<p>Various factors, including low levels of physical activity (PA), and high consumption levels of sugar-sweetened drinks (SD), have been implicated in the general increase of fat mass (FM) levels seen in youth. <b>Purpose</b>: To determine if a significant relationship exists between fat mass (FM) and physical activity (PA) or sugar-sweetened drink (SD), in boys and girls, using longitudinal analysis. <b>Methods</b>: 105 boys and 103 girls were assessed repeatedly during childhood and adolescence, for a maximum of 7 years. Height was measured annually, as was fat free mass (FFM) and FM estimated by dual X-ray absorptiometry (DXA). PA was evaluated bi-annually using a questionnaire for children (PAQ-C/A: 1 low, 5 high), and SD was assessed using a 24-hour dietary intake questionnaire completed 1-4 times/year. Years from peak height velocity were used as a biological age indicator. Random effects models were used to analyze the data, subsequent to log linearization of the FM variable since it was not initially normally distributed. <b>Results</b>: The constructed model, controlling for maturation, FFM, and adjusted energy intake, found no interaction effect between SD and PA (p>0.05). After removal of the interaction term from the model, SD was found to have no significant relationship (p>0.05) with FM of boys or girls. In contrast, PA level was found to have a significant relationship (p<0.05) with FM of males; but not with FM of females. <b>Conclusion</b>: The longitudinal models employed revealed a significant negative relationship between level of PA and FM in males but not females, after controlling for maturational status, body size and dietary energy intake. This finding lends support, to proponents of increasing PA in youth to control FM. Regarding SD and FM, the models employed showed no relationship. Future investigation with more complex models, accounting for more covariates, may be warranted in this area.</p>

Active transportation (AT) is a form of physical activity involving human-powered transportation (e.g., walking) and is associated with health benefits. However, the majority of Canadians do not use AT. Although environmental factors, such as proximity, are correlated with AT, interventions to change such factors have been ineffective. According to social cognitive theory, both environmental and personal factors (i.e., social and spatial cognitions) may influence motivated behaviour. The social cognitions of interest in the present study included self-regulatory efficacy to schedule (i.e., confidence to regularly schedule walking for AT), and to overcome barriers (i.e., confidence to cope with barriers to walking for AT). Spatial cognitions included distance and travel time cognitions. The purpose of the study was to examine whether social cognitive personal factors (i.e., scheduling self-efficacy, barriers self-efficacy), spatial cognitive personal factors (i.e., distance and travel time cognitions), and an environmental factor (i.e., proximity) were associated with walking for AT to/from a university campus over a two-week period in a convenience sample of adults. Participants in this prospective observational study were a convenience sample of 105 students, faculty, and staff at a western Canadian university, who ranged in age from 17 to 55 years (M = 24.62 years, SD = 8.15). Participants completed three online surveys over a two-week period. Social cognitions for the following two-week period and spatial cognitions were assessed at Time 1. Recall of walking for AT to/from a university campus in the previous week was assessed at Time 2 and Time 3. Total walking for AT to/from campus over the two-week period was the outcome variable. The overall hierarchical multiple regression model predicting AT from the social and spatial cognitions and proximity was significant (R2adjusted = .53; p < .01). As hypothesized, scheduling (ßstd = .44, p < .01) and barriers (ßstd = .23, p < .05) self-efficacy were associated with AT. Scheduling self-efficacy was the strongest predictor. Contrary to hypotheses, distance and travel time cognitions and proximity were not significant (ps > .05). Social cognitions, particularly self-regulatory efficacy to schedule, and efficacy to overcome barriers, may play an important role in individuals use of walking for AT to/from a university campus. Future research should continue to examine social cognitive-theory based personal and environmental predictors of AT, such as self-regulatory efficacy to goal set, outcome expectations, the weather and residential density, to better understand potential determinants of this health-promoting type of physical activity.

