Background: The compulsion to test one's endurance capacity is widespread in modern society, demonstrated for example by the increased participation rates within adventure sports (Jirasek, 2007). Psychologically based evidence within the corpus reveals that effective coping mechanisms, conducive to elite ultra-endurance athletes performance, is limited. Objectives: The aims of the thesis were four-fold. Firstly, clarification of the stressors elite endurance athletes encounter during their sporting disciplines was sought. Secondly, the study aimed to establish specific, effective coping mechanisms which these athletes implement to overcome stressors. A coping framework was then developed from the information gleaned from the gathered data. Finally, the effectiveness of specific coping mechanisms were illuminated, and the coping framework was tested for accuracy. The overall aim of the thesis is to provide performers and sports psychologists with a comprehensive framework for managing and guiding ultra-endurance based athletes. Method: A mixed methods approach was implemented. A qualitative research approach, guided by grounded theory was employed to contextualize the complexities of elite ultra-endurance athletes coping methods. Semi-structured interviews were conducted with an international cohort of elite, information rich specialists, specifically mountaineers (N=lO) and ultra-distance runners (N=8). Participants also completed the Athletic Skills and Coping Inventory for Sport questionnaire (ASCI-28; Smith et al., 1995). In addition, a case study was adopted to investigate the effectiveness of specific coping tools and test the accuracy of the coping model. Findings: Stressors emerged from personal (e.g., fear), organisational (e.g., social support) and competitive (e.g., opponents) sources, supporting past literature (e.g., Fletcher & Sarkar, 2012). Coping emerged from emotion (e.g., self-talk), approach (e.g., imagery), problem (e.g., goal setting) and appraisal (e.g., self-deception) based approaches. Stressors were linked to specific, effective coping mechanisms, and the benefits of contemporary coping mechanisms, such as mindfulness and meditation, were illuminated. The value of the coping framework for endurance athletes was verified. Recommendations for future research include further exploration into mindfulness as an effective coping mechanism for endurance athletes

Aim: To assess the effect of high-intensity interval training on clinical and physiological outcomes in adults with inclusion body myositis and mitochondrial disorders, and sedentary adults with no myopathy. Methods: Subjects completed high-intensity interval training three times per week for 16 weeks on a bicycle ergometer. Training involved short bursts of cycling at a rate of perceived exertion of 16-18/20 on the Borg Scale, interspersed with active recovery intervals. Clinical and physiological outcomes included (i) peak work and aerobic exercise capacity (ii) resting heart rate variability (iii) lower limb strength performance (iv) whole body composition (v) fasted blood profiles (vi) fatigue impact and symptoms of anxiety and depression (vii) overall mental well-being and health-related quality of life. Results: Subjects with inclusion body myositis and mitochondrial disorders completed ≥ 70% of perceptually regulated high-intensity interval training, showing improvement in mental well-being and peak work capacity. Results also demonstrated the importance of modifiable co-morbidities, such as weight, that may contribute to individual exercise responses and general health status. Conclusion: Adults with inclusion body myositis and mitochondrial disease were able to safely perform high-intensity interval training with access to clinical support. Improvement in psychological and physiological outcome measures suggests that high-intensity interval training has therapeutic potential as an alternative to moderate-intensity continuous aerobic exercise.

