Nandini Karunamuni

Social cognitive theories used to explain physical activity behavior in adolescents: a systematic review and meta-analysis

PURPOSE To systematically review and examine the explanatory power of key social-cognitive theories used to explain physical activity (PA) intention and behavior, among adolescents. METHODS A systematic review and meta-analysis of the literature was performed using the electronic databases Medline, Cumulative Index to Nursing and Allied Health Literature, SPORTdiscus, EBSCO and Education Resources Information Center, Proquest Education Journals Collection, Science Direct, Web of Science and Scopus for social-cognitive theories (i.e., Health Promotion Model, Theory of Planned Behavior, Theory of Reasoned Action, Protection Motivation Theory, Social Cognitive Theory/Self-Efficacy Theory, Health Belief Model, Self-Determination Theory, Transtheoretical Model) used to explain PA intention and behavior. Related keywords in titles, abstracts, or indexing fields were searched. RESULTS Twenty-three studies satisfied the inclusion criteria and were retained for data extraction and analysis; 16 were cross-sectional studies and seven were longitudinal studies. Most studies employed self-report measures. In general, the models explained greater proportions of variance for intention compared to behavior. The meta-analyses revealed 33% and 48% of the variance respectively for PA and intention were explained by social cognitive models. CONCLUSIONS Few studies have tested the predictive capacity of social cognitive theories to explain objectively measured PA. The majority of PA variance remains unexplained and more theoretical research is needed.

Chronic Disease–Related Lifestyle Risk Factors in a Sample of Canadian Adolescents

This study examined the prevalence, clustering, age trends, and gender differences of chronic-disease related risk factors among a large sample of adolescents (N = 4932) in Alberta, Canada. Approximately 43% of boys and 53% of girls displayed two or more risk factors. Age trends and gender differences were also observed.

Aerobic physical activity and resistance training: an application of the theory of planned behavior among adults with type 2 diabetes in a random, national sample of Canadians

BackgroundAerobic physical activity (PA) and resistance training are paramount in the treatment and management of type 2 diabetes (T2D), but few studies have examined the determinants of both types of exercise in the same sample.ObjectiveThe primary purpose was to investigate the utility of the Theory of Planned Behavior (TPB) in explaining aerobic PA and resistance training in a population sample of T2D adults.MethodsA total of 244 individuals were recruited through a random national sample which was created by generating a random list of household phone numbers. The list was proportionate to the actual number of household telephone numbers for each Canadian province (with the exception of Quebec). These individuals completed self-report TPB constructs of attitude, subjective norm, perceived behavioral control and intention, and a 3-month follow-up that assessed aerobic PA and resistance training.ResultsTPB explained 10% and 8% of the variance respectively for aerobic PA and resistance training; and accounted for 39% and 45% of the variance respectively for aerobic PA and resistance training intentions.ConclusionThese results may guide the development of appropriate PA interventions for aerobic PA and resistance training based on the TPB.

Community-based physical activity interventions for treatment of type 2 diabetes: a systematic review with meta-analysis.

Evidence suggests engaging in regular physical activity (PA) can have beneficial outcomes for adults with type 2 diabetes (TD2), including weight loss, reduction of medication usage and improvements in hemoglobin A1c (HbA1c)/fasting glucose. While a number of clinical-based PA interventions exist, community-based approaches are limited. The objective of this study is to conduct a systematic review with meta-analysis to assess the effectiveness of community-based PA interventions for the treatment of TD2 in adult populations. A search of peer-reviewed publications from 2002 to June 2012 was conducted across several electronic databases to identify interventions evaluated in community settings. Twenty-two studies were identified, and 11 studies reporting HbA1c as an outcome measure were pooled in the meta-analysis. Risk of bias assessment was also conducted. The findings demonstrate community-based PA interventions can be effective in producing increases in PA. Meta-analysis revealed a lowering of HbA1c levels by −0.32% [95% CI −0.65, 0.01], which approached statistical significance (p < 0.06). Our findings can guide future PA community-based interventions in adult populations diagnosed with TD2.

Assessing the Validity of a Stage Measure on Physical Activity in a Population-Based Sample of Individuals With Type 1 or Type 2 Diabetes

This study was designed to test the validity of a transtheoretical models physical activity (PA) stage measure with intention and different intensities of behavior in a large population-based sample of adults living with diabetes (Type 1 diabetes, n = 697; Type 2 diabetes, n = 1,614) and examine different age groups. The overall specificity (classified correctly as inactive) for Type 1 diabetes was 69.3% based on the percentage of individuals in precontemplation, contemplation, and preparation not meeting Canadas PA guidelines. Sensitivity (classified correctly as active) was 82.5% based on the proportion of active participants in action and maintenance. In the Type 2 diabetes group, the overall specificity and sensitivity was 63.9% and 88.2%, respectively. No significant differences were found between the diabetes groups for stage distribution patterns, and sensitivity and specificity values. The majority of the study hypotheses related to intention and behaviors were confirmed, providing further supportive evidence for the utility of this PA staging measure for the diabetes population.