While it has been long known that the behaviour of others can influence individual behaviour, norms (the views and behaviours of others) are not generally reported as strong motivators of physical activity. Using the theory of normative social behaviour as a guiding framework, the purpose of this research was to examine if descriptive norms (the perceived prevalence of others behaviour) would be more important in predicting activity than previously suspected. A secondary purpose was to extend this examination to another health behaviour, healthy eating. Three independent studies were conducted. The first two studies examined what individuals thought motivated their physical activity (Study 1) and eating (Study 2) as well as the relationship between descriptive norms and participants own activity behaviour and healthy eating intentions. Results revealed that, despite being rated by participants as less motivating, descriptive norms were stronger predictors of activity behaviour and healthy eating intentions than other well-established non-normative reasons. It also was found that descriptive norm perceptions about a group proposed to be high in group identity (i.e., friends) was most related to physical activity behaviour and healthy eating intentions. To extend these results, a third study manipulated normative and non-normative messages to examine effects on physical activity. Participants were grouped into one of four conditions (descriptive norm, health, appearance, and control) and received motivation-based email messages specific to their condition encouraging them to be active. It was hypothesized that participants in the descriptive norm condition would experience the greatest increase in physical activity but results did not support this hypothesis, as participants across all conditions significantly increased total physical activity after receiving the messages. A secondary hypothesis examining the focal nature of the targeted behaviours was supported in that responses to normative messages were greatest with the most focal behaviour (using the stairs). Taken together, the results of the first two studies provide preliminary evidence to suggest that the relationships between both descriptive norms and physical activity and descriptive norms and healthy eating may be going undetected. In light of the results of the third study, however, future studies are needed.

Recently, the Saskatoon in motion physical activity health promotion initiative has worked with educators and high school administrators in the city of Saskatoon to develop a targeted physical activity strategy for high school students. The in motion high school strategy was implemented in each school by an in motion high school champion. In each school in motion could incorporate such things as announcements, bulletin boards, posters, physical activity clubs and physical activity challenges. The strategy was piloted in a Saskatoon high school previously and had positive impact on students activity levels. Purpose: To investigate the effectiveness of the in motion strategy at impacting the physical activity behaviour of a large sample of Saskatoon high school students, and to uncover how in motion could be better supported in the school environment. Method: in motion was implemented in eight Saskatoon high schools from October to June of the 2005/06 school year. Study participants were male and female students, from grades 9-12, attending the eight schools. The Godin Leisure Time Exercise Questionnaire was administered in October 2005 (n = 4395), and May 2006 (n = 3299) to assess self reported physical activity, and analysed using independent t-tests and ANOVA with Tukey post hoc tests.<p>In June of 2006, questionnaires were administered to the in motion champions (n = 8). Questionnaires inquired into the specific activities and events that comprised the in motion intervention in each school and champion experiences with in motion. Information obtained led to the classification of dose of intervention implemented at each school. Schools were separated into high, moderate, and low dose categories, and a dose-response relationship between dose of intervention and change in physical activity level was investigated. Qualitative data was analysed using typological analysis, and represented as summary of responses. Results: An overall increase in self-reported physical activity was found after the implementation of the in motion physical activity intervention (t (3920.355) = -21.15, p < 0.0001). Increases were observed in all genders, grades, and schools. Two schools were deemed high dose, four moderate dose, and two low dose. No dose-response relationship was found between dose of in motion and change in physical activity or students opinion of how in motion impacted personal activity levels. Dose-response relationship was found between dose of intervention and recognition of in motion. Additionally, through champion questionnaires, multiple supports and barriers for the in motion intervention, and suggestions for how in motion could be improved, was given by in motion champions. Conclusions: Student opinion of in motions impact on their personal activity level indicates that in motion is a promising tool for increasing physical activity in students. Lack of dose-response relationship between intervention and physical activity change, and student opinion of how in motion has affected activity level suggests that the definition of dose is too narrow. To further support in motion in schools, more staff involvement and appropriate activities for different demographic groups are needed.

