olds, using the EnRG framework (Environmental Research framework for weight Gain prevention).

DESIGN

A literature review to identify observational studies exploring at least one family- or school-based correlate of the specific behaviours, resulting in seventy-six articles.

SETTING

Eighteen studies were conducted in Europe, forty-one studies in North America and seventeen studies in Australasia.

SUBJECTS

Healthy children aged 10-12 years.

RESULTS

Parental and maternal physical activity, doing physical activities with parents and parental logistic support were identified as the most important, positive correlates of physical activity. Parental rules was the most important correlate of sedentary behaviour and was inversely related to it. School socio-economic status was positively related to physical activity and inversely related to sedentary behaviour. The available studies suggested a positive relationship between soft drink availability at home and consumption. Soft drink availability and consumption at school were the most important school-based correlates of soft drink consumption. A permissive parenting style was related to more soft drink consumption and less breakfast consumption.

CONCLUSIONS

An important role has been awarded to parents, suggesting parents should be involved in obesity prevention programmes. Despite the opportunities a school can offer, little research has been done to identify school-environmental correlates of energy balance-related behaviours in this age group. Obesity prevention programmes can focus on the most important correlates to maximize the effectiveness of the programme. Future research should aim at longitudinal studies.

Predicting physical activity and fruit and vegetable intake in adolescents: a test of the information, motivation, behavioral skills model

Most adolescents do not meet national recommendations regarding physical activity and/or the intake of fruits and vegetables. The purpose of this study was to explore whether variables in the information, motivation, behavioral skills (IMB) model of health promotion predicted physical activity and fruit and vegetable intake in 404 adolescents from 2 high schools in the Southwest United States using structural equation modeling (SEM). The SEM models included theoretical constructs, contextual variables, and moderators. The theoretical relationships in the IMB model were confirmed and were moderated by gender and race. Interventions that incorporate cognitive-behavioral skills building may be a key factor for promoting physical activity as well as fruit and vegetable intake in adolescents.

Behavioral Self-Regulation and Weight-Related Behaviors in Inner-City Adolescents: A Model of Direct and Indirect Effects

BACKGROUND: This study examined the association of two distinct self-regulation constructs, effortful control and dysregulation, with weight-related behaviors in adolescents and tested whether these effects were mediated by self-efficacy variables. METHODS: A school-based survey was conducted with 1771 adolescents from 11 public schools in the Bronx, New York. Self-regulation was assessed by multiple indicators and defined as two latent constructs. Dependent variables included fruit/vegetable intake, intake of snack/junk food, frequency of physical activity, and time spent in sedentary behaviors. Structural equation modeling examined the relation of effortful control and dysregulation to lifestyle behaviors, with self-efficacy variables as possible mediators. RESULTS: Study results showed that effortful control had a positive indirect effect on fruit and vegetable intake, mediated by self-efficacy, as well as a direct effect. Effortful control also had a positive indirect effect on physical activity, mediated by self-efficacy. Dysregulation had direct effects on intake of junk food/snacks and time spent in sedentary behaviors. CONCLUSIONS: These findings indicate that self-regulation characteristics are related to diet and physical activity and that some of these effects are mediated by self-efficacy. Different effects were noted for the two domains of self-regulation. Prevention researchers should consider including self-regulation processes in programs to improve health behaviors in adolescents.

Physical activity interventions and children's mental function: an introduction and overview

BACKGROUND

This review provides a historical overview of physical activity interventions designed by American educators and an evaluation of research that has assessed the effects of exercise on children's mental function.

METHOD

Historical descriptions of the emergence of American physical education doctrine throughout the 20th century were evaluated. Prior reviews of studies that assessed the effects of single acute bouts of exercise and the effects of chronic exercise training on children's mental function were examined and the results of recent studies were summarized.

RESULTS

Physical activity interventions designed for American children have reflected two competing views: activities should promote physical fitness and activities should promote social, emotional, and intellectual development. Research results indicate that exercise fosters the emergence of children's mental function; particularly executive functioning. The route by which physical activity impacts mental functioning is complex and is likely moderated by several variables, including physical fitness level, health status, and numerous psycho-social factors.

CONCLUSION

Physical activity interventions for children should be designed to meet multiple objectives; e.g., optimize physical fitness, promote health-related behaviors that offset obesity, and facilitate mental development.

Adolescents' attitudes toward sports, exercise, and fitness predict physical activity 5 and 10 years later

OBJECTIVE

To determine whether adolescent attitudes towards sports, exercise, and fitness predict moderate-to-vigorous physical activity 5 and 10 years later.

