The purpose of this thesis was to explore the role of exercise induced blood flow haemodynamics in the cardiovascular adaptations associated with isometric exercise training, with focus on resting blood pressure adjustment in normotensive participants. Using a cross-sectional study, it was identified that significant relationships were present between (i) blood flow, (ii) shear stress, and (iii) shear pattern responses (measured in the femoral artery), during and immediately following isometric bilateral leg extension exercise of increasing intensity. Based on these findings, it was feasible to suggest that the haemodynamic response to high intensities of acute isometric exercise might provide a physiological challenge to the cardiovascular system, that upon repeated exposure via isometric exercise training, may induce cardiovascular adaptation and resting blood pressure reductions. Subsequent to this, a randomised controlled trial established that performing isometric exercise training to a ‘high haemodynamic stimulus’ did not induce significantly greater adaptation in resting blood pressure than when performing isometric exercise training to a ‘low haemodynamic stimulus’ or control. When the training group (high and low combined) were compared to the control, significant reductions in resting blood pressure were observed. Furthermore, non-invasive cardiovascular variables that were considered as possible physiological mechanisms for resting blood pressure adaptation following isometric exercise training did not correlate with within group resting blood pressure changes. Whilst these findings suggest that a haemodynamic challenge may not be the primary stimulus responsible for inducing resting blood pressure adaptation following isometric exercise training, these results do demonstrate the effectiveness of isometric exercise training for potential health gains via reductions in resting blood pressure in normotensives. Importantly, these findings have progressed the current understanding surrounding isometric exercise training induced resting blood pressure reductions and will allow future research to narrow their focus upon other physiological variables that may be the stimuli for blood pressure adaptation.

The aims of this research programme were to a. Further examine and develop an existing self-report measure of Challenge and Threat within a sport context, b. Examine Challenge and Threat self-report with performance in a sport context, c. Further examine the Biopsychosocial Model (BPSM) proposed in relation to Challenge and Threat and sport performance, d. Examine the associations between Challenge, Threat, cortisol response and sport performance, e. Examine self-report of emotions direction and intensity experienced during a sport performance in regard to Challenge and Threat and f. Examine Challenge and Threat in combination with each other in regard to sport performance. These 6 aims were addressed in 3 different empirical studies. Study 1 used a cross sectional study design to explore the validity and reliability of an existing self-report measure of Challenge and Threat. Participants were gym users (n=200, Mage=24.91) and asked to complete the self-report measure before a dart-throwing competition. Study 2 comprised of three different stages. Stage 1; a cross sectional study design to examine the content validity of a pool of existing self-report items to measure Challenge and Threat in a range of athletes (n=25, Mage=22.00). Participants comprised of male and female athletes engaged in various sports (football, n=6, cricket, n=2, swimming, n=5, tennis, n=1, rugby, n=6, netball, n=3, basketball, n=2.). Stage 2, used a cross sectional study design to further examine the construct validity of the remaining items from stage 1. This stage used principle components analysis (PCA) to determine whether Challenge and Threat self-report items were grouped in a particular way (Kline, 1994). Participants were competitive runners (n=197, Mage=37.11) and asked to complete the self-report measure regarding Challenge and Threat before competition. Stage 3 used a cross sectional study design to explore the validity and reliability of the self-report measure of Challenge and Threat developed in stages 1-2 in competitive runners (n=147, Mage =30.06), using confirmatory factor analysis (CFA) to examine how well the data total fitted the proposed hypothetical model. Finally a quasi-experimental study (study 3) examined the association between Challenge and Threat and shooting performance. This study explored the Challenge and Threat self-report measure and its relationship with performance, emotions and physiological responses. Participants in this study comprised of university student and staff members (n=102, Mage =27.11). Results from study 1 suggested that the existing self-report measure of Challenge and Threat utilised was not suitable for use within a sport context. Results from study 2, stage 1, revealed a pool of self-report items that athletes described as applicable and relevant to their sports performance. Results from study 2, stage 2, suggested that items identified in study 2, stage 1 represented a two component solution, one associated with Threat and the other Challenge. Results from study 2, stage 3 suggested that a 12 item self-report measure was suitable for use within a sport context and that Challenge has a positive association with sport performance. Finally, study 3, suggested that the self-report measure of Challenge and Threat developed in study 2 (stages 1-3) was suitable for use within a sport context. Results from study 3 also suggest that a mixture of Challenge and Threat can have implications for performance outcome. Emotions reported were shown to have associations with Challenge and Threat self-report, as suggested by The Theory of Challenge and Threat States in Athletes (TCTSA). The study findings showed that physiological associations with Challenge and Threat were equivocal. Limitations to the present research programme and directions for future research are discussed.

