Johan Y. Y. Ng

Self-Determination Theory Applied to Health Contexts: A Meta-Analysis.

Behavior change is more effective and lasting when patients are autonomously motivated. To examine this idea, we identified 184 independent data sets from studies that utilized self-determination theory (SDT; Deci & Ryan, 2000) in health care and health promotion contexts. A meta-analysis evaluated relations between the SDT-based constructs of practitioner support for patient autonomy and patients’ experience of psychological need satisfaction, as well as relations between these SDT constructs and indices of mental and physical health. Results showed the expected relations among the SDT variables, as well as positive relations of psychological need satisfaction and autonomous motivation to beneficial health outcomes. Several variables (e.g., participants’ age, study design) were tested as potential moderators when effect sizes were heterogeneous. Finally, we used path analyses of the meta-analyzed correlations to test the interrelations among the SDT variables. Results suggested that SDT is a viable conceptual framework to study antecedents and outcomes of motivation for health-related behaviors.

Personal and psychosocial predictors of doping use in physical activity settings: a meta-analysis.

BackgroundThere is a growing body of empirical evidence on demographic and psychosocial predictors of doping intentions and behaviors utilizing a variety of variables and conceptual models. However, to date there has been no attempt to quantitatively synthesize the available evidence and identify the strongest predictors of doping.ObjectivesUsing meta-analysis, we aimed to (i) determine effect sizes of psychological (e.g. attitudes) and social-contextual factors (e.g. social norms), and demographic (e.g. sex and age) variables on doping intentions and use; (ii) examine variables that moderate such effect sizes; and (iii) test a path analysis model, using the meta-analyzed effect sizes, based on variables from the theory of planned behavior (TPB).Data SourcesArticles were identified from online databases, by contacting experts in the field, and searching the World Anti-Doping Agency website.Study Eligibility Criteria and ParticipantsStudies that measured doping behaviors and/or doping intentions, and at least one other demographic, psychological, or social-contextual variable were included. We identified 63 independent datasets.Study Appraisal and Synthesis MethodStudy information was extracted by using predefined data fields and taking into account study quality indicators. A random effects meta-analysis was carried out, correcting for sampling and measurement error, and identifying moderator variables. Path analysis was conducted on a subset of studies that utilized the TPB.ResultsUse of legal supplements, perceived social norms, and positive attitudes towards doping were the strongest positive correlates of doping intentions and behaviors. In contrast, morality and self-efficacy to refrain from doping had the strongest negative association with doping intentions and behaviors. Furthermore, path analysis suggested that attitudes, perceived norms, and self-efficacy to refrain from doping predicted intentions to dope and, indirectly, doping behaviors.LimitationsVarious meta-analyzed effect sizes were based on a small number of studies, which were correlational in nature. This is a limitation of the extant literature.ConclusionsThis review identifies a number of important correlates of doping intention and behavior, many of which were measured via self-reports and were drawn from an extended TPB framework. Future research might benefit from embracing other conceptual models of doping behavior and adopting experimental methodologies that will test some of the identified correlates in an effort to develop targeted anti-doping policies and programs.

Self-determined motivation and physical activity in children and adolescents : A systematic review and meta-analysis

OBJECTIVE Self-determination theory is used as a framework for examining the relation between motivation and physical activity. The purpose of this review was to systematically review studies that assessed the association between self-determined motivation and physical activity levels in children and adolescents. METHOD We searched electronic databases in April 2013. Included studies assessed the relation between motivation (as outlined in self-determination theory) and physical activity in children and adolescents. RESULTS Forty-six studies (n=15,984 participants) met the inclusion criteria. Meta-analysis indicated that overall levels of self-determined motivation had a weak to moderate, positive associations with physical activity (ρ=.21 to .31). Autonomous forms of motivation (i.e., intrinsic motivation and identified regulation) had moderate, positive associations with physical activity (ρ=.27 to .38), whereas controlled forms of motivation (i.e., introjection and external regulation) had weak, negative associations with physical activity (ρ=-.03 to -.17). Amotivation had a weak, negative association with physical activity (ρ=-.11 to -.21). CONCLUSIONS Evidence provides some support for self-determination theory tenets. However, there was substantial heterogeneity in most associations and many studies had methodological shortcomings.