METHOD

A diverse group of 1902 adolescents participating in Project Eating and Activity in Teens, reported weekly moderate-to-vigorous physical activity and attitudes toward sports, exercise, and fitness in Eating and Activity in Teens-I (1998-99), Eating and Activity in Teens-II (2003-04), and Eating and Activity in Teens-III (2008-09).

RESULTS

Mean moderate-to-vigorous physical activity was 6.4, 5.1, and 4.0 hours/week at baseline, 5-year, and 10-year follow-up, respectively. Attitudes toward sports, exercise, and fitness together predicted moderate-to-vigorous physical activity at 5 and 10 years. Among the predictors of 5- and 10-year moderate-to-vigorous physical activity, attitude's effect size, though modest, was comparable to the effect sizes for sports participation and body mass index. Adolescents with more-favorable attitudes toward sports, exercise, and fitness engaged in approximately 30%-40% more weekly moderate-to-vigorous physical activity at follow-up (2.1 hour/week at 5 years and 1.2 hour/week at 10 years) than those with less-favorable attitudes.

CONCLUSION

Adolescents' exercise-related attitudes predict subsequent moderate-to-vigorous physical activity independent of baseline behavior suggesting that youth moderate-to-vigorous physical activity promotion efforts may provide long-term benefits by helping youth develop favorable exercise attitudes.

Adolescents' sports and exercise environments in a U.S. time use survey

BACKGROUND

Studies examining environmental influences on adolescent physical activity largely measure the presence and availability of social resources and built environment facilities. Unfortunately, this research approach provides limited information about adolescents' social company during exercise or the extent to which adolescents actually use physical settings for physical activity.

PURPOSE

The current study used data from the nationally representative American Time Use Survey (2003-2006) to describe demographic and temporal patterns in the social and physical contexts of physical activity among adolescents.

METHODS

The sample consisted of high school students (aged 15-18 years) reporting at least one bout of sports or exercise (N=867). During the interview, participants reported where (e.g., outdoors, home, work) and with whom (e.g., alone, family, friends) each bout occurred. Sample-weighted multinomial logistic regression analyses compared the proportion of bouts occurring in each environment by age, gender, family income, season, weekend/weekday, and time of day, controlling for race/ethnicity. Data were analyzed in 2009.

RESULTS

Girls were more likely to exercise with family (22% vs 16%), and less likely to exercise with friends/acquaintances/others (47% vs 52%) and outdoors (18% vs 24%) than boys. Compared with those aged 15 years, a larger proportion of exercise bouts among those aged 18 years occurred alone (23% vs 18%); and a smaller proportion occurred at home (14% vs 20%), at someone else's house (5% vs 12%), and at school (14% vs 27%) (p's<0.001).

CONCLUSIONS

Information about the social and physical contexts of adolescents' sports and exercise can help guide the selection of future environmental targets for investigation and intervention.

Validity of social-cognitive measures for physical activity in middle-school girls

OBJECTIVE

The factorial validity and measurement equivalence/invariance of scales used to measure social-cognitive correlates of physical activity among adolescent girls were examined.

METHODS

Confirmatory factor analysis was applied to questionnaire responses obtained from a multi-ethnic sample (N = 4885) of middle-school girls from six regions of the United States. A cohort of 1893 girls completed the scales in both sixth and eighth grades, allowing longitudinal analysis.

RESULTS

Theoretically and statistically sound models were developed for each scale, supporting the factorial validity of the scales in all groups. Multi-group and longitudinal invariance was confirmed across race/ethnicity groups, age within grade, BMI categories, and the 2-year period between grades.

CONCLUSIONS

The scores from the scales provide valid assessments of social-cognitive variables that are putative mediators or moderators of change in physical activity. The revised scales can be used in observational studies of change or interventions designed to increase physical activity among girls during early adolescence.

Self-efficacy moderates the relation between declines in physical activity and perceived social support in high school girls

OBJECTIVE

To test whether self-efficacy for overcoming barriers to physical activity has direct, indirect (i.e., mediated), or moderating relations with naturally occurring change in perceived social support and declines in physical activity during high school.

METHODS

Latent growth modeling was used with measures completed in the 8th, 9th, and 12th grades by a cohort of 195 Black and White girls.

RESULTS

Self-efficacy was stable and moderated the relation between changes in physical activity and perceived social support. Girls who maintained a perception of strong social support had less of a decline in physical activity if they also had high self-efficacy. However, girls having high self-efficacy had a greater decline in physical activity if they perceived declines in social support.

CONCLUSIONS

Randomized controlled trials of physical activity interventions based on social cognitive theory should consider that the influence of girls' perceptions of social support on their physical activity may differ according to their efficacy beliefs about barriers to physical activity.