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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The effect of neoprene athletic supports on cricket bowling and javelin throwing

Hurrion, Paul David January 1997 (has links)
This study investigated the technique of the individual, using an integrated biomechanical approach, to assess injury potential and performance. The effects of five neoprene athletic supports were investigated for the cricket bowl and javelin throw. A significant improvement in distance thrown and an increase in linear speed of body segmental movements were found for a lumbar support belt during the javelin throw. A two-handed overhead throwing activity was designed to investigate the effect of this lumbar support belt during the hyperextension - flexion movement of the torso. Significant differences in the distances thrown and segmental timing during the belt condition were found for both novice and experienced athletes. An integrated approach (three-dimensional cinematography, ground reaction forces and electromyography) was then used to analyse the effect of this lumbar support belt during the delivery phase of both sporting activities. The rate at which the torso uncoiled, (the relative peak shoulder to peak hip speed) was found to be significantly different during the belt condition for both activities. The results of these experiments suggest that the lumbar support belt enabled a more efficient transfer of speed to the upper body. A significant improvement in distance thrown during the lumbar support belt condition was found for the javelin throw.
52

Biomechanical investigation of subtalar joint action in normal and pathological gait and the modifications induced by functional orthoses

Robinson, Ian January 2003 (has links)
Current techniques of rearfoot alignment measurement have been reviewed and a new clinical technique of rearfoot measurement in weight bearing stance has been developed. This technique was validated by radiographic and cadaveric anthropometric studies. The relationship between a central heel bisection line and the underlying bone structure was investigated, and showed that the heel bisection line was coincident with the centre of the x-ray image of the calcaneus at its upper margin, but appeared to be skewed to the lateral side of the image of calcaneus (to 40% of its width) at its lower margin. A cadaveric study confirmed that this appearance arose as a result of a calcaneal tubercle that is larger medially than it is laterally. Reliability of rearfoot measurement was investigated and showed good repeatability (within the 0.5" resolution of the instrument) when made by an experienced podiatrist, with intratester repeatability of 0.93 and 0.95.
53

Imidazole dipeptides : dietary sources and factors affecting uptake and muscle content

Jones, Glenys A. January 2011 (has links)
The imidazole dipeptides (ImD); anserine (Ans), carnosine (Cam) and balenine, have been shown to be effective at functioning as H+ ion buffers, with Carn being particularly effective within the physiological pH range. Therefore ImD have been reported to be beneficial to athletes exercising at high intensities, where the activity results in the production and accumulation of H+ ions within skeletal muscle. It has also been hypothesised that these compounds may also be beneficial in reducing the morbidities related to ageing, such as Alzheimer's disease. Humans store ImD in the form of Carn and not as anserine or balenine. However, within the human body Carn production is limited by the ability to degrade uracil in the liver, with 3-alanine being the limiting factor. Therefore the content of the diet has a substantial impact on the level of Carn within human skeletal muscle. This thesis aimed to investigate the variability in ImD with age and in subjects from different geographical locations. The effect of ageing on the muscle content of the ImD was demonstrated through the use of a murine model, where increased age was accompanied with a 45% decline in the ImD levels measured in the tibialis anterior of 60wk old senescence-accelerated male mice (Chapter 9). This is supported by further work (Chapter 14) which showed that elderly European subjects exhibited lower levels of carnosine in the vastus lateralis compared to younger European subjects (15.6mmol·kg-1 dm and 22.4mmol·kg-1 dm respectively). However, in Korean elderly subjects no decline was observed (21.5mmol·kg-1 dm), and this could potentially be explained by different dietary habits, with the elderly Korean subjects consuming larger amounts of protein-rich foods than their European counterparts. Analysis was made of the variation in the carnosine content of the vastus lateralis in subjects from differing geographical locations, and subsequently different cultural diets with varying meat contents, and showed that dietary intake of a diet habitually rich in the ImD could potentially 'over-ride' the decline seen with age in subjects who 'reduce' their meat intake.
54

