Sports Sciences Commons^™

Relative Importance And Plasticity Of Anatomical And Neuromuscular Factors Affecting Joint Torque Production, Joanne C. Trezise

Theses: Doctorates and Masters

The present research aimed to determine (i) the relative influence anatomical and neuromuscular variables on maximal isometric, concentric and eccentric knee extensor torque (Study 1); (ii) whether the change in strength following a 10-week strength training program is associated with changes in specific anatomical and neuromuscular variables (Study 2a); (iii) whether anatomical and neuromuscular adaptations are dependent on their pre-training magnitudes; and (iv) whether it is possible to ‘predict’ an individual’s adaptation to strength training based on their anatomical and neuromuscular pre-training magnitudes (Study 2b).

The variables assessed throughout the studies include muscle cross-sectional area (CSA), fascicle length and angle …

Role Of Physical Exercise In Reducing Depression And Improving Mental Health In Cancer Survivors, Gregory Levin

Theses: Doctorates and Masters

Cancer survivors are more than twice as likely as the general population to suffer the debilitating effects of depression. This comorbid condition is associated with several negative consequences, such as reduction in compliance with cancer treatments, and hastened mortality. Recent research has examined the therapeutic effect of exercise on depression and reported excellent results of similar magnitude to those achieved with pharmacotherapy or psychological intervention. However, no research, to date, has examined the effectiveness of exercise on reducing depression in depressed cancer survivors. In order to address this important question this thesis reviewed previous literature in the area of cancer …

Neuromuscular Factors Affecting Stretch-Induced Torque Loss, Gabriel Siqueira Trajano

Theses: Doctorates and Masters

The mechanisms underpinning the immediate torque loss induced by acute, static muscle stretching are still not clear. The current research was designed to examine the neuromuscular factors influencing this torque loss. In Study 1, the contributions of central versus peripheral factors to the stretch-induced torque loss were investigated. Measures of central drive, including the EMG amplitude normalised to the muscle compound action potential amplitude (EMG:M), percent voluntary activation (%VA) and first volitional wave amplitude (V:M), and measures of peripheral function, including the twitch peak torque and 20:80 Hz tetanic torque ratio were made before, and immediately and 15 min after …

The Creation And Validation Of A Youth Fundamental Hitting Scale: The Assessment Of Youth Baseball And Softball Hitting Fundamentals And The Perceived Psychological Barriers To Hitting A Pitched Ball, Andrew Walsh

Theses: Doctorates and Masters

The primary purpose of the thesis was to create a hitting scale for youth players that assess the fundamentals of a baseball swing. Secondly, the purpose of this thesis was to determine the interactions between the changes in anxiety, perceived competence and fear variables have with actual hitting competence over a four week sport specific training program.

Acute Physiological Effects And Perceived Enjoyment Of A Single Bout Of Aerobic Interval And Continuous Moderate-Intensity Cycling In Overweight And Obese Individuals, Fujie Koh

Theses: Doctorates and Masters

Aerobic interval training, a form of high intensity interval training, is commonly prescribed to both the general and clinical populations. However, the acute physiological effects from a single bout of aerobic interval session are not fully understood. In training studies, these acute physiological effects may confound actual training adaptations when they occur following the final training session [1]. Furthermore, while recreationally active men perceived aerobic interval training to be more enjoyable than continuous moderate-intensity exercise [2], the preference of overweight and obese individuals has not been extensively researched. Since overweight and obese individuals tend to have lower exercise tolerance, it …

Understanding And Improving Pacing Strategies During Standard Distance Triathlons In Age Group Athletes, Sam Shi Xuan Wu

Theses: Doctorates and Masters

Pacing is an integral aspect of performance during all exercise, including multi-sport events such as triathlon. However, to date, the optimal pacing strategies to adopt over an entire triathlon, as well as during each specific discipline (i.e. swim, cycle and run), is not well understood. Therefore, the primary purpose of this thesis was to identify and understand current pacing strategies adopted by highly performing triathletes across different triathlon distances. This research aids in identifying pacing strategies that may improve overall performance during triathlon.

