Current physical activity recommendations are being met by less than 21 % of children between 5-15 y. Recent Government initiatives are aiming to increase children’s participation in exercise. However, the effects on an imposed bout of exercise-induced energy expenditure (EE) on energy intake (EI) and appetite (hunger, fullness and prospective consumption) in normal weight children have received a limited research focus to date. Therefore, this thesis aimed to investigate how an imposed bout of exercise-induced energy expenditure (EE) on energy intake (EI) and appetite in normal weight children The first study investigated whether 17 habitually active girls were able to accurately increase their EI to match the EE following 60 min moderate intensity walking exercise. On average 17% of the EE was compensated for by an increase in EI. However, the ranged for EI change was -160% to +166% indicating large individual responses. The second study investigated whether 30 min of maximal sprint intermittent sprint cycling exercise would significantly alter EI or appetite in 13 boys and 13 girls. In the boys, hunger and prospective consumption were suppressed whilst fullness increased immediately following the exercise, whilst EI was significantly increased in response to the exercise condition. No significant changes to appetite or EI were observed in the girls. The third study investigated whether a mid-morning snack, moderate intensity cycling exercise (energy matched to snack) or both would alter EI or appetite in 20 boys and 18 girls. Irrespective of sex, hunger and prospective consumption were suppressed whilst fullness increased following the mid-morning snack, however this change in appetite did not alter EI as no significant differences were found between conditions. The fourth study investigated whether 99 recreational sports players (males/females, adults/children) were able to conceptualise their EE following 1 h habitual training into quantifiable amounts of food (chocolate) or drink (sports drink). Only 36 % of the EE from the exercise was met by the estimated amounts of food or drink. Age, sex nor sports participation significantly altered the participants’ accuracy of estimation. The fifth study investigated whether sex or dietary restraint impacted brain activation responses to visual food stimuli in 15 boys and 14 girls between a fed and fasted condition. Significant differences in brain activation were found between conditions, sexes and dietary restraint, potentially suggesting the differences observed in the previous experimental studies could be attributed to neurological alterations between participants. In conclusion, the findings presented demonstrate the changes in EI between young adolescents in response to an imposed bout of exercise are extremely variable. Whilst eating behaviours failed to correspond to the EI differences observed between participants, potentially brain activation differences may be responsible. The sex of the participant is more likely to impact EI and appetite following maximal sprint intensity exercise, more so than a bout of moderate intensity exercise. Future research should focus on determining what underpins the variable change in EI between participants following a bout of exercise.

The prevention of chronic disease requires understanding and intervention related to both individual and environmental level determinants. However, traditional approaches to chronic disease prevention and management have primarily been focused at the individual level, with limited attention toward environmental level influences on health behaviour. This lack of comprehensiveness is partially due to a paucity of complex theoretical frameworks for clarifying the influences of personal cognitive, and broader environmental, variables on a range of health behaviours. Therefore, the purpose of this research was to expand and test a popular health behaviour theory, Social Cognitive Theory (SCT), to include influences of the perceived food environment on healthy eating behaviour. This study involved two phases. Phase 1 expanded SCT to include a perceived food environment construct through review of the food environment literature. Phase 2 conducted a cross-sectional study of 201 adults (age 35 to 69 years) using an online survey to test the expanded SCT informed by phase 1. Data analysis included descriptive statistics and structural equation modeling (SEM) to compare the traditional and expanded SCT model. Results demonstrated no significant model fit, with no improvement in oveall fit with the inclusion of the perceived food environment. However, the expansion of SCT to include perceived food environment attributes altered the pathways of influence within the social cognitive model, suggesting that the presence of perceived environment measures is important for understanding how perceived environments might mediate the effect of personal cognitive influences on eating behaviour. These findings have implications for food environment research, the development of ecological theories, the field of health promotion and the prevention of chronic disease.