The acute and chronic effects of isometric exercise on haemodynamic, autonomic and cardiac function in a pre-hypertensive population

Taylor, Katrina January 2017 (has links)
Raised blood pressure (BP) remains the leading modifiable risk factor for cardiovascular disease morbidity and mortality globally. As such, primary prevention strategies are required to improve risk factors to prevent the development of hypertension (HTN). Isometric exercise training (IET) is becoming an established intervention for reducing resting BP. However, few studies have investigated the effects of IET in a population at increased risk of developing HTN. Therefore, this thesis examined the effects of IET, using a novel home-based wall squat intervention, in a pre-hypertensive male population. Specifically, the thesis aimed to explore the potential mechanism/s responsible for improved BP control using an acute isometric exercise (IE) stimuli and a four-week IET intervention. Firstly, acute IE was shown to elicit a step-wise increase in BP, heart rate and cardiac output and associated increase in sympathetic activity. In the immediate recovery period, there was a hypotensiveresponse, which was associated with parasympathetic activation, increased baroreceptor reflex control and reduced peripheral vascular resistance. The hypotensive response was also associated with improved indices of cardiac function, including a reduced estimated filling pressure. Four weeks of IET was shown to significantly reduce resting and ambulatory BP. Improved autonomic cardiovascular control, with increased parasympathetic over sympathetic activity, greater baroreceptor reflex sensitivity and reduced peripheral vascular resistance potentially mediated the decreased BP. A reduction in plasma interleukin-6 and asymmetric dimethylarginine suggests an anti-inflammatory response and improved vascular function, respectively, following IET. Finally, improved myocardial diastolic function suggests positive cardiac adaptations in response to BP reductions. Collectively, the findings of this thesis highlight potential mechanistic pathways for improved BP control in a prehypertensive population and demonstrates wider cardiovascular benefits of IET beyond BP reductions, which are important observations for risk reduction in this population.
55

Optimising whole-body fat oxidation in humans

Corbett, Jo January 2007 (has links)
Increasing the amount of energy derived from fat is likely to have important health and performance applications. This thesis applied contemporary knowledge in order to investigate strategies for optimising whole-body fat oxidation, in male subjects. Study 1 investigated the efficacy of Xenadrine EFXTM (Gx), a weight-loss supplement containing bitter orange, green tea, and guarana, in promoting fat metabolism during 6 h rest. The ingredients in Gx are purported to increase lipolysis and fat oxidation. Indeed, a metabolic effect of Gx was evident. However, carbohydrate oxidation was increased by 15.5 ± 5.6 g over the 6 h period with a concomitant decrease in fat oxidation of -5.9 ± 3.1 g, while the metabolic rate remained unchanged. Study 2 extended the work from the first experimental study, by examining the acute effects of GX during 60 min sub-maximal treadmill walking. Although the onset of the walking exercise resulted in an approximately five-fold increase in the rate of fat oxidation, a reduction in the energy derived from fat, and increase in the energy derived from carbohydrate, was again evident with Gx. In Study 3 the intensity of exercise was manipulated, during treadmill running, in order to determine the exercise intensity eliciting the highest rate of fat oxidation (Fatmax). There was a large variation in the rate of fat oxidation across the range of exercise intensities investigated, with Fatmax occurring at 65.9 ± 1.0 % V02max, while individual peak rates of fat oxidation were 0.54 ± 0.04 g·min-1. This study highlighted the need for careful consideration of the intensity of exercise in order to optimise fat oxidation. Study 4 identified a relationship between Fatmax and the lactate threshold, during treadmill exercise. Analysis of plasma glycerol and NEF A concentrations indicated that the reduced rates of fat oxidation at high exercise intensities were not mediated by reduced lipolysis or plasma FA availability. These finding's were interpreted as supporting either depletion of the free carnitine pool, or inhibition of CPTI by a reduction in intra-cellular pH, as mediating the reduction in fat oxidation at exercise intensities in excess of Fatmax. Based upon the hypothesis that a reduction in intra-cellular pH might contribute to the reduced rates of fat oxidation at high exercise intensities, Study 5 sought to increase intra-cellular H+ buffering capacity. Four weeks supplementation with ~-alanine resulted in a significant increase in the muscle concentration of carnosine, an imidazole dipeptide contributing to intra-cellular physico-chemical H+ buffering. Despite the augmented carnosine concentration there were no changes in substrate utilisation across the range of exercise intensities studied, whilst Fatmax remained unchanged. This data suggests that a reduction in intra-cellular pH does not mediate reduction in fat oxidation during intense exercise. Taken together, the findings of this thesis demonstrate the importance of exercise as an intervention for facilitating fat metabolism, and highlight the primacy of carbohydrate metabolism within the fat-carbohydrate interaction.
56

