Prosthetic running feet (referred to as Energy Storing & Returning (ESR) or Running Specific Prostheses (RSP) but better known as ‘blades’) take the form of a carbon fibre leaf spring with a deflecting keel component. Available literature on the subject of their dynamic response is limited but suggests that the amputee with running foot can be considered to act in accordance with Simple Harmonic Motion, but this does not appear to be reflected by the prescription processes currently employed by manufacturers. The research question is asked: ‘Is the current method of prescribing prosthetic ESR running feet appropriate and are there additional factors that should be taken into consideration?’ This thesis aims to first understand the static mechanical characteristics of a single model of prosthetic foot; the Flex Run from Ossur (Reykjavik, Iceland). Previous works carried out (that aim to define the energy return efficiency of the devices but results vary from 63% - 100%) are examined and replicated using a series of fabricated jig fixtures, and the disparity in efficiency results is explained. The running action of an amputee is measured using a wearable measurement system that is developed as well as high-speed video capture. The measured action is then replicated in the laboratory using a rig capable of reproducing the dynamic response of the foot. This rig is subsequently used to manipulate the variables of Simple Harmonic Motion and evaluate the suitability of this assumption to model the running action of an amputee. The research concludes by using the gathered learning to create a tool capable of mathematically replicating the response of a prosthetic foot, and the application of such a tool is discussed. It is found during the course of the research that the available Flex Run feet possess an energy return efficiency of >99% and a variable stiffness along the length of the deflecting keel. As a contribution to knowledge, it was also found that during amputee running the ground contact point (and therefore effective stiffness) of the prosthetic changes significantly from foot strike through to toe-off and the profile of this change is defined. As such the principle of a spring-mass system cannot be applied in such a simplistic manner as previously suggested. Furthermore the relationship between amputee mass, stance length, foot deflection and response timing is defined for the first time. It was also discovered that the passive nature of the prosthetic device (and therefore fixed response) has the potential of limiting the top speed of running of an amputee and as such the current prescription method falls some way short of expectations. Methods of improving the prescription process are discussed and further work is suggested to improve the function of these prosthetic devices and therefore the user experience of the amputee athlete.

The cultural lifestyle sport of parkour maintains an ambiguous position at the nexus between deviance and leisure. It conforms to consumer capitalism’s commodified norms of ‘cool individualism’, risk-taking, and the creation of ‘deviant’ identities, whilst remaining a spatially transgressive practice that is continuously excluded by the spatial guardians of the hyper-regulated city. Drawing upon ultra-realist criminological theory and a critical rethinking of leisure, consumerism and urban space, this thesis explains parkour’s ambiguous position by suggesting that there is a fundamental paradox at the heart of parkour’s spatial practice that is a product of late-capitalism’s own making. As Post-Fordist Western societies shifted toward a consumer-oriented economy, consumer capitalism had to stoke the desire for cool and alternative identities such as parkour that tapped into subjectivities increasingly oriented to socio-symbolic competition and individualistic distinction. Simultaneously, deindustrialised cities were regenerated through the commodified urban leisure economy, prompting a renewed reliance upon hyper-regulated urban spaces to harness and direct desire and identities and consumption into these commodified spatial contexts. Consequently, this thesis argues that the paradox of parkour is a dual-product of late-capitalism’s cultivation of subjectivities geared to the pursuit of unique and culturally relevant identities, and a consumer economy that is reliant upon the hyper-regulated specificity of central consumer spaces. Consequently, consumer capitalism is caught in the double-bind of simultaneously promoting parkour whilst attempting to prohibitively direct it into approved and commodified spatial contexts. This is a paradox that has been entirely neglected in the academic literature on parkour, due in large part to the fetishisation of parkour as a form of ‘resistance’. This thesis challenges this fundamental assumption, drawing upon 28-months of in-depth ethnography among a parkour community in the North East of England. It accesses the wider life-worlds of traceurs, following them not only through their illicit practice of parkour in the city, but through their attempts to ‘make it’ in the commodified and professional world of parkour, cultural lifestyle sports, and social media fame. It explores the desires and motivations at the heart of the traceurs’ practice and their attempts to preserve a sense of culturally-relevant identity while navigating the precarious waters of early adulthood in late-capitalism. Additionally, the thesis utilises walking interviews with security guards to supplement ethnographic observations around spatial governance, systemic spatial violence and the amoral economy of late-capitalist cities. As such, the thesis provides a critical rebuke to the romanticisation of parkour as a mode of proto-political resistance, and instead attempts to explain its ambiguous position in the deviant-leisure nexus through an in-depth analysis of urban change, consumer culture, and identity in late-capitalism.

