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.

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.

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.

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.

Objective: To study the evidence on physical activity (PA) as an effective preventive strategy for depression. Methods: A search of electronic databases was performed for articles between 2007 and 2012, both original research and review articles, concerning the link between PA and depression on children, youth and adults. Three reviews, five longitudinal and two cross sectional studies were included. Results:  PA reduced the likelihood of depression in many studies and a sedentary or inactive lifestyle increased the risks for mental health symptoms such as depression. One study showed that low PA in childhood increased the odds of depression as an adult and other studies on teenagers saw a connection and mediation between PA and self-esteem whereas physical fitness showed no mediating effect. Many of the studies and reviews point out the insecurity regarding the dose-response association and the difficulties in defining causality. Conclusion: PA might have a preventive effect on depression. Some evidence exist to support that PA in childhood prevents depression in adults. The complex mechanism and causality need further attention and quality research is needed to determine the nature of the relationship and to verify the effectiveness of preventive programs. / Syfte: Att se huruvida belägg finns för fysisk aktivitet som effektiv förebyggande strategi mot depression. Metod: Sökning i elektroniska databaser gjordes efter både studier och litteraturgranskningar publicerade mellan 2007 och 2012 med avseende på kopplingen mellan fysisk aktivitet och depression hos barn, ungdomar och vuxna. Tre litteraturgranskningar, fem longitudinella och två tvärsnittsstudier inkluderades. Resultat: Fysisk aktivitet reducerade sannolikheten för att utveckla depression i många av de populationer som studerades och stillasittande eller inaktivt liv ökade risken för mental ohälsa såsom depression. En studie visade att låg fysisk aktivitet i barndomen ökade oddsen för depression som vuxen och andra studier såg en koppling och medlande funktion hos fysisk aktivitet och självkänsla hos tonåringar emedan fysisk kondition inte såg ha någon medlande effekt. Emellertid pekar många av författarna på en osäkerhet gällande dos-responssamband samt svårigheter i att bestämma kausalitet. Slutsatser: Fysisk aktivitet kan ha preventiv effekt mot depression. Viss evidens finns för att den i barndomen kan verka förebyggande mot depression i vuxen ålder. De komplexa sambanden och kausaliteten bör utforskas vidare och studier av hög kvalitet behövs för att bestämma orsaker och samband samt preventiva insatsers effektivitet.

Depression är en sjukdom där forskarna inte är överens om dess uppkomst. Forskning tyder på att depression år 2020 kommer att vara den näst vanligaste sjukdomen i världen. Fysisk aktivitet är viktigt för folkhälsan och påverkar individen såväl fysiskt som psykiskt. Syftet med denna litteraturstudie var att belysa sambandet mellan depression och fysisk aktivitet. Resultatet baseras på 14 artiklar som relaterar till syftet. Resultatet visade att de personer som är fysiskt aktiva har minskad risk att uppleva psykiska besvär som depression. Det finns även ett samband mellan hur mycket fysisk aktivitet som utförs och graden av depression. Sjuksköterskan har en viktig roll både vad det gäller förebyggande och lindrande av depression. Genom dialog med patienten kan fysisk aktivitet föreslås som ett komplement till den medicinska behandlingen. Det kan räcka med ett par promenader i veckan för att risken för uppkomst av depression samt depressionssymtomen hos dem som lider av depression skall minska. Om fler människor motionerar regelbundet skulle med största sannolikhet depressionsfrekvensen minska. Vidare forskning inom området samt implementering av den kunskap som finns bör göras. Det är viktigt att den positiva effekten av fysisk aktivitet vid depression når fram till alla professioner inom hälso- och sjukvården och att den implementeras i verksamheterna. Detta kan på sikt tillsammans med ytterligare forskning leda till att viss del av den medicinska behandlingen kan ersättas med fysisk aktivitet. / Depression is a disease where scientists are not in agreement on its origin. Research indicates that depression will be the second most common disease in the world year 2020. Physical activity is important for the public health and benefits the individuals both physically and psychologically. The purpose of this literature study was to illustrate the relation between depression and physical activity. The result is based on 14 articles which relate to the purpose. The result showed that persons who are physically active have less risk of suffering from psychological difficulties such as depression. There is also a connection between how much physical activity that is carried out and the degree of depression. The nurse's role is important to prevent and relieve depression. In consultation with the patient, physical activity can be suggested as a complement to medical treatment. It can be enough with a couple of walks per week to prevent beginning of depression as well as ease symptoms for those who already suffer from depression. If more people exercised on a regular basis the frequency of depression would most likely be reduced. Further research in this area should be carried out as well as the implementation of knowledge that already exists. It is important that the beneficial effects, which physical activity has on depression, reach all relevant persons within health and medical care industries and that it is implemented. In conjunction with additional research this can lead to physical activities being partial replacement to medical treatment.