An investigation into the importance of off-horse exercise on riding position of horse riders

Prentice, Jaana A. A. January 2016 (has links)
In equestrian science, anecdotal evidence suggests that certain fitness parameters are beneficial for riding position. Studies have investigated the demands of riding; however, there is no objective data linking the general fitness of riders to its effects on riding position. This research set out to investigate the perceived importance of off-horse exercise on riding position, the impact that certain fitness parameters have and the effectiveness of a specifically tailored exercise programme. Nearly 90% of respondents stated they believed off-horse exercise to impact on their riding position, with dressage, leisure and older riders to be most likely to participate. The average fitness of riders including aerobic capacity, core stability, balance, flexibility and posture was then researched regarding the effect these might have on riding position. In a cross sectional study the relationship with riding position and pressure distribution, looking at the laterality of the seat, were explored. With the exception of cardiovascular fitness these were then tested for transferability of skill in an intervention trial. A mechanical horse and video analysis were used for analysis and the TekScan pressure mat recorded pressure distribution. Aerobic capacity was found to have no impact on riding position in this study and hip flexibility was assumed to have the greatest impact on riding position. After the intervention, the range of motion of the angles was decreased suggesting a more stable and quiet seat due to increased core stability. In line with other research asymmetries in the rider were found in pressure distribution, which were significantly decreased post intervention (trot and canter). No improvements in medio-lateral symmetry were found. Transferability of skill in riding position can be explained with the high similarity of standing posture and riding position. Overall horse rider specific training regimes can be recommended for improvement of riding position, but combination with riding instruction is suggested.
57