The aim of this study was to provide a comprehensive analysis of key biomechanical variables in race walking through the analysis of elite athletes in both competitive and laboratory settings. Video data from two 3CCD camcorders of athletes competing over 10 km (juniors only), 20 km, and 50 km were collected at three international competitions. For the 20 km and 50 km events, multiple recordings were made to identify if kinematic changes occurred. In addition, synchronised high-speed video, electromyography and ground reaction force data were collected of 20 elite race walkers in a laboratory setting and combined to calculate joint moments, power and work. The key discriminants with regard to better performances were long step lengths and high cadences, and the contribution made by flight distance to step length (approximately 13%) was particularly important, regardless of race distance or age category. Step length ratio was a better predictor of optimum step length than absolute values and a ratio of about 70% was found in the fastest athletes. Although reductions in step length and flight distance were a major cause of decreased speed over both 20 km and 50 km, many gait variables did not alter greatly, showing that these elite athletes were able to maintain their techniques despite fatigue. The foot position ahead of the body at initial contact (approximately 20% of stature) need not be detrimental to fast walking if the athlete has the strength to overcome the potentially negative effects; instead, it can be beneficial to increase this distance in achieving a greater step length and could be a key area for women in particular to develop. The hip muscles were the main source of energy generation, with both flexors and extensors doing more positive work than any other muscle group (22.4 ± 7.1 J and 42.3 ± 10.1 J respectively), although the ankle plantarflexors also generated considerable energy before toe-off (16.4 ± 3.8 J). A hip extensor moment that occurred during late swing and early stance helped maintain forward momentum as it reduced the braking peak force and duration of the negative anteroposterior force. The knee had little involvement in energy generation because of its predominant role as a rigid lever during stance, and absorbed considerable energy during swing (–46.4 ± 9.5 J). However, its abnormal movement that was dictated by the race walking rule also had an important role in maintaining contact with the ground and reducing vertical forces so that visible loss of contact was avoided. The study was the first to analyse in such depth the biomechanics of elite male and female race walkers across all competitive distances and its results could be used to develop a technical manual for this Olympic event and greatly impact on coaching practice.

Physical activity helps maintain health, promotes adaptations of the cardiovascular and neuromuscular systems to increase uptake, transport and utilisation of oxygen for aerobic energy production and improve fatty acid metabolism. Emerging evidence suggests sprint interval training (SIT) may be as effective as endurance exercise. The overall aim was to measure physiological effects of SIT in males and females from the general population. The first objective was to recruit males and females from the general population to complete 12 weeks cycling SIT and monitor changes relating to health and physiological function. The primary outcomes were changes in body fat mass, VO2max, FATmax, knee extensor muscle size, strength, power, fatigue resistance, circulating concentrations of lipoproteins and inflammatory markers. The secondary outcome was a comparison of results between males and females. The second objective was to recruit Masters sprint and endurance runners to complete measurements of health and physiological function. The primary outcomes were peak power output and VO2peak in one and two-leg cycling. After 12 weeks SIT, females showed higher increases (18.7%) in VO2max (ml/kg/min) than males (6%) (gender comparison: p=0.009), males exhibited greater body fat (%) reductions (1.5%) than females (0.1%) (gender comparison: p=0.015). Males and females had similar increases in knee extensor fatigue resistance (4.0% and 8.9% respectively, gender comparison: p=0.221) and muscle cross sectional area (CSA) (cm2) (4.1% and 5.8% respectively, gender comparison: p=0.895). Neither gender showed changes in circulating inflammatory proteins, but LDL decreased in males (7.8%) and females (3.7%) (gender comparison: p=0.161) and the ratio of cholesterol:HDL improved in females (13.1%) and males (19.6%) (gender comparison: p=0.523). Master sprint athletes had 22% higher peak power output (W/Kg) than endurance athletes (discipline difference: p=0.045), but endurance master athletes have 17% higher VO2peak (ml/kg/min) (p=0.012) and 30% higher FATmax (mg/kg/min) (discipline difference: p=0.041). The inverse relationship between VO2peak, FATmax and peak power with age was similar (10-12% per decade) for sprint and endurance athletes. It is concluded that males and females adapt positively to SIT, although gender differences in VO2max and changes to body fat were found. Despite differences between masters endurance and sprint athletes in FATmax, VO2peak and peak power, age related decline is similar in both disciplines.