Despite the many benefits associated with women’s participation in sport, women athletes are often exposed to potential challenges that can negatively affect their athletic experience. The root of many challenges in sport comes from the level of performance expectations and the frequency of evaluations that women face. Self-compassion is a construct informed by positive psychology that can help people manage self-judgment, rumination, and feelings of isolation while promoting a kind and understanding perspective of the self. Further, self-compassion promotes positive self-attitude without the drawbacks associated with self-esteem; however, past research on the role of self-compassion in women athletes’ well-being is limited. This research applies a mixed methods approach to address the role of self-compassion in women athletes’ body appreciation and intuitive eating. The first phase was quantitative and expands on past research by examining how self-compassion relates to, and explains unique variance beyond self-esteem, in women athletes’ body appreciation, intuitive eating, disordered eating, compulsive exercise, and state self-criticism. Participants were 90 women athletes aged between 18 and 27 years, who participated in a variety of sports and competitive levels and completed an online survey. Self-compassion was positively related to women athletes’ body appreciation (r=.68, p< .01) and intuitive eating (r=.53, p< .01), while being negatively related to disordered eating (r=-.59, p< .01), compulsive exercise (r=-.37, p< .01), and state self-criticism (r=-.45, p< .01). Hierarchical regression analysis revealed that self-compassion contributed significant unique variance beyond self-esteem, after controlling for age and BMI (calculated from self-reported weight and height), in women athletes’ body appreciation (4.1%, p<.01), intuitive eating (8.7%, p<.01), disordered eating (9.4%, p<.001), compulsive exercise (8.3%, p<.01), and state self-criticism (7.5%, p<.01). This study supports past research suggesting that self-compassion may be a useful tool for women athletes to manage challenging or difficult experiences in sport, while adding to the literature by highlighting that self-compassion might also play a role in positive sport experiences related to body appreciation and intuitive eating. Six women athletes completed the qualitative phase. Interviews were conducted to explore how self-compassion contributes to women athletes’ experiences of body appreciation and intuitive eating. Three main themes arose from the collective case study. Self-compassion plays a role in body appreciation and intuitive eating by helping women athletes to recognize the uniqueness of sport contexts, through the promotion of awareness, and by helping them to set personalized expectations and standards. Together the quantitative and qualitative phases forward the study of women athletes’ self-compassion, body image, and eating behaviour with a particular focus on positive constructs. As such, the current study provides a foundation to explore other positive psychological constructs and constructs informed by positive psychology and to examine the impact of a self-compassion intervention on women athletes’ body appreciation and intuitive eating.

This thesis aimed to investigate the potential to increase young children s vegetable consumption by using caregivers as facilitators. This was achieved in two parts. Part I set out to investigate whether parent led interventions using three known successful methods of offering can be effective for increasing children s acceptance of a disliked vegetable. Three studies were conducted for Part I. The first tested the efficacy of these interventions, the second investigated the role of individual factors in intervention success, and the third examined the longitudinal efficacy of such interventions over two, six and 12 months. The findings suggested that parent led home-based interventions may be successful for increasing children s acceptance of disliked vegetables in the short-term, and that such interventions may be more successful for children who are more sociable and less fussy eaters. While these interventions may not be successful for sustained long-term changes, there was a lack of statistical power for these analyses and further studies with larger samples are required. Part II of the thesis sought to investigate the wider variety of methods which caregivers use to offer vegetables to their children, as well as the possible barriers to offering. These studies worked towards informing the design of future interventions as well as providing information for caregivers on achieving a healthful diet in their children. This was achieved via two studies which used qualitative and quantitative methods. One study used focus groups to gather a comprehensive report of caregivers methods of offering, as well as caregivers perceived influences on how and whether they offer their child vegetables. Methods of offering vegetables formed three main categories: active/behavioural methods, passive methods, and food manipulations. The influences on offering which caregivers perceived formed four categories: information, cost, caregiver factors, and child factors. These methods and influences were then assessed in a large scale cross-sectional study. This study examined which methods caregivers perceive as successful for encouraging consumption of vegetables, as well as assessing predictors of offering vegetables and children s vegetable consumption. Caregiver factors predicted reoffering of rejected vegetables while a combination of caregiver and child factors predicted children s consumption of vegetables. A number of discrepancies were found between methods caregivers perceived as successful and those which were associated with greater consumption of vegetables. As food fussiness was identified as a significant factor in children s consumption of vegetables, a final study investigated whether children categorised as fussy or not fussy with vegetables differed on a number of caregiver and child factors. Differences were found between these groups on both caregiver and child factors. Using a mixed methodology, the research in this thesis investigates possibilities for increasing vegetable consumption in early childhood and highlights the central role or caregivers in this process. Together, these findings suggest utility of whole family interventions aimed at increasing vegetable consumption, as well as providing caregivers with information on how best to offer vegetables to children of this age.

