Cardiovascular disease is currently the leading cause of death in Canada and other developed countries. Physical activity based cardiac rehabilitation programs have been shown to reduce the likelihood of subsequent cardiac events and even reverse the disease process. However, factors influencing physical activity in cardiac patients are still not clearly understood. The overall objective of this dissertation was therefore to better understand motivation and physical activity in a cardiac rehabilitation context. Specifically, theory-based motivational variables were studied as correlates of physical activity. To accomplish this objective, a two-purpose research approach was taken. First, two articles (Article-1 and Article-2) aimed to test and integrate concepts from two strong motivational theories: Self-Efficacy Theory (SET) and Self-Determination Theory (SDT) into one comprehensive model using the novel and rigorous approach of Noar and Zimmerman (2005). The second purpose of this dissertation was to extend the findings from the first purpose by investigating physical activity and motivational patterns over a 24-month period in cardiac patients (Article 3). With regards to the first purpose, Article-1 revealed that the integration of SDT and SET was feasible as the integrated model had good model fit, explained more variance in self-determined motivation, confidence, and physical activity and supported similar number of hypothesised links in a cross-sectional cardiac sample as well two other samples: primary care adults and university students. Due to the cross-sectional nature of Article-1, Article-2 tested the integrated SDT-SET model from cardiac patients with longitudinal data of patients following a cardiac rehabilitation program. Although no motivational variables predicted residual change in physical activity at 4-months, this longitudinal model was found to have good model fit. Across both articles, the integration of SDT and SET was found to be possible. However, more research is needed to further test the integration of these theories. As for the second purpose of this dissertation, Article-3 investigated physical activity and motivational patterns of cardiac rehabilitation participants over the course of 24 months. Distinct patterns were found for physical activity, self-determined motivation, barrier self-efficacy and outcome expectations. In addition, individuals in the higher patterns of the motivational/expectancy variables had greater probability of being in the maintenance physical activity pattern compared to individuals in the other motivational/expectancy patterns. Therefore, this article extended findings from the first purpose by linking SDT and SET variables to long-term physical activity behaviour. SDT and SET should continue to be investigated together in order to increase our understanding of the mechanisms leading to greater motivation and subsequent increases in physical activity levels. Having a theoretically supported pathway to build motivation is ideal to inform future interventions and cardiac rehabilitation programs.

This thesis, comprising two studies, investigated whether negative expectations and self-perceptions relating to the aging process are associated with less physical activity (Study 1), and whether less active adults are likely to report age as a cause for physical activity failure than more active adults (Study 2). Using Sarkisian et al.’s (2002) Expectations Regarding Aging (ERA-38) survey, Study 1 first developed reliable and valid sub-factors for constructs relating to general aging expectations (GAE) and aging self-perceptions (ASP) by conducting exploratory factor analyses on 167 adults (M age = 59.5). Results revealed three acceptable GAE sub-factors relating to satisfaction/contentment, physical function and cognitive function, and three ASP sub-factors pertaining to functional, social, and sexual health. Subsequent MANOVA analyses showed that active adults reported higher GAE for satisfaction/contentment and cognitive function than less active adults. Regression analyses revealed that physical activity levels positively predicted satisfaction/contentment and physical function expectations among 45-54 yr olds. In Study 2, 177 adults (M age = 60.1) completed our Causal Dimension Scale for Aging (CDSA) and a survey asking whether age was a likely cause of failure in various physical activity contexts. Responses on the CDSA were used to validate ‘General Attributions towards Age’ (GATA), a measure which captured how adults view the aging effects. Subsequent analyses of variance determined that GATA interacted with physical activity status (active, less active) to influence the reported likelihood of age as a cause for failure. Less active adults with stable/uncontrollable GATA reported greater likelihood of age as a cause for failure than all other groups in gym, recreational/community program, and unstructured/spontaneous activity settings. Separate age group analyses indicated that these trends were pronounced in an unstructured/spontaneous activity setting for 45-54 yr olds, and in a generally recently inactive scenario for 55-64 yrs.

This investigation, comprising two studies, examined the number of barriers to physical activity (Study 1) and barrier strength (Study 2) reported by middle-aged and older adults using a social ecological framework (McLeroy et al., 1988). Researchers were interested in assessing age group (45-54; 55-64; 65-74 yrs) by physical activity group (active, less active) effects for barrier responses using analyses of variance. In Study 1, 180 participants completed a physical activity level survey (Godin & Shephard, 1985) and answered open-ended questions about barriers. Results indicated that 45-54 yr-olds reported more barriers overall, and more intrapersonal barriers than older groups. Less active 45-54 yr-olds reported more organizational-interpersonal barriers than the other groups. Descriptive analyses of coded themes demonstrated that common intrapersonal barrier sub-themes cited by younger adults related to family commitments, while sub-themes reported by middle-aged and older adults related to having a health problem or an injury. In the organizational-interpersonal category, the most common barrier sub-theme related to the workplace. In Study 2, 116 participants completed a survey assessing weekly physical activity and barrier strength for items pertaining to ecological categories and barrier sub-factors. Results showed that less active adults reported each of intrapersonal, interpersonal, and physical environment barriers more strongly than active adults, irrespective of age; the intrapersonal category was relatively the most constraining for our participants. In terms of barrier sub-factors, results showed that significantly higher barrier strength scores are most often associated with physical activity level (i.e., less active), and only occasionally associated with age group. The overall investigation can provide valuable information for improving physical activity interventions for middle-aged and older adults.