In the first study, the influence of sex and race distance on the age-related declines in the …

A Series Of Studies Examining The Development Of Sprint Speed And Momentum Of International Rugby Union Players, Matthew John Barr

Theses: Doctorates and Masters

Sprinting speed is a highly valued physical ability in rugby. There is little research examining sprinting biomechanics in rugby players and it is unclear the extent that sprinting speed and sprint momentum can even be improved in highly trained rugby players and how different speed and strength training methods might help improve it. This thesis consists of 6 studies that examine the sprinting biomechanics of elite rugby players, how strength and power training might improve sprinting speed and the potential for elite rugby players to make further improvement in their sprinting speed and sprint momentum.

Key biomechanical factors were that …

Comparison Of The Physical, Physiological And Perceptual Demands Of Small-Sided Games And Match Play In Professional Football Players, Stephen Hissey

Theses: Doctorates and Masters

The physical and technical requirements of a range of small-sided football (soccer) games (SSGs) have previously been examined in order to compare their requirements to competitive match play. SSGs are used to combine the technical, tactical and physical components of normal match play in training in order to make the training sessions specific to football. However, most previous research has focused on youth players and it is known that the playing patterns, and thus session outcomes, are different for elite players. Consequently, research examining elite players is required in order to improve our understanding of the use of SSGs in …

An Investigation Of Technique And Equipment Factors Associated With Clubhead Speed In Golf, Christopher Joyce

Theses: Doctorates and Masters

If golfers achieve long hitting distances whilst maintaining their accuracy they will gain a competitive advantage. To increase hitting distance, faster clubhead speed is required and this can potentially be achieved through a number of factors. Firstly, anthropometric factors such as height and physical factors such as trunk rotational power have been previously considered to be of importance. However, biomechanical factors such as; the X-factor (separation of the trunk-pelvis alignment when viewed in the transverse plane), have been a major focus of recent research. Further, the interaction of the golfer with the implement they hit with i.e. the golf club …

Mechanisms Affecting Post-Activation Potentiation Following Voluntary Isokinetic Knee Extension, Laurent B. Seitz

Theses: Doctorates and Masters

The present research was designed to: 1) determine whether the voluntary PAP effects commonly observed after conditioning activity (CA; i.e. muscular contraction prior to a ‘test’ contraction) are a consequence of acute neuromuscular alterations relating to the CA itself, or whether they simply reflect warm-up and/or familiarisation effects; 2) clarify the influence of the contraction velocity, duration and total work characteristics of the CA on voluntary PAP; 3) determine the factors allowing stronger individuals to express higher level of voluntary PAP; and 4) determine the peripheral and central mechanisms of voluntary PAP in human skeletal muscle. In Study 1, the …

Pain Assessment And Possible Mechanism Of Delayed Onset Muscle Soreness, Wing Yin Lau

Theses: Doctorates and Masters

Muscle pain is felt during exercise or daily activities for several days after performing unaccustomed exercise, which is referred to as delayed onset muscle soreness (DOMS). Many people experience DOMS, but its underlying mechanisms are not fully understood. One of the challenges in the investigation of DOMS is its subjective nature, which makes the assessment ambiguous, thus establishing a standardised protocol is necessary. The present thesis scrutinised muscle pain assessments (Study 1, Study 2), developed a new assessment of muscle pain focusing on muscle fascia (Study 3), and investigated why DOMS is reduced after the second than the first bout …

Neuromuscular Fatigue Following A Singles Badminton Match, Zengyuan Lin

Theses: Doctorates and Masters

A typical badminton singles match involves numerous intense and high impact movements. Lunges were accounted for approximately 15% of overall movements and were believed to presumably induce significant muscle damage following a match. However, no previous study has investigated changes in knee extensor muscle function after a badminton match.The present study investigated changes in knee extensor neuromuscular function and muscle soreness after a simulated 1-h badminton singles match in relation to the number of lunges performed in the match.

Ten state-level male badminton players were recruited (n=10), with each player played a total of eight simulated 1-h matches under the …

The Development And Evaluation Of A Testing Protocol To Assess Upper Body Pressing Strength Qualities In High Performance Athletes, Kieran Young

Theses: Doctorates and Masters

PURPOSE: The purpose of this study was to evaluate the reliability of an isometric force assessment (isometric bench press) across 4 standardised angles and an isoinertial force and velocity assessment (ballistic bench throw) utilising a relative load based on a percentage of one repetition maximum (1RM) in the bench press; and to evaluate whether the use of the dynamic strength deficit (DSD) ratio can guide training and detect changes induced by training over a 5 week period.