Introduction: Health-related behaviours of Canadian adolescents are generally suboptimal. Studies have assessed effectiveness of exercise interventions primarily from an energy balance perspective, but not from a health promotion standpoint. This study assessed the effect of an 8-week aerobic exercise program on dietary intake parameters and eating behaviours of adolescents with a normal weight and excess body weight. Methods: This quasi-experimental study involved 13 male and 13 female adolescents between the age of 14-18 years old (17 normal weight, 9 with excess weight). The intervention consisted of an 8-week aerobic exercise program on cycle ergometers, aiming for 50-75% of heart rate reserve. Diet was assessed in pre- and post-intervention via 24-hour dietary recalls. Two recalls were collected for each condition: pre- intervention, post-intervention on exercise days and post-intervention on non-exercise days. Diet was assessed for the following dietary intake parameters: food quantity, diet quality and eating patterns. Results: The 8-week exercise program led to a decrease in meal size at lunch and dinner, energy density at breakfast, carbohydrate intake as well as a slight shift in eating pattern of participants. At baseline, participants with excess weight had greater number of daily eating occurrences and portion sizes at evening snacks but consumed a smaller percentage of daily energy intake before school, compared to those with a normal weight. Participants with excess weight decreased their total number of eating occurrences, but not those with normal weight. The exercise program did not influence cognitive restraint, uncontrolled eating or emotional eating scores of participants. Conclusion: Significant changes in food quantity and eating pattern parameters, but not in diet quality, were observed following the exercise program. Differences in pre- intervention and in response to the exercise program were observed based on weight status. Future studies with greater sample size are needed to confirm these findings.

yes / Background The interaction between motivation to eat, eating behaviour traits and gut peptides following gastric bypass (GBP) surgery are not fully understood. Setting Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden. Method Appetite and hormone responses to a fixed liquid pre-load were assessed in 12 obese (BMI 45 ± 1.9 kg/m2) participants immediately before, 3 days, 2 months, and 1 year following gastric by-pass (GBP) surgery. Subjective appetite and plasma levels of ghrelin, leptin, insulin and GLP-1 were measured for a 3-hour postprandial period. Eating behaviour traits were also measured using the TFEQR18. Results There was a decrease in TFEQ Emotional Eating (EE) and Uncontrolled Eating (UE) from pre to 1-year post-surgery, but no significant change in Restraint. In addition, there was a reduction in subjective appetite ratings, and alterations in appetite peptides favouring an anorectic response. Pre-surgery EE was significantly related to fasting and AUC ghrelin; UE was associated with AUC desire to eat while there was a significant association between fasting desire to eat and ghrelin (fasting and AUC). 1 year post-surgery, UE was positively related to fasting insulin and Restraint was negatively associated with GLP-1. UE and subjective hunger were positively correlated, while the relationship between desire to eat and ghrelin remained. Conclusion The relationships amongst subjective appetite ratings, eating behaviour traits and appetite peptides in obese patients both before and at one-year post GBP surgery contribute to the reduction in a propensity to over-eat and weight loss.

No / Bariatric surgery has emerged as an increasingly popular weight loss intervention, with larger and more endurable weight loss compared to pharmacological and behavioural interventions. The degree of weight loss patients experience varies, between individuals, surgeries and over time. An explanation as to why differing weight loss trajectories exist post-surgery could be due to the complex interplay of individual differences in relation to eating behaviours and appetite. Thus the aim of this narrative review is to explore literature between 2008 and 2018, to assess the impact of impact of bariatric surgery on food selection and nutrient status, on eating behaviour traits and on disturbed and disordered eating behaviour, to determine their impact of weight loss success and weight loss trajectories. Immediately post-surgery, up until 1–2 years post-surgery, there is a reliance upon the surgery's alteration of the gastrointestinal tract to control food intake and subsequently lose weight. Energy intake is reduced, dietary adherence is higher, supplement intake is higher, appetite ratings are lower, there is a reduction in psychopathology, and an increase in wellbeing. After this point, patients become more susceptible to weight regain, as this is the point where passive observation of the weight reducing action of surgery, moves into more cognitive effort, on the part of the individual, to control energy intake. There are various factors which influence an individual's ability to successfully regulate their energy intake post-surgery, such as their level of Disinhibition, Restraint, Hunger, Emotional Eating, Uncontrolled Eating, psychopathology and wellbeing. The need for continued psychological and nutritional support post-surgery is necessary to reduce weight regain susceptibility.