The main focus of this thesis was to develop an accessible home-based isometric exercise training (IET) protocol for the reduction of resting blood pressure (BP). Hypertension is estimated to affect nearly 30% of the world’s population (WHO, 2012) and represents an inordinate health and economic burden worldwide. A growing body of research suggests that IET can lower resting BP. However, the majority of studies have utilised expensive and/or laboratory-based equipment, which may not be accessible to the general population. To this end, the studies within this thesis explored whether the novel isometric wall squat exercise could be prescribed for home-based training using relatively simple, inexpensive equipment. The first study determined a method for adjusting the wall squat intensity. It was found that knee joint angle reliably produced inverse relationships with heart rate (HR) and BP when individual bouts of wall squat exercise were completed (r at least -0.80; P < 0.05). Study 2 then established that these inverse relationships could be replicated from completing an incremental test (r at least -0.88; P < 0.05), from which wall squat training intensity could then be prescribed at an individualised knee joint angle (104 ± 7°) to elicit a target training HR (95% peak HR: 121 ± 14 beats∙min-1). Finally, using these methods, study 3 implemented a 4 week home-based isometric wall squat training protocol and found statistically significant and clinically relevant resting BP reductions (systolic BP: -4 mmHg; diastolic BP -3 mmHg; mean arterial pressure: -3 mmHg). These results support the majority of previous research that has found reductions in resting BP following IET. Furthermore, the primary BP control mechanisms were also explored and the results suggested that a reduction in resting BP was potentially mediated by a decrease in resting cardiac output (-0.54 ± 0.66 L∙min-1), which may have been governed by a reduction in resting HR (-5 ± 7 beats∙min-1). The novel home-based IET protocol developed within this thesis may be more time and cost effective, which may ultimately increase the adherence to and efficacy of IET for the reduction of resting BP.

This thesis explores America’s fascination with its own sports as purveyors of national identity. American literature has found unique inspiration in sporting competition, not only depicting professional athletes, but drawing from the experiences of fans and amateurs. While the athlete’s heroism and eventual fall has been analysed in previous discussions of this topic, my route of inquiry positions decline and defeat as more central and complex concepts. The focus of this thesis is on the remarkably diverse ways in which contemporary writers reimagine aspects of sporting failure both for their characters and within their own creative process. The centrality of failure seems an affront to the United States’ celebration of success and victory. However, the common strand in the most ambitious contemporary sports writing is to portray experiences of loss and failure as paradoxical routes to self-affirmation. Postmodern writing on sports has taken from the drama and narrative implicit in sporting contest, but uses this framework to question ideas of masculinity, ethnicity, memory and myth. The writers I discuss incorporate failure into these themes to arrive at points of redemptive discovery.