Predicting Psychological Needs and Well-Being of Individuals Engaging in Weight Management: The Role of Important Others

BACKGROUND Using the self-determination theory (SDT) framework, we examined how significant others might support or thwart psychological needs of people with weight management goals, and in turn might affect their psychological well-being and weight control behaviors. DESIGN Longitudinal design with three sets of questionnaires administered over a 6-month period. METHODS One hundred and fifty-six eligible participants (age = 31.01 ± 13.21 years) were asked to complete questionnaires of SDT-based constructs, weight management behaviors, and psychological well-being. Hypotheses were tested using Bayesian path analysis. RESULTS Perceived autonomy support from significant others was related to psychological need satisfaction, while controlling behaviors by others were associated with need thwarting. In turn, need satisfaction was associated with some beneficial outcomes such as life satisfaction, and need thwarting was related to some maladaptive outcomes such as higher levels of depressive symptoms and increases in unhealthy diet behaviors. CONCLUSIONS Our findings indicate that the quality of interactions between individuals engaged in weight management and their significant others matters in terms of predicting the psychological needs and well-being of the former.

Outcomes of the Rope Skipping ‘STAR’ Programme for Schoolchildren

Abstract Physical activity in children and adolescents is on a decline trend. To this end, we conducted a matched-pair randomized controlled trial to examine the effects of a 4-week STAR (School-based; Train-the-trainer; Accessibility of resources; Recreational) skipping programme. 1,386 schoolchildren from 20 primary and secondary schools were recruited. Schools were randomized into the experimental or wait-list control group. Participants self-reported their health-related quality of life using the KIDSCREEN-27. Accelerometers were used to measure the time a subgroup of participants (n = 480) spent in moderate-to-vigorous physical activity during school hours on five consecutive days. Measures were taken at pre- and post-test. At post-test, students in the experimental group, compared to those in the control group, engaged in less moderate-to-vigorous physical activity during school hours. Health-related quality of life from two groups of students was similar, but the experimental group reported higher levels of autonomy and parent relationships. Results suggested that although the intervention did not increase students’ physical activity levels, it slightly improved their health-related quality of life. Future studies should explore personal factors that might mediate the effect of the intervention.

A school-based rope skipping intervention for adolescents in Hong Kong: protocol of a matched-pair cluster randomized controlled trial.

BackgroundSchools present venues for physical activity promotion among youth, with physical education (PE) considered the primary vehicle responsible for increasing activity levels. Yet students are not very physically active during typical school PE classes. With the aim to engage Hong Kong students in more moderate-to-vigorous physical activity (MVPA) during PE, a fitness infusion intervention using rope skipping was designed, and its effectiveness will be examined. Rope skipping was chosen because a) it provides moderate-to-high intensity physical activity; b) is inexpensive; c) students find it enjoyable; and d) is feasible in typical environments in Hong Kong, where PE classes are large in size (up to 40 students) and space available for physical activity is usually limited.Methods/DesignA matched-pair cluster randomized controlled trial was designed. Secondary school students from 24 classes (from 12 schools) will be recruited to participate in the trial. Students’ baseline MVPA will be measured during school PE. Classes will be matched according to baseline variables and one class from each pair will be randomized into the experimental group. Teachers in the experimental group will be invited to attend a teacher workshop, and will insert a 15-minute rope skipping activity in four consecutive PE lessons. Motivational factors based on self-determination theory will also be measured as secondary outcomes. The effectiveness of the intervention will be evaluated by comparing changes in the proportion of lesson time spent in MVPA from baseline to follow-up across the experimental and control groups.DiscussionPhysical activity levels in PE are often very low and there is a need to identify feasible low-cost interventions that can be easily disseminated. If the results of the study suggest the intervention to be effective, it could be implemented to schools throughout Hong Kong and other cities where space is limited.Trail registrationANZCTR: ACTRN12613000968774. Registered on 30 August 2013.