Neck-shoulder pain (NSP) is a highly prevalent musculoskeletal disorder with unclear causes, and effective prevention and treatment require a further understanding of the underlying mechanisms. Aberrant autonomic nervous system (ANS) regulation is a hypothesized causal element in the development and maintenance of chronic muscle pain. The overall aim of this thesis was to investigate possible differences in ANS regulation between chronic NSP and healthy control (CON) groups using both laboratory assessment and ambulatory monitoring in daily life. Four papers are included in this thesis, based on data from three groups with chronic NSP. Autonomic responses to laboratory stressors were assessed using heart rate variability (HRV), blood pressure, trapezius muscle activity and blood flow measurements (Study І) in NSP and CON. Long-term ambulatory monitoring of HRV, physical activity and perceived symptoms were assessed in Studies ІІ and IV to investigate group differences in real-life conditions. Finally, the effects of a ten-week intervention (using individually adjusted HRV biofeedback) to reinstating ANS balance in subjects with chronic NSP were evaluated using self-reported symptoms and health ratings, as well as autonomic regulation testing (i.e., evaluating HRV at rest and in response to stress) (Study ІІІ). The main findings from the four studies demonstrated aberrant ANS regulation in the NSP group compared to CON, which was predominantly characterized by diminished parasympathetic cardiac activity during rest and sleep, and altered sympathetic reactivity to laboratory stressors (Studies І, ІІ and IV). Different patterns in physical activity were observed between the NSP and CON groups, with reduced physical activity during leisure time in the NSP group (Studies ІІ and IV). Physical activity was found to be positively associated with HRV. Positive effects of HRV-biofeedback were found on perceived health, including social function, vitality and bodily pain, and improved HRV (Study ІІІ). In conclusion, imbalanced ANS regulation was demonstrated among persons with chronic NSP at both the systemic and local levels. Diminished parasympathetic activity in NSP was modulated by lower levels of physical activity in leisure time. Interventions targeting ANS functions might benefit persons with chronic NSP.

Although physical activity above a certain threshold has been associated with numerous health benefits (Warburton, Nicol, & Bredin, 2006), most Canadians are not active enough to realize these benefits (Craig, Russell, Cameron, & Bauman, 2004). In order to examine individuals own explanations of their health-related physical activity behaviour in terms of attributions, four studies testing elements of Weiners (1986) attribution theory and Banduras (1997) self-efficacy theory were conducted with a university sample. The results from the first study revealed that perceived outcome differentiated attributional explanations while objective outcome did not. Results also revealed that although predicted relationships concerning attribution-dependent emotions were largely unsupported, emotions were associated with outcomes. Further, results suggested that those making stable attributions reported more certainty of similar future outcomes than those making unstable attributions. Results in the second study suggested that attributional dimensions significantly improved the prediction of self-regulatory efficacy beyond that predicted by past success/failure to be active enough for health benefits alone. Stability appeared to be the most important attributional dimension in predicting self-efficacy. Results in the third study suggested self-regulatory efficacy significantly improved the prediction of future intention beyond that of past success/failure to be active enough for health benefits alone. The results from the fourth study supported the plausibility of self-regulatory efficacy partially mediating the relationship between stability of attributions for typical levels of exercise and intention to maintain those levels during a forthcoming final exam period for both moderate- and mild-intensity exercise. Results are discussed in the contexts of testing attribution theory and self-efficacy theory and improving understandings of physical activity behaviour.

In Canada, the prevalence of childhood overweight and obesity has increased dramatically since the 1980s. Few studies have examined factors associated with overweight and obesity in Canadian children. The purpose of this study was to: (1) explore the relationship between physical activity and BMI, (2) examine the prevalence of childhood overweight and obesity, and (3) explore the importance of age, gender, and residency (farm versus town) in relation to childhood overweight and obesity in a sample of rural Saskatchewan children.<p>This cross-sectional study included a self-report questionnaire survey and anthropometric assessment of a sample of children (Grades 4-6) from rural Saskatchewan. Of the 525 questionnaires distributed, 262 were completed with a signed consent form (response rate: 49.9%) and 251 of those students had their height, weight, and sitting height measured. The research questionnaire gathered demographic data about the child and the parents or guardian, data on the childs sedentary leisure activities, and a 7 day physical activity history using the Physical Activity Questionnaire for Older Children (PAQ-C). Each childs body mass index was estimated using the measured height and weight and these estimates were compared to international standards for BMI to estimate the prevalence of childhood overweight (25.5%) and obesity (7.1%) within the study population. There were no statistically significant gender differences in the proportion of children who were overweight or obese. The factors found to consistently have a significant association with the prevalence of overweight and obesity were Aboriginal descent and mothers and fathers BMI category. The mean PAQ-C score was similar for boys (3.3, SD = 0.64) and girls (3.2, SD = 0.57) and did not differ significantly by BMI category. <p>This descriptive study provided information on the prevalence of physical activity, overweight, and obesity in a sample of rural Saskatchewan children and the relationship between physical activity and BMI in the sample. Findings of this study can be used by nurses, other health professionals, and education leaders to develop health promotion programs to promote a healthier lifestyle for children and their families.

