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Within team sports, coaches aim to improve physical preparation by optimising the training process specific to competition. Unfortunately, at the elite level of wheelchair rugby (WCR) evidence-based information to guide this process is currently lacking. The present thesis investigates measures of external load during elite competition and explores whether this can be translated to inform current training practices. The first study established the suitability of a radio frequency-based, indoor tracking system (ITS) for the collection of movements specific to WCR. Minimal relative distance errors (< 0.2%) were seen across different sampling frequencies. Peak speed displayed the greatest relative error in 4 Hz tags (2%), with significantly lower errors observed in higher frequency tags (< 1%). The ITS was therefore deemed an acceptable tool for quantifying external load specific to WCR using a sampling frequency of 8 or 16 Hz. The external demands of elite competition were determined in Chapters 4 and 5. Notable differences in the volume of activity were displayed across the International Wheelchair Rugby Federation (IWRF) classification groups. However, the specific positional requirements of low-point (LP) and high-point players (HP) appeared to influence the intensity of external load (Chapter 4). Chapter 5 extended this work and established that peak speed and the ability to perform at high-intensities were best associated with successful mobility performance in WCR, as defined by team rank. This was further shown to be roledependent, whereby high-ranked HP players achieved greater peak speeds and performed more high-intensity activities (HIA) than respective lower-ranked players. Comparisons between the current external demands of training were then compared to that of competition (Chapter 6). Conditioning drills were shown to exceed the demands of competition, irrespective of classification. Notable differences in skill-based and game related drills were displayed across player classifications, whereby both were shown to be roledependent. Although game-simulation drills provided the best representation of competition, the duration appeared important since this factor influenced the results (Chapter 6). When the format of these drills were further modified (Chapter 7), drills containing fewer players increased the volume and intensity of training, specifically in HP. Whilst a 30-second shotclock elicited no changes in external load, differences were revealed when the shot-clock was further reduced to 15-s. Coaches can therefore modify the external training response by making subtle changes to the format of game-simulation drills. This thesis revealed that functional classification and positional-role are key factors during competition, and training should therefore be structured with this in mind. Conditioning drills can be used to elicit a progressive overload in the external responses, whilst game-simulation drills can provide the best representation of competition. Given the importance of gamesimulation drills, the combination of different formats throughout training sessions are critical in order to maximise the preparation of elite WCR players.

Although dynamic performance of a compliant mechanism is critical for many applications, majority of the research reported in the literature to date is limited to kinetostatic performance. The objective of this research is to develop a systematic method for dimensional synthesis of compliant systems for dynamic applications. The goal is to exploit the distributed compliance in an electromechanical system by effectively managing the stored elastic energy and inertial energy to minimize peak input power and average input power. For a given loading condition, the methodology developed in this research captures various elements that affect the system performance including the converter, actuator, and compliant transmission. A numerical method is used to handle the outer-loop optimization in searching for the optimal designs of a compliant mechanism. For each design of the compliant mechanism, optimal designs of the converter and the actuator are determined analytically in the inner-loop optimization. The method was extended to investigate optimal operating frequency and frequency robustness. The scope of this work is limited to plane-frame mechanisms, linear steady-state responses, single-input-single-output systems, and the use of finite difference for numerical optimization. To reduce peak input power, the study showed that either a statically-balancing principle or a dynamically-balancing principle can be employed, depending on the nature of the output load. Various modes of optimal designs were identified and it was found that designs for minimum overall size and minimum power consumption may not be the same, nor do they have to be at a resonance condition. This results in a tradeoff between overall size and power consumption. Finally, the methodology was demonstrated with two detailed design case studies: the design of a micro-pump and the design of a flapping mechanism. The primary contributions of this work include an approach to exploit elasticity in dynamic systems with different modes of optimal designs and a framework for dimensional synthesis of compliant systems for dynamic applications. The methodology developed in this research for modeling and optimization of power converter, input actuator, compliant mechanism, and external load can be extended to topology synthesis, large-displacement compliant mechanisms, three dimensional mechanisms, or multipleinput-multiple-output systems.