Research has shown that elite female athletes competing in competitive sports may experience weight consciousness and face demands to conform to unrealistic standards of body weight. The purpose of this research was to investigate body image and dieting behaviours in adolescent female athletes and non-athletes. A self-reporting questionnaire was administered to 60 athletes aged between 13-16 years derived from eight different sporting populations, and a control group consisting of 60 non-athletes or inactive individuals aged between 13-16 years. Two major areas relating to weight and eating behaviours were examined: disordered eating and distorted body image. Other variables under investigation included current attempts at weight loss, level of acceptance of thin female stereotypes promoted by the media, reasons for dieting, and perception of one’s own body image. Results indicated that the majority of the athletes displayed a positive body image and were generally happy with their overall body shape. This group was less likely to employ weight loss behaviours. However, the non-athletes were more likely to display distorted body image and distorted eating behaviours. Consistent with the cultural expectations of thinness, large proportions of the non-athletes wished to lose weight, even though their actual weight (i.e. Body Mass Index) was normal or underweight. Weight concerns in the non-athlete group related more to attaining a media driven “ideal” of femininity. The weight concerns recorded amongst a small number of athletes were related more to improving sporting performance. Although no clinically diagnosed cases of eating disorders were recorded, eating behaviours, weight reduction practices and body image beliefs indicated that the adolescent female non-athletes may be at risk of developing disordered eating and body image problems.

Childhood overweight and obesity is a significant and increasing health problem both nationally and globally. Yet few interventions for preventing obesity have been successful, particularly in the long-term, suggesting that important factors are being overlooked. The aims of this thesis were to investigate (a) the prevalence of childhood overweight, obesity, and binge eating; and (b) the relationships between body weight, binge eating behaviour, and a set of physical, psychological, and psychosocial variables including parent body size, body dissatisfaction, size-related teasing experiences, internalisation of sociocultural messages, depression, dieting attitudes and behaviour, and emotional eating. Participants were 569 grade five and six primary school children (272 boys and 297 girls) from Catholic and Government schools across metropolitan Melbourne, Australia. Almost 25% of participants were classified as overweight or obese. Thirteen percent of participants reported engaging in overeating (with or without loss of control), 14% reported loss of control (with or without overeating), and 6% reported engaging in binge eating (overeating and loss of control). Structural equation modelling analyses found that body weight and binge eating were indirectly related. Body weight was directly and positively associated with parent body size, size-related teasing experiences, body dissatisfaction, and internalisation of sociocultural messages, negatively associated with emotional eating, and indirectly associated with depression, and dieting attitudes and behaviour. Binge eating was directly and positively related to parent body size, emotional eating, depression, and body dissatisfaction, while indirect associations were found with size-related teasing experiences, internalisation of sociocultural messages, and dieting attitudes and behaviour. A direct relationship between body dissatisfaction and loss of control was also found. Some gender differences were detected. Multivariate analysis of variance also revealed that binge eaters scored significantly higher on measures of depression, size-related teasing experiences, internalisation of sociocultural messages, and angry and worried related emotional eating than non-binge eaters. Differences were also found for participants reporting the presence or absence of overeating (regardless of loss of control) and loss of control (regardless of overeating). Overall, the study demonstrated that psychological and psychosocial factors have a significant association with both weight and binge eating behaviour in a non-clinical sample of preadolescent Australian school children. As such, future intervention programs may benefit by addressing these factors. In addition, these results support the idea of working toward the prevention of obesity and eating disorders simultaneously in children, and of extending research in this area to examine causality.

This study examined the effectiveness of a multi-dimensional education program in facilitating attitude changes in adolescent female athletes away from dysfunctional eating behaviours and restrictive body image. Although research is available for diagnosing and identifying the problems associated with dysfunctional eating behaviours and attitudes in female athletes, few preventative tools have been proposed in order to address the problem. This study involved the design, delivery and the evaluation of a proposed a multi-dimensional education model as a preventative tool. The research design involved 18 teenage female middle/long distance runners, aged between 13 and 19, who were registered with the ACT Cross Country Club. The study was a quantitative and qualitative investigation employing a pre and post test design and using the process of triangulation to increase the study's validity. It was proposed that a multi-dimensional education program might be effective in steering attitudes away from dysfunctional eating behaviours and body image and that a mixed method design may corroborate and elaborate on the findings of the study to strengthen the understanding of the potential benefits of such an education program has to its participants. Results showed that education proved to be a successful tool in facilitating attitudinal changes in a positive direction, across a number of variables such as menstrual functioning, nutrition, flexibility, strength, and general awareness, on what constitutes a balanced healthy athletic body.