Background: South Asian girls have reported low levels of physical activity (PA) compared to other Canadian adolescents. Potential explanations include omissions in existing PA measures that don’t capture all types of PA, and factors discouraging PA in this group. Purpose: This study examined the quality and quantity of PA; compared PA participation using two self-report methods; and, examined psychosocial and cultural factors associated with PA in adolescent South Asian girls. Methods: 113 participants were recruited from community sources in Toronto. Data were collected using a structured electronic diary (3 weekdays; 2 weekend days) and a self-administered online questionnaire that included the Leisure Time Exercise questionnaire. Diaries were content analyzed and compared to PA reports in the questionnaire. Bivariate and multivariate regression analyses identified factors associated with PA. Results: Diaries revealed that when a range of PA types were captured, like walking activities and chores, PA levels were similar to representative data for Canadian youth. 92% of respondents reported at least 30 minutes of PA per day across their diary entries. However, 19% did not report any PA at the vigorous intensity level, and PA levels were lowest on weekends. Reports of PA in the diary and questionnaire were inconsistent, with considerably higher levels of PA reported in the questionnaire. Enrolment in physical education, enjoyment, control, fewer barriers, and social provisions were associated with greater PA. Conclusions: Physical activity levels were low, but results did not suggest that South Asian girls are more vulnerable to low levels of activity compared to other Canadian girls. Findings from the diary suggest that PA questionnaires would benefit from including a broader range of activity types with a variety of walking activities, and structured reflections to enhance data quality and minimize the potential for over-reporting. PA levels may be increased through mandatory physical education, curricula that emphasize how girls may engage in vigorous activities outside of classes, and changes to neighbourhood environments that would promote walking.

FACILITATORS AND BARRIERS OF PHYSICAL ACTIVITY IN OLDER PERSONS WHO HAVE EXPERIENCED A FALL Edwin Yoshiyuki Hanada, Master's of Science Degree, Institute of Medical Science, University of Toronto, 2008 ABSTRACT A systematic review and four focus groups were conducted to determine the facilitators and barriers of physical activity in older adults who have experienced a fall. Results from the systematic review demonstrated facilitators and barriers of purposeful and non-purposeful physical activity for older adults, but not specifically fallers. Facilitators identified in the systematic review and elaborated upon in the focus groups involving older fallers included: deriving benefits from physical activity in the physical, psychological, or functional realms; and social support providing encouragement for participation in physical activity, or acting as a distraction from negative physical symptoms during participation in group physical activity. Conversely, barriers to purposeful and non-purposeful physical activity included: symptoms of chronic illnesses, such as cardiac chest pain, arthritic pain, poor balance or poor eyesight; a fear of falling; and adverse physical environmental conditions, such as cold or warm, humid weather. The focus groups identified disinclination to activity as an important barrier to purposeful physical activity. When placed in a theoretical context such as Bandura’s Social Cognitive Theory and Marcus and Owen’s Readiness for Change model, the results of this study can help inform the design of physical activity interventions to prevent falls in older adults with a history of falls.

Introduction: Little is known about the physical activity [PA] habits of children with Autism Spectrum Disorders [ASD]. ASD specific PA barriers and facilitators have not been investigated. Purpose: To describe the PA habits of children with ASD and the barriers and facilitators to optimal PA participation. Methods: Twenty-three parents of children with ASD reported on their child’s PA habits, perceived barriers to PA participation, and functioning. A rating scale was applied to score responses and children were classified into functional level groups and PA level groups. Results: On average, children were reported to meet or exceeded national PA frequency guidelines, belonged to active families and participated in a variety of physical activities. Parents identified several barriers to optimal PA for their children. Conclusions: Children with ASD can attain optimal PA. Exposure to a variety of PA opportunities and experiences aids in identifying the ideal activity for each individual child.

Introduction: Little is known about the physical activity [PA] habits of children with Autism Spectrum Disorders [ASD]. ASD specific PA barriers and facilitators have not been investigated. Purpose: To describe the PA habits of children with ASD and the barriers and facilitators to optimal PA participation. Methods: Twenty-three parents of children with ASD reported on their child’s PA habits, perceived barriers to PA participation, and functioning. A rating scale was applied to score responses and children were classified into functional level groups and PA level groups. Results: On average, children were reported to meet or exceeded national PA frequency guidelines, belonged to active families and participated in a variety of physical activities. Parents identified several barriers to optimal PA for their children. Conclusions: Children with ASD can attain optimal PA. Exposure to a variety of PA opportunities and experiences aids in identifying the ideal activity for each individual child.