Determinants of elite rowing performance : implications for developing rowers

Homer, M. R. January 2014 (has links)
Olympic Rowing is a ‘power endurance’ sport with a range of anthropometric, physiological and technical requirements. Literature examining the physiological determinants of elite rowing performance has rarely included the analysis of different groups or their longitudinal development. Elite rowing traditionally adopts a ‘squad based’ approach to training which often fails to recognise the potential benefits of individualised training. To date, limited data exist examining the individualised profiling of elite rowers leading to the inclusion of bespoke training prescription in order to maximise performance. Study 1 investigated the relationship between 2,000m ergometer performance and regularly monitored physiological variables, which contribute to selection, in male and female elite senior and development rowers. Analysed individually, there were large differences in the relationships observed across gender and competitive level, with submaximal aerobic capacity (power at 4 mmol・l-1 lactate; W4mmol・l -1) being the only variable to significantly correlate with 2,000m performance in all squads. Results were further analysed using bivariate regression to examine the degree of shared variance between physiological status and performance. W4mmol・l -1 was able to explain 25-59% of the variation in performance. Other variables were able to explain the variance in performance to differing degrees, depending on the squad. This suggests that coaches and practitioners should examine performance determinants of homogenous groups, as the determinants of performance may be different depending on gender and competitive level. Study 2 investigated the importance of W4mmol・l -1 by tracking its longitudinal development in a large group of elite male rowers completing the same training programme. Changes in W4mmol・l -1 were analysed in order to investigate progression rates and differences between Olympians (OLY) and non-Olympians (NON). OLY improved significantly following each of the first 3 years of elite level training. The results of a case series analysis of individual athletes, including a double Olympic gold medallist with >12 years of international experience, suggested a clear upward trend in W4mmol・l -1 throughout a career, despite fluctuations within individual seasons and Olympiads. Improvements were attributed to the physiological adaptations associated with a consistent and well executed high volume/low intensity training model. Differences in the development of W4mmol・l -1 between OLY and NON were not significant until the 3rd year of elite level training. The stagnation in W4mmol・l -1 observed in NON athletes at this time was ascribed to a ceiling of aerobic development or an inability to effectively polarise training in order to maximise adaptation. At this point alternative training methods could be introduced in order to avoid stagnation in development and subsequent performance. Physiological profiling during the early stages of an athlete’s career could also identify those more likely to thrive in a high volume/low intensity training programme. Study 3 involved the implementation of a physiological ‘Spider Profile’ for club rowing coaches. Using key performance determinants, development athlete’s relative strengths were identified in order to inform the training process. Results were compared to senior athletes and ‘Olympian Standards’. U23 international athletes possessed significantly greater maximal and sub-maximal ‘rowing specific’ endurance capacities than noninternational rowers, and were significantly weaker than senior athletes in measures of maximal strength. It was therefore suggested that in order to improve their chances of U23 and senior team selection, development athletes should prioritise the improvement of technical and aerobic indices of performance rather than strength and power. Also, the identification of new athletes should be weighted more towards endurance factors than maximal strength and power production. Study 4 refined the physiological profiling system developed in the previous studies and used it to implement training interventions that improved individual weakness in a group of six elite male rowers. Athletes were assigned to either an endurance (END, N=4) or maximal power (MAX, N=2) group depending on the results of a complete physiological profile. All rowers completed a generic rowing training programme (mean volume = 131 km per week) with 2 of the 14 sessions per week comprising either high intensity aerobic interval training or additional weight lifting. Results were analysed as a case series with individual responses discussed as a lack of control group made the relative impact of training interventions difficult to assess. Three out of four END athletes improved aerobic indices, in particular V&O2peak, but made no improvements in markers of power production. MAX athletes improved their maximum power and aerobic performance. This was attributed to increased mechanical efficiency, muscle coordination and recruitment, strength related technical improvements and/or the reduced relative intensity of sub-maximal work leading to conservation of energy. In conclusion, the minor adaptation of a generic rowing training programme can have a marked effect on the physiological adaptation of athletes struggling to make progress in a traditional high-volume/low-intensity system. In summary, this thesis has highlighted that the analysis of heterogeneous groups of rowers does not provide the level of detail necessary to describe elite performance. Instead, due to individual differences in determinants of performance, a case series approach is a more appropriate means of identifying strengths and weaknesses and implementing interventions to make improvements. Aerobic indices of performance are highlighted as the most important descriptors at both a development and international level. In particular sub-maximal capacity, which is superior in elite development athletes, can be used to differentiate between those that achieve senior team selection, Olympic success, and those that fail to reach the upper echelons of the sport. Spider Profiles are an effective tool which highlight individual strengths and weaknesses in development athletes. Such profiles can be used to provide bespoke interventions to individuals failing to make an impact in elite rowing teams, and the subsequent improvements made can have a global effect on performance if they can be applied to the rowing stroke effectively.
58

An investigation into the sleeping patterns of youth soccer players during the competitive season