Reducing Sitting Time: The New Workplace Health Priority

Mechanization and automation of society have resulted in significantly reduced demands for physical activity in the population. Since the middle of the last century, sedentary behavior pursuits suc...

Multicomponent, home-based resistance training for obese adults with type 2 diabetes: a randomized controlled trial

Purpose:To investigate whether a home-based resistance training (RT) program that supplied high-quality equipment and qualified exercise specialists could provide benefits to obese patients with type 2 diabetes.Methods:A total of 48 obese individuals with type 2 diabetes were randomly assigned to either an RT (n=27) or a control group (n=21). Those in the RT group received a multigym and dumbbells and performed RT 3 days per week for 16 weeks at home. A qualified exercise specialist supervised training, with supervision being gradually decreased throughout the study. Primary outcome measures included strength and hemoglobin-A1C, whereas secondary outcome measures included other cardiovascular risk markers, key social-cognitive constructs and health-related quality of life.Results:Intention-to-treat analyses indicated a significant increase in upper and lower body strength for the RT group compared with controls (20–37% mean increases in the RT group). No significant reduction in A1C levels was observed. The RT group had unchanged high-density lipoprotein cholesterol levels in comparison to declines in the control group. Significant reductions in fasting insulin, and increases in RT-related self-efficacy and intentions, were also observed in the RT group.Conclusions:Supervised home-based RT with high-quality equipment was effective for improving strength, along with other secondary outcomes in obese patients with type 2 diabetes.

Predictors of physical activity in adults with type 2 diabetes

OBJECTIVES To determine demographic, medical, social cognitive, and environmental predictors of aerobic physical activity and resistance training in a population sample of adults with type 2 diabetes. METHODS Two hundred forty-four (244) participants completed questionnaires with a 3-month follow-up. Multiple and logistic regression models examined predictors of aerobic activity and resistance training. RESULTS Several factors were associated with higher levels of both aerobic physical activity and resistance training; self-efficacy was the strongest predictor for both modes of activity. CONCLUSIONS The findings can guide physical activity promotion interventions and programs for this population, profiling those who are least active.

Knowledge, attitudes and behaviours related to climate change in Alberta, Canada: implications for public health policy and practice

Climate change has received recent extensive media attention (e.g., Kyoto Protocol) and is currently on the international public health agenda. The purpose of this study was to survey knowledge, attitudes and behaviours related to climate change in the province of Alberta, Canada. A random sample of 600 Alberta households, using proportional quotas based on the Canada Census of the Alberta population, was surveyed on knowledge, attitudes and behaviours related to climate change using a computer-assisted telephone interviewing protocol. Albertans are highly concerned, particularly about health problems related to the environment and air pollution; yet are only moderately informed about a variety of environmental issues. While the great majority of Albertans appear to be engaged in environmental behaviours at home, fewer consider energy efficiency when purchasing consumer goods. An even smaller percentage makes environmentally conscious transportation decisions. To encourage the population to make recommended environmental behaviours, mass media approaches may do well to target the specific beliefs that were deemed salient (e.g., promote the association between environment issues and health). The public health sector has a major role in working with inter-sectoral groups to address this significant public health issue.

Population-Based Estimates of Physical Activity for Adults with Type 2 Diabetes: A Cautionary Tale of Potential Confounding by Weight Status

At a population level, the method used to determine those meeting physical activity guidelines has important implications, as estimating “sufficient” physical activity might be confounded by weight status. The objective of this study was to test the difference between three methods in estimating the prevalence of “sufficient activity” among Canadian adults with type 2 diabetes in a large population sample (N = 1614) while considering the role of weight status as a potential confounder. Our results revealed that estimates of physical activity levels vary by BMI categories, depending on the methods examined. Although physical activity levels were lower in the obese, their energy expenditure estimates were not different from those who were overweight or of a healthy weight. The implications of these findings are that biased estimates of physical activity at a population level may result in inappropriate classification of adults with type 2 diabetes as “sufficiently active” and that the inclusion of body weight in estimating physical activity prevalence should be approached with caution.