The literature pertaining to the development of maximal sprint performance in male youth is sparse. Existing literature suffers from a combination of small sample sizes, a lack of control for the influence of maturity, methodological approaches where maximal speed is not measured or failure to explore the spatiotemporal, kinematic or kinetic characteristics associated with sprint performance in male youth. On this basis, the aim of this thesis was to investigate the influence of growth and maturation upon maximal overground sprint performance in a large cohort of 11-16 year old boys. Sprint and spatiotemporal variables were found to have acceptable reliability (CV = 3.8-12.6%). Cross-sectional analysis of a large sample of boys showed a maturational effect on sprint performance, with the period of peak height velocity (PHV) eliciting the greatest enhancements in maximal sprint speed. Furthermore, whilst improvements in step length (SL) were observed with increasing maturity, step frequency (SF) was largely stable, with some evidence of small declines during the pre-PHV period. Further cross-sectional analysis revealed that pre-PHV boys were SF-reliant during maximal sprint performance, whilst post-PHV boys were deemed SL-reliant. Analysis of body size revealed that stature had a positive influence upon maximal sprint performance, whilst mass had a negative influence. Cross-sectional analysis of the kinetic characteristics of maximal sprint performance revealed that both relative maximal force and relative vertical stiffness did not increase with advancing age and maturity, but these variables were deemed to be the most important predictors of maximal sprint performance in male youth, independent of age and maturity. Furthermore, longitudinal analysis confirmed that relative force production and relative vertical 4 stiffness were the most important predictors of maximal sprint performance in boys, and that those who had passed the period of PHV experienced greater gains in maximal speed than those who remained pre-PHV. Collectively the results of the empirical studies highlight that maximal sprint speed in male youth develops with advancing age and maturation, due to an interaction of changes in SL and SF. These changes are partly related to changes in body size and the period of PHV appears to be a key period during the development of maximal speed. However, there are also key predictors of speed, such as relative force and relative vertical stiffness that do not change between the ages of 11 and 16 years old.