Cycling efficiency is a measure of the ability to convert stored energy into power, and is considered a key determinant of cycling performance. Cycling efficiency has recently been manipulated with various techniques, but most prominently with high intensity training in habitual cyclists and using calorie restriction in sedentary obese participants. It was therefore the primary aim of this thesis to explore the efficacy of utilising a short- and medium-term calorie restriction intervention, to manipulate efficiency with participants accustomed to cycling. A secondary aim was to investigate the validity of measuring efficiency in a field-based environment. Male club level cyclists were recruited for the investigations, which comprised of a moderate -500 kcal.day-1 deficit, utilising portion control and measuring efficiency at both absolute and relative steady-state intensities. Seventeen participants completed the short-term, two-week intervention which utilised a randomised cross-over design. Although a significant reduction in body mass was attained, RMR, gross and net efficiency across all intensities and TT power remained stable. Field and laboratory comparisons indicated that prior to statistical correction absolute efficiency was significantly lower in the field, but after accounting for differences in power, cadence and environmental conditions, no differences were present. Twenty-nine participants conducted the medium-term study and were assigned either to calorie restriction or to no dietary intervention. Following a reduction in mass in the calorie restriction group and an increase in the group given no dietary intervention, a significant interaction between mass and efficiency was found across gross and net efficiency workloads. A six week follow-up period indicated that the process of calorie restriction and not absolute body mass reduction was the main mechanism for altering efficiency. This thesis suggests that efficiency can be manipulated both positively and negatively with calorie manipulation, and that these changes are linked to both laboratory and field based performance.

Isometric exercise training has been shown to bring about beneficial reductions in resting blood pressure, however the physiological mechanism responsible remain equivocal. It is currently unknown whether isometric exercise training-induced reductions in resting blood pressure are associated with improvements in vascular endothelial function and structure. The aim of this thesis was to investigate the effect of an 8-week isometric exercise training intervention on resting blood pressure, conduit artery vascular endothelial function, artery diameter and blood flow patterns at rest. Fourteen healthy young males (mean age: 23 ± 4 years; body mass: 80.7 ± 11.0kg; height: 178.8 ± 6.2cm) completed 8-weeks of isometric bilateral leg extension exercise training at high intensity (105.4% 2-min torquepeak). Three exercise sessions were performed each week and each session consisted of four 2-minute isometric muscular contractions each separated by a 3-minute recovery period. Resting blood pressure was measured using brachial artery oscillometric methods at pre, mid and post intervention. Brachial artery flow-mediated vasodilatation and resting artery diameter and blood flow were assessed at pre, week 2, mid, week 6 and post intervention using high-resolution duplex Doppler ultrasound. Total peripheral resistance and cardiac output were determined at pre and post intervention using high-resolution echocardiography. A generalised estimating equation analysis was used to estimate the effect of exercise versus non-exercise intervention over time on resting blood pressure, brachial artery flow-mediated vasodilatation, artery diameter and blood flow, total peripheral resistance and cardiac output. Isometric bilateral leg extension exercise training reduced resting systolic blood pressure (training: 117 vs. control: 121 mmHg) (P=0.002) and resting mean arterial pressure (training: 88 vs. control: 91 mmHg) (P=0.001) following 4 weeks of exercise training compared to the control condition. Brachial artery flowmediated vasodilatation was increased (mid training: 8.65 ± 1.02% vs. mid control: 6.38 ± 1.14%) (P=0.011). Superficial femoral artery diameter, antegrade blood flow and antegrade shear rate were increased (all P≤0.05), whilst superficial femoral retrograde shear rate was decreased (P=0.013) following 2 weeks of exercise training compared to the control condition. There were no significant condition by time interactions observed in resting blood pressure, vascular endothelial function, artery diameter or blood flow patterns following 8 weeks of exercise training (all P≥0.05). Cardiac output was not significantly different following 8 weeks of exercise training (P=0.148). Total peripheral resistance was increased following 8 weeks of exercise training compared to the non-exercising control condition (P=0.054). Isometric bilateral leg extension exercise training can effectively lower resting blood pressure and increase conduit artery endothelium-dependent vasodilatation in healthy young men after 4 weeks with a concomitant reduction in resting blood pressure. These beneficial adaptations were no longer evident from mid to post exercise training in healthy normotensive young men.