There is a widespread belief among elite level athletes and their coaches that adequate sleep is pre-requisite for those seeking to achieve optimum performance. Despite the prevalence of this belief, combined with the common occurance of sleep complaints among athletes, there has been surprisingly little empirical investigation of sleep in this population; the vast majority of sleep research takes place in normal populations, and employs methods of sleep disturbance that are not relevant to elite level athletes. When athletes have been studied, investigations thus far have failed to measure sleep objectively during the competitive season, and have relied on subjective and retrospective self-report. The aim of this thesis has been to examine the prevalence of sleep disturbance among elite level athletes, and to investigate the impact that sleep can have on subsequent performance both in training for competition and in competition itself. The impact that training and competing in elite level sport could have on sleep was also investigated, as were a number of other factors related to elite level competition. A total of 68 elite level athletes, both male and female, from 3 different sports (football, basketball, swimming), volunteered to have their sleep measured by wrist actigraphy for a period of at least 2 weeks. Twenty-seven age-matched sedentary participants were similarly recruited to act as a control group. Thirty-three professional football players, playing in either an England and Wales Premiership or Championship football club continued to have their sleep measured by wrist actigraphy for a period of eight weeks of the regular competitive season, during which their on-pitch performance was measured by means of the ProZone® player tracking system, and their performance in training was measured by the Catapult X3® GPS system. Both measures are widely used currently to measure performance in professional football, ensuring that performance was measured as it occurred naturally instead of in a contrived setting. Wrist actigraphy was similarly chosen since it allows for long term objective measurement of sleep. In agreement with anecdotal reports and previous research, evidence of a significant level of sleep disturbance was found among all the types of elite athletes studied. A number of stressors associated with elite competition also demonstrated a significant impact on sleep, particularly to sleep timing following matches, and more generally as a consequence of physical activity during evening matches. Sleep did not have a statistically significant impact on subsequent performance during matches, although, given the narrow margins between success and failure involved in competing at such a high level, the size of the effect in evidence may still have important implications for athletes and coaches. Sleep also demonstrated a significant impact on performance during training. The evidence of significant sleep disturbance has serious implications for elite level athletes; on its own the level of sleep disturbance has a number of potentially adverse consequences, such as increased risk of infection and illness, compromised metabolism, and sub-optimal recovery from training, potentially serious factors for those training for optimal performance. In addition, the consequences that poor sleep has on training could hamper efforts to prepare properly for elite athletic competition, as well as having a marginal impact on performance itself.

Background. The Association for Physical Education (afPE) recommends that during physical education lessons, students should be physically active for at least 50% of class time. Methods used to determine time spent in MVPA during PE classes should be sensitive enough to capture the sporadic bursts of activity typical of children. However, the extent to which students engage in physical activity is variable, and will be influenced by activity type, school settings, PE structures and gender. Aim. The main aim of this thesis was twofold; first to investigate if type of activity, genders and PE structures significantly influence on children and adolescents PA to meet PE recommendation; second to investigate the influence of natural intervention design in increasing children's PA during school morning break. Method. A series of four studies were conducted to assess children and adolescents PA using accelerometer (in four studies), direct observation (in two studies) and HR monitoring (in one study), with short epochs < 5-s. Results. Data from accelerometers and direct observation are highly comparable, but the validity of HR monitors in PE was questionable. Data from accelerometers and direct observation showed that children were not sufficiently physically active to meet the recommended 50% of PE time. Activity types and genders showed significant differences in children PA levels. Intervention design during break time significantly increased PA levels compared to structured PE and free play during lunch time for both genders.

The ability to regulate energy expenditure during exercise depends upon being able to conceptualise the demands of the task as well as understanding our own physiological limits. Since there is an intellectual aspect to conceptualising task demand, the purpose of this thesis was to explore the importance of cognitive development in children and its influence on exercise pacing strategy. All of the experimental studies in this thesis used a series of conservation tasks to evaluate children's stage of cognitive development. In all of the studies pacing was measured using video analysis to determine average speed at either 5% or 10% segments across a novel running distance. Four experiments were conducted. The first experiment found that a faster relative starting pace was adopted by children between 5-9 years old compared to older children aged 11-14 years old, and that this effect was in part due to differences in cognitive development. In a second study 12- year old children produced a slower pace when a running task was determined using temporal rather than spatial parameters. This effect was due to the conceptually more difficult task of mentally representing time compared to the conceptually easier and visibly tangible parameter of distance. In the third experiment, a slower pace for the first 30% of a 750 m run was recorded among 12-year old children when asked to complete the task on a single large lap compared to five laps of a smaller 150 m circuit. It is concluded that this effect is perhaps due to the larger single track perceptually appearing to be a longer running task. In the final study two-year follow-up data was collected from some of the participants used in study 1, different pacing and improved performance was found among the 5-7 year old follow-up group.