Elite athletic performance is widely acknowledged to result from the exposure of a favourable genetic endowment to a favourable combination of environmental factors including culture, diet, training regime and socioeconomic status. Athletes from West African descendant populations in North America and Western Europe have long been prominent in elite sprint running, constituting 63% of the top 100 performers in each sprint discipline, outperforming athletes from Europe (23%), West Africa (8%) and the rest of the world (6%). These members of the West African diaspora are genetically admixed, resulting in detectable levels of both African and European ancestry because of gene flow between African slaves and Europeans during chattel slavery in the 16th to 19th centuries. The overall aim of this thesis was to investigate the effect that ancestral genetic composition may have had on the likelihood of becoming a top-class sprint athlete amongst samples of African-Americans and Jamaicans. It was hoped that these findings would add to the existing research in attempting to understand the unique combination of factors that produce elite sprint athletes. Ancestrally informative genetic data from elite African-American and Jamaican sprint athletes and ethnically-matched controls were used to explore how genetic ancestry affects sprint athlete status in these populations. These data are also vital when investigating the putative origins of an admixed population, and relatively little research has investigated the genetic ancestry of modern Jamaicans when compared to African-Americans. To bring the two groups to comparable levels of insight, the population history of the Jamaican people was estimated by comparing the observed matrilineal gene pool to the gene pools of known source regions of Africa. By simulating a stable population with the observed population dynamics from slave-era Jamaica, it was possible to draw conclusions about selection acting on the Jamaican slave population from the colonisation of the island by England in 1655 until the abolition of the slave trade in 1807. In addition to the Jamaican maternal lineages already genotyped, paternal lineages in both African-Americans and Jamaicans, as well as maternal lineages in African-Americans were genotyped to assess any association these lineages had with elite sprint athlete status. These lineages were also compared between the cohorts to assess any differences in lineage composition across both groups of athletes and controls. Finally, locus-specific genetic ancestry was calculated to map loci associated with elite athlete status to regions of the genome with a greater amount of African or European ancestry than would be expected under the null hypothesis of no association with ancestry. Assuming a difference in the likelihood of sprint athletes originating from either Africa or Europe, detected associations between locus-specific ancestry and sprint status may indicate specific genomic regions of interest. The main findings of this thesis are: a) Modern Jamaicans are mostly descended from slaves originating from the Gold Coast of Africa, despite large influxes of slaves from the Bight of Biafra and West-central Africa before the end of the slave trade. b) There appears to have been selective pressure acting on the slave population of Jamaica. Differences between the presumptive origins of the observed lineages and the outcome of the stable population model suggested varying levels of mortality and fecundity within the slave population, consistent with earlier ethnographic and linguistic studies. c) The distribution of maternal lineages in the African-American athletes were significantly different from that of African-American controls. Maternal lineage distributions between Jamaican athletes and Jamaican controls were not significantly different. There was insufficient statistical power to infer any differences between the paternal lineages of African-American athletes and controls or the Jamaican athletes and controls. This suggests that either maternal ancestry may be a factor in elite sprint athlete status for African-Americans or it could simply be a false positive, inherent to the methodology used. Jamaican maternal lineages are homogeneous with regards to elite sprint athlete status. There was insufficient statistical power to arrive at similar conclusions regarding the paternal lineages of athletes and controls in either group. d) The maternal lineages of African-American athletes and Jamaican athletes were significantly different, although there was insufficient statistical power to determine if there were any differences between the paternal lineages of African-American athletes and Jamaican athletes. This suggests that the same maternal lineage distribution is not associated with sprint athlete status in the two populations, while there is insufficient evidence to make a similar claim regarding paternal lineages. e) The maternal lineages of African-American controls and Jamaican controls were also significantly different, although there was insufficient statistical power to conclude whether significant difference exists in the paternal lineages of African-American controls and Jamaican controls. These results suggest that there is some evidence that the population histories of African-Americans and Jamaicans are significantly different despite the lack of evidence from the paternal lineages. f) The proportion of genome-wide African ancestry did not differ significantly between either African-American athletes and controls or Jamaican athletes and controls. This suggests that environmental factors typically associated with higher levels of African ancestry in these populations (e.g. lower socioeconomic status, diminished access to healthcare) are not directly linked with elite athlete status. g) The estimated number of generations since admixture occurred did not differ significantly between athletes and controls for either African-Americans or Jamaicans. This suggests that athletes were not more likely than controls to have had European ancestors in the recent past, thereby potentially having greater access to resources. h) Admixture mapping was used to detect an enrichment of European ancestry at chromosome 4q13.1 significantly associated with athlete status in African-Americans. There were no significant loci associated with athlete status in Jamaicans. This suggests that the regions of the genome influencing sprint athlete status may be different in the two populations, although there was insufficient statistical power to draw any meaningful conclusions from the Jamaican data. This thesis has potential implications for future work not only explaining the disproportionate success of West African descendant sprint athletes but also for advancing the basic understanding of the genetic influences on the limits of human performance.