Turner, C. January 2016 (has links)
Sleep is a recurring state that is considered a critical process in the optimal attainment of daily functions and recovery in athletes. However individuals from elite sports, such as soccer, may be exposed to a number of situations that may impact sleep within the competitive season (such as inconsistent schedules and travel), which may result in sub-optimal sleeping patterns. However, research documenting the sleep of soccer players is at present limited. Therefore it would seem important to investigate how soccer players sleep to further the understanding of how sleep may be impacted. On this basis, the aim of the current thesis was to examine the typical sleeping patterns of youth soccer players and the factors effecting sleep. This was completed through a series of investigations conducted during the competitive youth soccer season. The aim of the first study (Chapter 3) was to validate a commercially available wireless sleep-monitoring device (WS). This was done in an attempt to provide a viable methodology to measure sleep within the habitual environment of soccer players. Nine randomly selected male participants were monitored over 3 nights and comparisons were made between the WS and other established field measures of sleep (Wristwatch actigraphy, sleep diary and Firstbeat bodyguard heart rate system). The relationships between the WS and the other sleep devices, indicated strong to very strong correlations (r > 0.6) and no significant differences between a range of outputs; total sleep time (Actigraphy assumed sleep time [0.97] & Sleep Diary [0.87] p > 0.05), sleep onset latency (Actigraphy [0.69] p > 0.05) and number of awakenings (Sleep Diary [0.69], p > 0.05). There were also low bias and narrow limits of agreement (LOA) within the comparison of mean differences with the WS for assumed sleep time (2 ± 17 min 95% LOA: -30 to 34 min [Actigraphy]), sleep onset latency (7 ± 17 min, 95% LOA -28 to 40 min [Actigraphy]), and number of awakenings (0.05 ± 1, 95% LOA -3 to 3 [Sleep Diary]). These results suggested that the WS is a viable device for the detection of these selected sleep variables. Chapter 4 looked to provide a comparison of sleep measures between a sample of youth soccer players (N=8) and non-athletes (N=8). Both groups were monitored over a period of 6 days within the habitual setting using the WS. The findings showed the soccer player group attained greater amounts of sleep quantity in comparison to the non-athlete group (504 ± 22 vs. 433 ± 46 min [+71 min] total sleep time, ES: 2.0, Large, p < 0.01). This may have been as a result of a later time of final awakening (08:54 ± 00:14 vs. 07:34 ± 00:46 [+77 min], ES: 1.7, Large, p < 0.01). Such an observation suggested that the soccer players were afforded greater time in bed as a result of the imposed soccer schedule. The soccer players also displayed a statistically greater time spent in wake (13(13) vs. 3(5) min [+10 min], PS: 0.86 ES: 1.5, Large, p < 0.05) on average each night. This data suggested that the sleep of the youth soccer players might be less efficient (as a consequence of greater levels of disturbance), despite desirable quantities of sleep being attained than non-athlete controls. Chapter 5 provided a daily comparison of sleep measures conducted over a 14-day assessment period. It is apparent that youth soccer players attained more sleep quantity in the nights preceding the match day (M-2: 488 ± 53 min [ES: 0.91, Moderate; p = 0.06] & M-1: 486 ± 64 min [ES: 0.84, Moderate; p = 0.02] respectively) in comparison to the night of the day after the match day (M+1: 422 ± 61 min). Such a finding suggested that youth soccer players adopt behaviours that reduce their sleep quantity on the designated recovery day (M+1) by >60 min, which may impact the recovery processes associated to this day. Relationships between sleep parameters and training and match load indicated a 100 au rise in RPELOAD (RPE * Duration) increased the time spent in wake (42 s [90% CI: 0 to 84 s]; ES: 0.36, Small; p = 0.098). It was also observed that an increase of 1000 m total distance increased the time spent in wake (40 s [90% CI: 5 to 75 s]; ES: 0.33, small; p = 0.06) A 100 m rise in high-speed running distance increased the number of awakenings observed (0.14 [90% CI: 0.03 to 0.25]; ES: 0.28, p =0.04) and the time spent in wake on average each night (1.5 min [90% CI: 0.78 to 2.3 min]; ES: 0.57, Small; p = 0.04). A similar outcome was observed in Chapter 6 were a 100 m rise in average high-speed running distance across three different 14-day training periods during the youth soccer season showed a 5 min increase in the time spent in wake on average (ES: 0.88, moderate; p = 0.04). Such outcomes provided a potential link between increases in training intensity (i.e. high-speed running distance) and sleep disturbances within youth soccer players. Increases in high-speed running distance also related to an increase of 24 min (90% CI: 12 to 36 min) on average for total sleep time (ES: 1.3, large; p < 0.01). Similarly increased high intensity heart rate (>85% max HR) was shown to effect total sleep time +20 min (90% CI: 6 to 32 min; ES: 0.87, moderate; p = 0.035). This may suggest that increases in intensity also may impact the amount of sleep quantity within youth soccer players. At present the mechanism for this response largely remains unknown. Within Chapter 7, a practical sleep hygiene strategy (10 min showering at ~40 °C, 20 min before time of lights out) was investigated. A group of ten youth soccer players were evaluated under normal sleeping conditions (control) and a shower intervention period, each consisting of three days within a randomized cross over trial design. Sleep information was collected using the WS. In addition to skin temperature, which was evaluated using iButton skin thermistors. The iButtons were used to establish both distal and proximal skin temperatures. This data was also used to create the distal to proximal gradient (average of distal measures – average of proximal measures = DPG). The data demonstrated that the shower intervention elevated distal skin temperature by (+1.1 °C [95% CI: 0.1 to 2.1 °C]; ES: 0.44, Small; p = 0.04) on average during a 10-minute period prior to lights out in comparison to the control condition. This elevation was also present during the first 30 minutes following lights out (1.0 °C [95% CI: 0.4 to 1.6 °C]; ES: 0.65, Moderate; p < 0.01), which was also accompanied by an increased DPG between conditions (0.7 °C [95% CI: 0.3 to 1.2 °C]; ES: 0.45, Small; p < 0.01). Additionally it was observed that on average the sleep onset latency of the youth soccer players was lower in the shower intervention condition (-7min [95% CI: -13 to -2 min]; ES -0.55, Moderate; p = 0.007). However no other sleep variable was affected as a result of the intervention. These findings demonstrate that a warm shower performed before lights out may offer a practical strategy to alter the thermoregulatory properties of distal skin temperature, which may advance sleep onset latency within youth soccer players.
59