Obesity and insulin resistance are serious health concerns in children and adolescents (young people). Interventions to increase the potential for fat oxidation and improve insulin sensitivity could have widespread clinical relevance. Although exercise is often advocated for health, the factors implicated in the relationship between exercise, fat oxidation and insulin resistance are not well understood in young people. This thesis has investigated the effect of manipulations in exercise and breakfast on metabolism in young people, focusing on fat oxidation and postprandial blood glucose control. The first experimental study, Chapter 4, compared two different exercise protocols for estimating the intensity corresponding to maximal fat oxidation (Fatmax) in non-overweight prepubertal children. A 3 min incremental protocol was recommended to provide an estimation of Fatmax using a wide range of intensities in this population. Using this protocol, Chapter 5 demonstrated that Fatmax was higher for treadmill compared with cycling exercise in pre- to early pubertal children. Furthermore, treadmill exercise resulted in higher rates of fat oxidation over a range of absolute and relative intensities and fat oxidation remained high over a wider range of intensities. Therefore, treadmill exercise (walking or slow running) is clearly preferential for promoting fat oxidation in this population. Subsequently, Chapter 6 examined the effect of mixed breakfast meals containing high (HGI) and low (LGI) glycaemic index carbohydrates on blood glucose, plasma insulin and fat oxidation in overweight and non-overweight girls. Breakfast GI did not affect fat oxidation during the postprandial rest period or subsequent exercise. However, the main finding of this study related to blood glucose; the higher blood glucose response following the HGI compared with LGI breakfast was more pronounced in the overweight girls. This suggested a reduced ability to cope with the metabolic demands of HGI breakfast consumption in overweight girls and highlighted that strategies to reduce insulin resistance in this population are required. Consequently, Chapter 7 investigated the effect of treadmill exercise at Fatmax performed 16 h prior to HGI breakfast consumption on blood glucose, plasma insulin and fat oxidation in overweight and non-overweight girls. Fatmax exercise reduced the postprandial insulin response in the non-overweight, but not the overweight, girls while blood glucose was unchanged in both groups. More encouragingly, fat oxidation was increased after exercise in both the overweight and non-overweight girls. Collectively, the four experimental studies within this thesis have demonstrated that treadmill exercise at Fatmax is an effective means of elevating fat oxidation both during and up to 16 h after exercise. When considering postprandial glucose and insulin responses to HGI breakfast consumption, LGI breakfasts should be recommended for overweight girls, whilst acute treadmill exercise at Fatmax can reduce postprandial insulin concentrations in non-overweight girls. Walking or slow running (Fatmax treadmill exercise) and LGI breakfast consumption may be best advocated in combination for promoting fat oxidation and improving postprandial blood glucose control in young people. These two simple lifestyle-related strategies may provide an effective, safe and attractive means for preventing and treating obesity, insulin resistance and related disorders. Key words: exercise, metabolism, substrate oxidation, fat oxidation, glucose, insulin, glycaemic index, overweight, children, adolescents.