Urban Aboriginal youth are one of the fastest growing populations in Canada (Statistics Canada, 2008). There is growing concern with the increasing rate of overweight and obesity among Aboriginal youth (Reading, 2009). Although this unique group is quickly growing, and possibly experiencing more ill health than non-Aboriginal youth their voices are currently absent in Aboriginal health literature. Drawing on the voices of urban Aboriginal youth to understand their perspectives is important for the promotion and enhancement of overall health (RCAP, 1996). One specific topic absent from the literature is the influence of culture on body weight, physical activity, and diet for urban Aboriginal youth. (Gittelsohn et al., 1996; Kumanyika, 1993; Marchessault, 1999; Thompson, Gifford, & Thorpe, 2000; Willows, 2005). Culture is seen as the beliefs, behaviours, norms, attitudes, and social arrangements that form patterns in the lives of members (LeCompte & Shensul, 1999, pg 21). The purpose of this study was to examine the influence of culture on body weight, physical activity, and diet for urban Aboriginal youth.<p> This study used the qualitative methodology of focused ethnography. The study setting was an urban Aboriginal high school in Saskatoon, Saskatchewan, Canada. Fifteen participants (11 females, 4 males) took part in this study. Participants were between the ages of 14-21, with a mean age of 16.73. Methods of data collection included semi-structured interviews, informal conversations, talking circles, and participant observation. The researcher spent 10-15 hours a week for eight months on site in the research setting.<p> In this study four themes describe the influence of culture on body weight, diet, and physical activity. These themes were: (i) acceptance of our bodies, (ii) playing together, past and present, (iii) traditions and sharing, and (iv) the struggle. The young urban Aboriginal participants in this study believed that a healthy body weight comes in a variety of sizes. There was a general acceptance in the diversity of healthy body weights and sizes. Group physical activity and competitive activity was favoured among participants. Traditional physical activities such as dancing, hunting, and fishing were cited as important by all participants. Participants believed traditional foods to be healthy and desirable, and those who reported eating traditional foods less frequently desired to eat them more often. Food sharing networks consisting of friends and family were reported as a way to address food insecurity and acquire traditional foods from the participants home reserves. In this study barriers to physical activity and diet for urban Aboriginal youth were income, location or residence, and transportation. Participants attempted to overcome them when it was possible, which highlights a resiliency among urban Aboriginal youth.<p> In conclusion, this study offers valuable information on the influence of culture on body weight, physical activity, and diet for urban Aboriginal youth. Participants in this study engaged in a variety of traditional and cultural activities. These activities increased the healthy eating habits and physical activity levels of the participants. Thus, cultural engagement may be a health enhancing mechanism for urban Aboriginal youth in Canada.

Physical activity and healthy eating are key components of healthy living, and they reduce the risk of developing chronic diseases. Current research indicates that Canadian early years children are not active enough for healthy growth and development. Additionally their diets are high in processed foods and lack fresh and locally grown foods. Parents play a key role in establishing healthy behaviours; however caregivers also have a strong influence, as many early years children spend a large portion on their day in care centres. To date, very little is known about the factors influencing rural caregivers in the provision of healthy opportunities for early years children in their care. Purpose: The purpose of this study was to use an ecological framework to identify facilitators and barriers that rural caregivers face when providing physical activity and healthy eating opportunities in care centres. Methods: Caregivers (N = 8) in rural settings participated in one on one semi-structured interviews. Perceived facilitators and barriers reported by caregivers were categorized using the ecological model as (intrapersonal, interpersonal, institutional, community, and policy). Results: Caregivers identified facilitators and barriers. (i.e., personal health and wellness, caregiver perceptions of lack of parental knowledge, parental support and access to facilities and local foods in the community), that influenced their ability to provide physical activity and healthy eating opportunities for children in their care. Similar barriers and facilitators were clustered together to create themes within each ecological category. A total of 12 key themes emerged from the data. Conclusion: Rural caregivers identified a number of factors that facilitated and inhibited their ability to provide opportunities for engaging in health promoting behaviours. Interestingly caregivers did not identify any intrapersonal barriers. Factors in the interpersonal category were the most commonly reported. Thus behaviours of others were the often indicated as a key factor influencing caregivers in the provision of healthy opportunities. In the institutional and community categories caregivers identified a number of facilitators that supported them in the provision of healthy opportunities. Additionally, some caregivers discussed practices they used to overcome barriers and this in turn, facilitated the promotion of physical activity and healthy eating within the care centres. Research in rural areas is limited and the majority of studies focus the barriers to living in rural areas. This study contributes to the literature because it identified, not only challenges, but also benefits to living in rural areas. Furthermore, the use of an ecological framework allowed barriers and facilitators to be classified into distinct categories. This is important, as classification of specific factors can aid in designing initiatives that target facilitators and alleviate barriers. Such initiatives can then support early years caregivers in the provision of healthy opportunities for children. In turn, this will aid Canadian early years children in establishing lifelong physical activity eating and healthy eating patterns.