An evaluation of the physical demands of American football training in the NFL

Ward, P. A. January 2018 (has links)
American football is one of the most popular sports in the United States. However, unlike other football codes, little is known about its physical demands. Aside from a limited amount of research conducted on college players during training and matches, no research exists on players at the elite level, in the National Football League (NFL). Therefore, the primary aim of this thesis was to evaluate the physical demands of training in the NFL. This aim was achieved by establishing a systematic approach to training evaluation using three main phases of study: (1) Evaluation of monitoring strategies in American football; (2) Description of American football training demands with an emphasis on periodization; and, (3) Examination of the consequences of training with an emphasis on injury risk. The first study of this thesis (Chapter 3) showed that three commercially available inertial sensors were able to differentiate between fundamental American football actions (e.g., sprinting, change of direction, and collisions) during movement tasks in a controlled setting and may be useful for quantifying the physical demands of training. During training sessions, Session Rating of Perceived Exertion exhibited a variety of individual responses making sRPE challenging to use when exclusively evaluating the physical demands of training (Chapter 4). Therefore, more objective measures (e.g., GPS and inertial sensors) were evaluated during training (Chapter 5) and indicate that commonly used measures of distance and velocity may not adequately describe the physical demands for some position groups. As such, inertial sensors offer more flexibility to classify a broad range of activities within the sport. A number of inertial sensor metrics are available to the practitioner in commercially used systems. Chapter 6 utilized a principal components analysis to reduce eleven variables to 3 principal components, explaining 79% of the variance within the data. These findings suggest that a small number of variables (e.g., Player Load and IMA) may be adequate when describing the training demands of the sport. Given the reduction in measures to report, Chapter 7 used Player Load and IMA to describe the periodization strategies across a season and within the training week employed by the coaches of one NFL team. Training load was observed to decreases across the season with no clear periodization structure. Conversely, within the weekly micro-cycle, coaches appear to employ some pattern of periodization whereby training load is seen to systematically decrease as the game nears. The final phase of this thesis (Chapter 8) investigated the consequences of American football training by exploring the relationship between training load measures (Player Load, IMA, and Impacts) and non-contact soft tissue injury. Several logistic regression models were compared using Bayesian Information Criterion (BIC). The best model suggested that sessions with greater volume (PLTotal) and intensity (ImpactsHigh) were associated with non-contact soft tissue injury in American football players and may have implications for practitioners when designing training programs within the sport. Collectively, this thesis has the potential to not only offer practitioners within American football a way forward in terms of evaluating training demands but also may be influential to the broader scope of sports science given some of the novel statistical approaches taken to understanding training load monitoring.
60