Meaningful teaching in physical education – A study of pupils opinions of the contents and teachers methods to activate and account inactive pupils. Nowadays people in society are getting more and more inactive, and we have during our practice at different schools, noticed that many pupils are uncalled for and inactive at the lessons in physical education. The purpose with the study is to see what pupils in the ninth grade thinks about the contents of the subject and what they want it to contain to make the teaching more meaningful. The study also looks in to different methods that teachers in physical education use to make the lesson feel meaningful for all the pupils and how they work to activate and account inactive pupils. To collect the information we chose to distribute questioners to pupils and do interviews with teachers. In question of contents, the pupils want to do activities with a high level of effort and they want to have a varying and challenging teaching. To create a context the pupils wanted more theory and they think that the teaching gets more meaning if they get more responsibility and have influence over the lesson. To activate and account the inactive pupils, the teachers in this study tries to create a secure environment and they think it’s important with an open dialogue whit their pupils. They want to make their pupils feel competent and secure enough to participate in the teaching. Different methods they used were to find special solutions and adapt the teaching after individuals and levels to activate all the pupils.

Durch eine geringe Geburtenrate und eine steigende Lebenserwartung steigt die Zahl an alten Menschen in unserer Gesellschaft drastisch an. Es kommt zu bedeutenden demographischen Veränderungen. Die Vielzahl älterer Menschen führt zu einem bewussten Wahrnehmen des Alterns. So hat sich die Sichtweise auf das Altern verändert und die negativen Ansichten werden zunehmend durch die Erkenntnis der Vielfalt des Alters ersetzt. Dabei ist Altern nicht nur ein biologischer Prozess, sondern ein multidirektionaler und multidimensionaler Prozess, der durch eine Vielzahl von endogenen und exogenen Faktoren beeinflusst wird. Ein wichtiger Einfluss¬faktor ist die körperliche Aktivität. Viele Studien zeigen, dass körperliche Aktivität altersbedingte Abbauprozesse aufhalten und die psychische Gesundheit sowie die kognitive und körperliche Leistungsfähigkeit fördern kann. Neben physischen und psychischen Ein¬schränkungen kommt es mit zunehmendem Alter zu Leistungsverlusten in den kognitiven Funktionen und der körperlichen Leistungs¬fähigkeit. Der Forschungs¬stand zeigt, dass durch körperliche Aktivität die körperliche Leistungsfähigkeit trainierbar ist und die psychische Gesundheit verbessert sowie die kognitiven Funktionen gefördert werden können. Allerdings ist derzeit nicht klar, welche Form der körperlichen Aktivität die größten Verbesserungen in der psychischen Gesundheit und den kognitiven Funktionen für die Ziel¬gruppe der über 60Jährigen erzielt. In der vorliegenden Arbeit wurde das Thema der körper¬lichen Aktivität im Alter aufgegriffen. Ziel der Arbeit ist es, den Alternsprozess durch körperliche Aktivität positiv zu beeinflussen und die psychische Gesundheit sowie kognitive und körperliche Leistungs¬fähigkeit zu verbessern. In dieser randomisierten, kontrollierten Studie werden ein 12-wöchiges Kraft¬training und kombiniertes Kraft- und Ausdauertraining auf ihre Effektivität in den Bereichen psychische Gesundheit, mit den Indikatoren Depressivität und Angst, den kognitiven Funktionen mit den Variablen Kurz- und Arbeitsgedächtnis, Wortflüssigkeit, Informationsverarbeitungsgeschwindigkeit, exekutive Funk¬tionen und körperliche Leistungsfähigkeit mit den Komponenten Kraft und Ausdauer untersucht. Die Zielgruppe bilden gesunde, inaktive Senioren über 60 Jahre.

The purpose of this study was to investigate the extent to which acculturative stress is associated with physical activity levels of international students, the influence of types and sources of social support on their physical activity levels, and the degree to which social support affects the relationship between their physical activity levels and acculturative stress. 215 Korean international students from Bryan-College Station, Texas, were recruited for this study. The results revealed that only the stressor of English language difficulty, one of acculturative stress, negatively influenced physical activity levels. Social support was positively associated with physical activity levels. Finally, in the role of social support between acculturative stress and physical activity levels, the support of Korean friends and American friends positively affected vigorous physical activity level. These results suggest that social support for international students is likely to be one of most important factors for their physical activity levels. Since the convenient sample of Korean international students may not be representative of international students in the United States, further study needs representative samples in order to establish the generality of international students studying in the United States. Moreover, future research is necessary to examine various sources and types of social support which influence physical activity of international students.