The metabolic syndrome has become a major public health challenge world-wide and, at least in the industrialized world, the prevalence of the metabolic syndrome is increasing. There is evidence to show that biological and lifestyle risk factors for metabolic syndrome are present in adolescence, which suggests that the antecedents of the disease may lie in early life. The period of adolescence is characterized by a decline in physical activity (PA; lack of PA is a lifestyle risk factor for metabolic syndrome) and an increase in fat mass deposition (a biological risk factor for metabolic syndrome). Therefore, investigating how the development of these two variables relates to adult cardiometabolic risk is important to fuel early intervention. A factor which has the potential to influence these two risk factors, and thus ultimately the metabolic syndrome, is the timing of biological maturity (i.e. whether an individual is early, average or late maturing when compared to peers of the same age). The influence of biological maturity has largely been overlooked in previous research; therefore, the general objective of this thesis was to investigate the associations between biological maturity, adolescent PA and fat mass development, and young adult cardiometabolic risk. Three studies were necessary to realize this objective, and together help to elucidate the role of biological maturity in the adolescent decline in physical activity, fat development, and the development of adult metabolic syndrome. Ultimately, this information will aid in the development and implementation of interventions to decrease prevalence of metabolic syndrome.<p> Study 1: The purpose of study 1 was to investigate whether observed gender differences in objectively measured PA in children (8 to 13 years) are confounded by biological maturity differences. Methods: Four hundred and one children (194 boys and 207 girls) volunteered for this study. An Actigraph accelerometer was used to obtain 7 consecutive days of minute-by-minute PA data on each participant. Minutes of moderate to vigorous PA per day (MVPA), continuous minutes of MVPA per day (CMVPA), and minutes of vigorous PA per day (VPA) were derived from the accelerometer data. Age at peak height velocity (APHV), an indicator of somatic maturity, was predicted and individuals aligned by this biological age (years from APHV). Gender differences in the PA variables were analyzed using a two-way (gender X age) ANOVA. Results: Levels of PA decreased with increasing chronological ages in both genders (p<0.05). When aligned on chronological age, boys had a higher MVPA at 10 through 13 years, a higher CMVPA at 9 through 12 years, and a higher VPA at 9 though 13 years (p<0.05). When aligned on biological age, PA declined with increasing maturity (p<0.05); however gender differences between biological age groups disappeared. Conclusion: The observed age-related decline in adolescent boys and girls PA is antithetical to public health goals and as such is an important area of research. In order to fully understand gender disparities in PA, consideration must be given to the confounding effects of biological maturity.<p> Study 2: Understanding the influence of biological age (BA) on the decline in PA would better inform researchers about the effective timing of intervention. The purpose of study 2 was to describe the PA levels and perceived barriers to PA of adolescent girls grouped by school grade and biological maturity status (i.e., early or late maturing) within grades. Methods: 221 girls (aged 8-16 years; grades 4-10) wore an Actical accelerometer for 7 days and then completed a semi-structured, open ended questionnaire on perceived barriers to PA over the 7 day period. Predicted APHV and recalled age at menarche were used to assess maturity among the elementary and high school girls, respectively. Maturity and grade group differences in PA were assessed using MANCOVA and independent sample t-test, and barriers to PA using chi squared