The aims of this thesis were to: 1) to review research in the area of repeated sprint (RS) performance and diurnal/circadian rhythmicity; 2) to develop a new RS protocol that conforms to field based team sport time-motion analysis and determine its reliability and compare this with a RS protocol previously utilised in the literature; 3) to assess the sensitivity of the RS protocol following acute altitude exposure and simulated soccer specific exercise 4) to investigate diurnal variation of RS performance and assess whether modulating rectal and/or muscle temperatures lead to changes in RS performance. A review of the published research literature investigating the relationship between RS performance and time-of-day variation was conducted. Six studies made it through the whole analysis process for systematic review. It was established that there was evidence to support a late/early afternoon peak in peak power in RS performance around the peak of the rhythm of core temperature. However, there is a clear demand for more rigorous investigations which control factors specifically related to chronobiological investigations. A reliability study was then performed using running as the mode of exercise for the RS test using two different RS protocols to determine the number of trials required to establish high levels of reliability. The first RS test (consisting of a total of 10 sprints, 6-s in duration with 30-s of passive recovery) was a commonly used protocol in the literature and the second was a newly created RSA protocol which is better representative of field based team sports activity (consisting of a total of 10 sprints, 3-s in duration with 30-s of passive recovery). It was established that a number of performance measures of RSA non-motorised treadmill running in both protocols were reliable. However, measures of fatigue were not. Further, it was found that both protocols took 3 sessions to fully familiarise individuals. The main aim of the next study was to investigate the sensitivity of the RSA protocol by examining the effect of altitude and fatigue on RS performance. The first finding was that acute altitude exposure reduces RS performance by 3.1 to 6.5% at 1500-m and 6.2 to 12.8% at 3000-m. The second finding was that RS performance was reduced by 4.6 to 5.8% in a fatigued state. The newly created RS performance protocol is sensitive enough to detect a negative change following altitude acute exposure and a 90-min football-specific intermittent treadmill fatiguing protocol. A diurnal protocol was then employed in order to address the clear demand for more rigorous investigations in chronobiological studies of RS performance. A total of 20 participants took part in this study and it was found that RS performance was significantly higher in the evening compared to the morning ranging from 3.3 to 8.3% in all measures except fatigue index. Diurnal variation now established in RS performance, two studies assessed whether modulating rectal and/or muscle temperature leads to a change in RS performance and further determine how much can be attributed to the influence of an endogenous, temperature-dependent component. The first study (n = 12) established that raising morning rectal temperature to evening values by active warm-up did not increase RS performance to evening values. However, lowering evening rectal or muscle temperatures to morning values by pre-cooling decreased RS performance to values normally observed in the morning. The second study (n = 12) found passively raising morning rectal temperature to evening values, or passively raising morning and evening rectal temperatures to 38.5ºC did not increase RS performance nor offset diurnal variation. Both studies concluded that although central temperature may provide some endogenous rhythm to RSA, the exact mechanism(s) for a causal link between central temperature and human performance are still unclear, and may involve multiple of components and mechanisms.

The study examines a particular aspect of the development of athletics in Scotland. The first organised clubs for the sole purpose of purely athletic competition in the contemporary sense, were cross country clubs known as harrier clubs. Through investigation of the origins, governance and the social structure of harriers clubs, the study connects these three fundamental themes in understanding sport within broader social historical study. In this study the origins of cross country running are set within a theoretical framework which recognises the nature of the urban and rural environments which defined the sport. The sport’s early growth and governance in Scotland is set alongside the broader ideological position of the ‘amateur’. Additionally, club organisation promoted the clubs as cultural institutions. Clubs served as a focus for male sociability and elevated the status of membership of the harriers. Membership meant more than just sporting engagement; it included social and civic standing. The purpose and function therefore of early clubs extended beyond participation. This study demonstrates how membership of cross country clubs conferred upon its members a status, establishing harriers clubs as important social institutions. This research shows how social networks within sport replicated society more broadly. The significance of the contribution of cross country clubs to the development of Scottish sporting culture is therefore implicit. Harriers clubs were the epitome of the complexity of sporting engagement representing both respectability and liminal behaviour.