Psychometric properties of the Chinese (Cantonese) versions of the KIDSCREEN health-related quality of life questionnaire

AbstractPurposeThe KIDSCREEN questionnaire assesses health-related quality of life in children and adolescents. In this study, the questionnaire was translated into Chinese (Cantonese) and administered to two independent groups of Hong Kong Chinese students. Various aspects of reliability and validity of the KIDSCREEN-52 and KIDSCREEN-27 questionnaires were examined.Methods The translated KIDSCREEN-52 questionnaire (and thus the KIDSCREEN-27 as a subset of the long form) was administered to cohorts of 1379 and 555 students. Confirmatory factor analysis and partial credit Rasch analyses were used to examine the underlying structure of the instrument. Test–retest reliability, convergent, and divergent validity were also examined.ResultsThe 10-factor structure of the Chinese KIDSCREEN-52 was supported. However, the original five-factor model of the KIDSCREEN-27 was not supported as seven distinct factors were found. Internal consistency and test–retest reliability were acceptable. Evidence supporting convergent and divergent validity was found.ConclusionsResults from the two studies supported the use of the translated Chinese version of KIDSCREEN questionnaire children and adolescents’ health-related quality of life. Further research is required to examine possible cultural or language differences between the original version and the translated Chinese version of the questionnaire.

Autonomous Motivation Predicts 7-Day Physical Activity in Hong Kong Students.

Autonomous motivation predicts positive health behaviors such as physical activity. However, few studies have examined the relation between motivational regulations and objectively measured physical activity and sedentary behaviors. Thus, we investigated whether different motivational regulations (autonomous motivation, controlled motivation, and amotivation) predicted 7-day physical activity, sedentary behaviors, and health-related quality of life (HRQoL) of students. A total of 115 students (mean age = 11.6 years, 55.7% female) self-reported their motivational regulations and health-related quality of life. Physical activity and sedentary behaviors were measured using accelerometers for seven days. Using multilevel modeling, we found that autonomous motivation predicted higher levels of moderate-to-vigorous physical activity, less sedentary behaviors, and better HRQoL. Controlled motivation and amotivation each only negatively predicted one facet of HRQoL. Results suggested that autonomous motivation could be an important predictor of physical activity behaviors in Hong Kong students. Promotion of this form of motivational regulation may also increase HRQoL.

Associations between fundamental movement skill competence, physical activity and psycho-social determinants in Hong Kong Chinese children

ABSTRACT Associations between fundamental movement skills (FMS), perceived competence, enjoyment and physical activity (PA) have not been widely investigated among Chinese school children. We hypothesised that FMS would be directly related to self-reported and objectively measured PA, and indirectly related to these outcomes via perceived physical and movement skill competence, and enjoyment. Participants were 763 primary school children (age = 9.3 ± 1.7 years; 474 girls) across grades. FMS were measured for a subsample (n = 603) using Test of Gross Motor Development-2. PA using accelerometers was obtained from this subgroup (n = 238). All participating children completed a questionnaire measuring their PA participation, enjoyment, and perceived physical and movement skill competence. Structural equation modelling revealed positive associations between locomotor skills and perceived movement skill competence (β = .11, 95% CI [.001, .22]), and between perceived movement skill competence and objectively measured PA (β = .59, 95% CI [.04, 1.14]). Perceived physical competence and enjoyment mediated the association between locomotor skills and self-reported PA (β = .08, 95% CI [.02, .12]), but not objectively measured PA. Given inconsistent findings for subjective and objective measures of PA, further mediation analyses of the association between FMS and PA may be warranted.

Rope skipping increases bone mineral density at calcanei of pubertal girls in Hong Kong: A quasi-experimental investigation

Bone mineral accrual during puberty is important, especially in girls, because it is related to reduced risks of osteoporosis in adulthood. Previous research has shown that jumping or plyometric exercises may be effective in increasing bone mineral density in adolescents. Rope skipping is a form of activity that involves jumping, thus regular skipping may also increase bone mineral density in pubertal girls. To this end, we conducted a quasi-experimental to examine the effects of rope skipping on girls’ bone mineral density and cardiovascular fitness. 176 Hong Kong girls (age = 12.23 ± 1.80 years at baseline) were recruited to take part in the study. Bone density at their forearms and calcanei were measured twice over two academic years (mean time between visits was 10.3 months). Using multilevel modeling analyses and adjusting for participants’ height and physical activity, we found that girls who participated in weekly rope skipping activities, compared to those who did not, had higher levels of bone density at the calcanei (B = 0.023, p < .01). However, no differences were found for bone density at forearms or participants’ cardiovascular fitness. The rates of change of these variables across time were also not significantly different. Results suggest that regular rope skipping may increase girls’ bone density at the lower extremities, irrespective of the amount of self-report physical activity. However, further research is required to examine the potential dose-response relation between skipping behaviors and the measured outcomes.