Electron spin resonance (ESR) evidence concerning free radical production by exercise has been confined to animals. This thesis describes a methodology to measure free radicals using ESR in the venous circulation of healthy humans. It also describes three ESR studies of human blood to test the hypothesis that tissue damage associated with strenuous aerobic exercise is free radical-mediated due to the promotion of electron leakage from the mitochondrial electron transport chain via increased whole body oxygen flux, a mechanism known to result in free radical formation. Study l demonstrated a significant increase in the concentration of the α-phenylbutyr-tert-nitrone (PBN) adduct (0.04 ± 0.01 vs 0.18 ± 0.04 arbitrary units, p=0.003) and ascorbyl radical (0.02 ± 0.001 vs 0.03 ± 0.002 arbitrary units, p=0.04) post-exercise. A threshold o fincrease of the PBN adduct appears to exist corresponding to approximately 70% VO2max which may prove to be clinically important. Duplicate blood samples were analysed for lipid peroxidation including malondialdhyde (MDA) and lipid hydroperoxides (LH). MDA (0.70 ± 0.05 to 0.80 ± 0.04 µmol.L-1 p=0.0125) and LH (1.15 ± 0.07 to 1.63 ± 0.29 µmol.L-1, p=0.006) significantly increased post-exercise. Study 1 also demonstrated that exhaustive aerobic exercise results in significant increases in plasma endotoxin concentration (0.16 ± 0.03 vs 0.24 ± 0.06 Eu.ml-1, p=0.001) pre vs post-exercise. This may be a free radical mediated phenomenon also of clinical significance. Study 2 demonstrated that strenuous anaerobic exercise does not lead to increases in the concentration of the PBN adduct or the ascorbyl radical. Furthermore plasma LH did not change in this study although MDA increased significantly (0.74 ± 0.08 vs 1.73 ± 0.65 µmol.L-1, p=0.01) pre vs post-exercise. This may reflect inadequacies in clearance of MDA. Study 3 demonstrated that ascorbic acid supplementation results in an attenuation of the ESR signal both pre and post-exercise. Supplementation with ascorbic acid resulted in attenuation of exercise-induced lipid peroxidation and enhancement of blood arch also demonstrates for the first time a complete abolition of endotoxin from the plasma of subjects who have undergone maximal aerobic exercise. Additionally in vitro studies were performed in order to attempt to identify the origin of the radical species. These results suggest that the ESR signal of the PBN adduct is an oxygen-centred radical possibly derived from peroxidation of membrane PUFA. This work supports The hypothesis that strenuous aerobic exercise leads to increased free radical production probably via enhancement of mitochondrial electron transport chain leakage due to increased whole body oxygen uptake which is detectable using ESR spectroscopy.

The present study looks to evaluate the effectiveness of the meditative practice of Sahaja Yoga as a treatment for the symptoms of anxiety and depression. Whilst there is a small research literature that has investigated the efficacy of meditation (usually based upon the Buddhist Vipassana tradition) for the treatment of such symptoms, and a smaller literature looking at the effectiveness of Sahaja Yoga in the treatment of a number of physical health problems, no published studies have looked at the effectiveness of Sahaja Yoga as a treatment for mental health problems. The present study therefore compared three independent groups, these being a 'waiting list' control group, a cognitive-behavioural (CBT) based stress management group and a Sahaja Yoga meditation group. Both treatment groups consisted of six, two hourly sessions, once per week, with symptom severity being measured at pre- and post-treatment using the Hospital Anxiety and Depression scale (HADs) and the 12 item General Health Questionnaire (GHQ-12). Data were analysed using MANOV A and repeated measures AN OVA tests. The results show that, compared to controls, the participants in the Sahaja Yoga group reported significant reductions on all measures of symptomology, however, surprisingly, the CBT based group showed no such reductions. Limitations of the study, barriers to the use of Sahaja Yoga in clinical practice and the need for future research, particularly regarding process, are considered.

Regular exercise has been identified as being important to an individual's social, physical and psychological well being (Dishman, 1994). Yet very few people exercise to levels sufficient to accrue these benefits. Researchers have begun to develop an understanding of why some people exercise whilst others do not, but much of this research has focused upon non-disabled people, whilst very little is known about disabled people. This research sought to investigate the 'Interactions between Disability and Exercise'. The main aims of this investigation were to first examine the exercise intentions of disabled individual's (wheelchair users) using the Social Model ofDisability (Oliver, 1996), to act as a framework. Secondly, to determine the factors, which underpin intentions to exercise, attitude toward exercise, influence of significant others, choices and self-determination. Critical Social Research (Harvey, 1990), is the process which, is adopted throughout the research in order to examine underpinning factors, which could influence a disabled person's decision whether or not to participate in exercIse.

No description available.