statistics. Results: Daily minutes spent in MVPA decreased by 40% between grades 4 to 10. Within grade groupings, no differences in PA were found between early and late maturing girls (p>0.05). Grades 4-6 participants cited more interpersonal (i.e., social) barriers. Grades 9-10 participants cited more institutional barriers to PA, primarily revolving around the institution of school. No differences were found in types of barriers reported between early and late maturing girls. Conclusion: Since PA and types of perceived barriers to PA were dependent on grade, future research should work to identify the most salient (i.e., frequent and limiting) barriers to PA by chronological age in youth.<p> Study 3: Although the metabolic syndrome is thought to be mainly a consequence of obesity, the mechanisms underpinning its development are not that well understood. The purpose of study 3 was to examine total body fat mass (FM), trunk FM and PA developmental trajectories (aligned to BA; years from APHV) of individuals categorized as low and high for cardiometabolic risk at 26 years, while investigating biological and lifestyle risk factors. Methods: The sample were 55 males and 76 females from the Saskatchewan Pediatric Bone Mineral Accrual Study (1991-2007) who were assessed from childhood to young adulthood and had a measure of cardiometabolic risk at young adulthood (26.0 + 2.3 yrs). Height was measured biannually. Total body FM and trunk FM was assessed annually by dual energy-X-ray absorptiometry. PA and dietary intake was evaluated two to three times annually using surveys. Individuals were grouped into maturity status groups (early, average or late) depending on their APHV. Two composite cardiometabolic risk scores were calculated for males and females separately. The first was derived for a sub-sample (N=48) by summing the standardized residuals of inverted high-density lipoprotein cholesterol, homeostasis model assessment for insulin resistance, mean arterial pressure (MAP) and fasting triglyceride levels. A second score was derived for the whole sample by summing the standardized residuals for MAP. Scores for both samples were regressed on to age and adult smoking status. High and low cardiometabolic risk groups were determined based on a sex- specific median split of risk scores. Data were analyzed using random effects models. Models were built in a stepwise procedure with predictor variables added one at a time, using the log likelihood ratio statistic to determine if one model was a significant improvement over the previous one. Results: The final model indicated that once the independent effects of maturity (years from APHV) and height were controlled, the high risk group males and females had significantly (p<0.05) greater total body FM and trunk FM development at all ages. No association was found between young adult cardiometabolic risk and development of PA. Furthermore, in general, timing of biological maturity was not associated with development of PA or FM. Conclusion: Young adults at higher cardiometabolic risk have greater body fat as early as 8 years of age, which lends support to early intervention.<p> General Conclusions: Adolescence has been highlighted as a critical period for the development of adult disease, such as the metabolic syndrome. Results from this thesis support this contention by showing a decrease in PA (by both chronological and biological age) in males and females across adolescence. It further showed that an increase in total and central fatness during adolescence may be critical for the development of the metabolic syndrome in adulthood. Timing of biological maturity, in general, was not shown to have an independent impact on adolescent or young adult PA, adolescent perceived barriers to PA, fat mass development, or young adult cardiometabolic risk. However, further research is required before definitive conclusions can be made about the short and long term impacts of timing of biological maturity on health.