The aim of this research was to specify and develop a service that is capable of delivering personalisable running shoes with mass appeal. Current sports footwear personalisation services focus primarily on aesthetic design via the internet. Aesthetics do not appear to be the consumers primary interest when purchasing running shoes and a large number are also reluctant to purchase online; preferring to purchase from specialist running stores where they receive the advice needed and can directly interact with the product. After reviewing the literature, it was hypothesised that the implementation of a primarily comfort and performance running shoe personalisation service with an in store fitting element, utilising additive manufacturing as an enabling technology, would give the greatest opportunity for success. Survey methods and store visits were employed that targeted both qualitative and quantitative data, exploring consumer running shoe purchase preferences, running shoe use and opinions of current personalisation services. The findings from these studies supported the previously stated hypothesis and enabled the specification of a suitable service. Subsequently, the focus of this research was the development of a toolkit, a computer-based system that enables the consumer to make their selections, the core of most of the current services. Experts in biomechanics and additive manufacturing were consulted to ensure that a feasible yet innovative solution was delivered. The resultant toolkit prototype (www.yourstep.co.uk) was tested formatively, using multiple methods and summatively with a large sample. Using the toolkit was considered an enjoyable, intuitive experience; a large percentage (69%) of summative testing participants would consider purchasing personalised running shoes using this method. The approach adopted to specify and develop this service provides a framework, based upon empirical research, for those looking to implement a practical running shoe personalisation service that meets their consumers requirements.

It is common practice for endurance athletes to manipulate training load prior to an important competition, known as tapering. An effective strategy aims to alleviate accumulated fatigue, whilst maximising physiological adaptation and facilitating a peak performance. Improvements in performance of 0.5 to 6.0% have been reported after a successful taper, a margin that could potentially have a dramatic influence on performance outcome at the elite level. This thesis explored the strategies currently employed by elite endurance athletes and investigated novel training manipulations during the taper to further enhance performance, to gain a more thorough understanding of the physiological mechanisms, and to identify a minimally invasive physiological biomarker capable of monitoring recovery status during the taper. Tapering strategies in elite endurance athletes were shown to be individualised and influenced by the preceding training load. Algorithms were developed, capable of explaining a large proportion of the variance (53-95%) in tapering strategy training variables (with the exception of interval volume), for a given pre-taper training load (Chapter III). A tapering strategy implemented using the algorithms was most likely to improve 1,500 m treadmill performance (ES = 0.53). When the intensity of final interval session was increased from 100% to 115% race speed, the effect on treadmill performance was unclear (ES = 0.22) and perhaps due to insufficient recovery to respond positively to the increased intensity interval session (Chapter IV). When continuous volume was reduced further (by 60%), the novel high intensity strategy was very likely to improve 1,500 m track performance (ES = 0.74), compared to the algorithm-derived taper (ES = 0.40) (Chapter VI). In middle-distance runners, training above race speed in the final days of the taper might be more beneficial than current practice, although training volume must be further reduced to compensate. It was possible to measure plasma concentrations of interleukin-6 and soluble interleukin-6 receptor from capillary samples (Chapter II), although these markers in addition to C-reactive protein, testosterone and cortisol were not sensitive enough to detect changes in recovery status during tapering (Chapters IV and V). Measures of muscle maximum voluntary contraction force (algorithm-derived taper: 9%; ES = 0.39; novel taper: 6%; ES = 0.29), and rate of force development (algorithm-derived taper: ES = 0.53; novel taper: ES = 0.26) improved in response to tapering (Chapter IV), and could represent alternative non-invasive markers of recovery and taper effectiveness to facilitate peak performance.