Sensorimotor processes underpinning imitation learning of biological motion

Dutoy, C. A. January 2018 (has links)
The aim of the present thesis was to examine the way in which biological motion is coded and imitated during imitation learning by improving upon methodologies currently used in the literature to examine imitation of underlying movement kinematics. Across four experiments, imitation of the kinematic structures of biological and non-biological motion models was examined to investigate the processes involved in imitation learning. The purpose of the first experimental chapter, Chapter Two, was to examine the way in which biological motion kinematics were coded during imitation learning by establishing whether imitation of biological motion kinematics was a function of lower-level visuomotor processing or top-down attentional modulation. Results showed that not only were imitations of typical and atypical biological motion different, but both models were imitated as accurately during spatially incompatible trials as compatible. Accurate imitation of spatially incompatible atypical biological motion confirmed biological motion coding is a function of lower-level visuomotor processing. Following results from Chapter Two, Chapters Three, Four and Five assumed lower-level visuomotor processing of biological motion and were designed to further examine whether this lower-level visuomotor processing of biological motion was modulated by top-down attentional factors (e.g. end-state-targets, visual attention, social primes). The first of these top-down modulations was included in Chapter Three, which examined the influence of end-state-targets on biological motion coding during imitation learning. Although kinematics was not modulated by end-state-targets, movement time was less accurate when end-state-targets were present, which suggests that lower-level and top-down processes operate together during the processing of visual information during imitation learning. In addition to end-state target modulation, imitation data further confirmed the coding of atypical biological motion by demonstrating differences in imitation of two relatively similar atypical biological motion models (atypical17 and atypical26). The top-down attentional factor examined In Chapter Four was visual attention, which was measured by recording eye movements during observation of the model stimuli. Analysis of eye movements demonstrated that visual attention was directed towards the model throughout the entirety of the observation phase during trials where end-state-targets were both present and absent. As goal-directed eye movements were not made during observation of the models, results suggest that the kinematic data contained within each of the models was observed and consequently featured in the representation formed for motor execution. Chapters Two, Three and Four provide a fundamental understanding of how biological motion is coded during imitation learning by using robust protocol that improves upon the validity of those used in the current literature and specific modulations that discredit significant top-down modulatory explanations for biological motion coding. The way in which biological motion coding occurs in neurotypicals (no neurologically atypical patterns of thought or behaviour) is important when trying to understand where deficiencies in those with intellectual disabilities occur. The intellectual disability most closely associated with the current thesis is autism, where deficiencies in imitation are suggested to be linked to social components. Therefore, to establish a foundational understanding of how social context influences neurotypical imitation, Chapter Five examined the influence of social primes on the coding of biological motion. Results showed that social primes modulated the accuracy of imitation, where peak velocity was more like those of the models following observation of an anti-social prime. In addition, observation of both the pro- and anti-social primes was shown to reduce the variability of imitation relative to observing no social prime at all. These findings demonstrate that social primes are being coded and incorporated into the motor output such that both the accuracy and consistency of imitation of biological motion are modulated. Together, the results presented in the current thesis demonstrate imitation of novel, atypical biological motion is a function of complimentary lower-level and top-down processes that facilitate the coding of both underlying kinematics and environmental context.

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