Increased prevalence rates of overweight and obesity (OW/OB) have been reported among Aboriginal women and while the literature suggests that changes in lifestyle (i.e. physical activity and diet) account for this trend, few studies have explored how the physical and sociocultural environments and individual attitudes and beliefs regarding physical activity (PA) and healthy eating may contribute to the increase. The purposes of this project were to: 1) Determine the current prevalence of OW/OB in the community, 2) assess changes in OW/OB from 1991 to 2005, 3) assess current PA and dietary practices, and 4) explore the influence of the physical and sociocultural environments as well as individual attitudes and beliefs regarding PA and healthy eating among the females in the community.<p> The prevalence of OW/OB was 26% among youth and 68% among adults. Overall, no significant difference in rates of OW/OB among youth or adults occurred over time, however there was a significant decrease in rates of OW/OB for adult males and a tendency towards a greater increase in OW/OB among female youth. A pattern of abdominal obesity among all age groups of females was noted. There was a significant increase in body mass index (BMI) classification over time among individuals with serial data. Walking and housework were the most frequently reported activities. Although the PA data suggests levels associated with health benefits, these results must be interpreted cautiously given housework was performed at a low intensity. Personal, community-specific and environmental factors were highlighted as barriers to PA, whereas organized, age-specific, women-only programs were highlighted as potential enablers for PA. Low intakes of fruits and vegetables and milk products across all age groups, with high intakes of foods high in fat, oil, sugar, salt, particularly among those under 25 years were reported. Traditional food use increased with increasing age, however was low even among women aged 55+. While food preference was influenced primarily by taste, barriers to healthy eating were largely related to geographic location. Collectively, the results of this study emphasize the importance developing community-based health promotion programs that focus on reducing identified barriers to PA and healthy eating to promote healthy body weights in the community.

Test anxiety can act as a major inhibitor for students to perform to their ability. Students can find that what life decisions they are going to be afforded is going to be determined by a series of multiple choice mathematics questions. There must be a way to deal with their test anxiety so that the true nature of their knowledge is displayed, and in the process promote learning. Meditative breathing, stretching, and physical activity have been shown to reduce stress. Furthermore, physical activity has also shown an effect on behavioral and cognitive states. This study investigates if these activities can be used in the classroom to promote learning and achievement within a mathematics course. In order to find students who share a minimum level of physical fitness and operate under some of the most stressful conditions possible, the participants were chosen from mathematics courses taught to sailors while on deployment. Two same class ships were chosen to be a part of the study. Each ship had courses split into exercise groups and a control group. Students were given a pre-test followed by eight weeks of instruction and then a post-test, interview data was collected after the course. During the instruction, weekly reviews were set so control groups were rewarded with points for correct answers and exercise groups were tasked with physical activity for incorrect answers. Study A found that post test scores were not significantly different between the exercise and control group. However, the exercise group did attend more tutoring events than their counterparts. Interview data did indicate students in the exercise group felt a greater sense of engagement, fun, and camaraderie. Based upon variations in mathematic exposure between the two groups another study was planned to find participant groups that were closer reflections of each other. Study B was conducted with a more reflective representation of student math background. The results found that the exercise group scored higher in post-test and tutoring events than the control group. Interview data also showed consistent results with Study A, where the exercise group reported a greater sense of engagement, fun and camaraderie.

Although physical activity has been identified as important for children and adolescents health, a majority are not active enough to receive health benefits. Given that physical activity lapses have been identified in adolescents, and social influences have been related to physical activity, the overall purpose of this dissertation was to explore the social influences that occur following a lapse by using a social control framework. Three studies were conducted to examine whether physical activity lapses would be associated with parental use of social control (Study 1 and 2) as well as whether this use of different social control types would be associated with changes in behaviour (Study 2 and 3) and affect (Study 3). Results from Study 1 revealed that parents reported the use of three types of social control (i.e., positive, collaborative, and negative) following a hypothetical physical activity lapse. Results from Study 2 revealed that adolescents who experienced a lapse reported greater increases in the use of positive and collaborative social control if they had an active family. Changes in social control also were associated adolescents recovery from a lapse, with collaborative social control emerging as the strongest social control type. Results from the third study revealed that each of the three types of social control were associated with behaviour change, but in a different way. Behaviour change was associated with the use of collaborative social control, the need for congruence between preferences and use for positive social control, and the perceptions of negative social control as supportive. Perceived supportiveness for all tactics was related to affect. These results provide preliminary support for the suggestion that social control may be one framework to help explain the use of parental social influences following a lapse. Future directions and complementary theories are discussed.