METHODS: Twenty four elite male athletes (age = 19.9 ± 2.7yrs; mass = 79.1 ± 13.0kg) performed the isometric bench press and a …

Exploring Predictors Of Sport Commitment In Coaches, Erin Bormann

Theses: Doctorates and Masters

The Sport Commitment Model (SCM) has been used to gain insight about the factors that influence people’s decision to continue participation in sport. Majority of the studies that are grounded in the SCM have been conducted with athletes. To date, few studies have examined sport commitment of coaches however, these did not assess two commitment dimensions per se (functional or “want to” and obligatory or “have to” commitment to sport), rather each has measured certain predictor variables and inferred commitment dimensions based on clustering of predictors [i.e. 13]. This study had one main purpose, to examine the SCM amongst coaches. …

Neuromuscular Fatigue And Biomechanical Alterations During High-Intensity, Constant-Load Cycling, Amanda Julie Overton

Theses: Doctorates and Masters

Neuromuscular fatigue is an inevitable process at play during prolonged exercise, and may be caused by multiple alterations within the central nervous system and peripheral musculature. As fatigue develops, the neuromuscular system must adapt to these changes by making compensatory movement pattern adjustments so as to use motor pathways that are less fatigued in an effort to maintain task performance; motor variability is thus increased. The primary purpose of the four studies contained within this doctoral thesis was to detail the progression of exercise-induced neuromuscular fatigue, and to improve our understanding of the muscle activation and joint kinematic alterations that …

Exercise As Medicine : Reversing Treatment Toxicities In Prostate Cancer Patients, Bradley A. Wall

Theses: Doctorates and Masters

A common treatment for prostate cancer, which is the most common form of cancer after skin cancer in Australian males, is androgen deprivation therapy (ADT). However, ADT is associated with an array of adverse effects including reduced bone and lean mass, loss of muscle strength, negative change in lipid profile, and increased risk of cardiovascular disease (CVD) as well as diabetes, all of which can compromise physical function and quality of life. Physical exercise has been suggested as a key lifestyle intervention for this group of cancer patients as it has enormous potential to limit and even reverse the effects …

Effects Of Pulsed Electromagnetic Field Therapy On Symptoms Associated With Eccentric Exercise-Induced Muscle Damage, Henry Banyard

Theses: Doctorates and Masters

Unaccustomed exercise consisting of eccentric contractions induces muscle damage that is characterised by muscle weakness, soreness, swelling and increased muscle stiffness. These symptoms affect daily activities and athletic performance; therefore, interventions to attenuate the symptoms and enhance recovery from muscle damage are necessary. Pulsed electromagnetic field therapy (PEMFT) is anecdotally reported to increase muscle blood flow and oxygenation to enhance tissue healing. One previous study showed that PEMFT was effective for alleviating muscle soreness and losses in range of motion after exercise. However, studies investigating the effect of PEMFT on recovery of muscle strength following eccentric exercise are lacking. The …

The Influence Of External Loading And Speed Of Movement On Muscle-Tendon Unit Behaviour And Its Implications For Training, Jacob Earp

Theses: Doctorates and Masters

In this thesis great emphasis has been placed on vastus lateralis (VL) muscle-tendon unit (MTU) structure, behaviour/movement and adaptation. Of particular interest was how external loading and movement speed influence these variables. In the first study (Chapter 3) we developed a new methodology by which electromyography (EMG) could be normalised during large range of motion knee extensions. This methodology was then used as part of a larger study, which investigated how external loading influenced the interaction of muscle and tendon (MTU behaviour) during stretch shortening cycle isoinertial knee extensions, and how muscle activity and intrinsic tendon force (Ft) influenced MTU …

Approach-Iron Play In High Performance Golf: From Testing To Tournament Play, Samuel John Robertson

Theses: Doctorates and Masters

The capability of a golfer to record a low score depends upon well-developed abilities in each of the recognised on-course skill components (driving the ball off the tee, hitting approach-iron shots, hitting short-iron shots and putting). Despite approach-iron play being considered perhaps the most important and definitely the most practiced skill in the game, the ability to quantify the golfer’s ability to hit approach-iron shots in a controlled, off-course environment (eg. training) cannot yet be undertaken due to the lack of appropriate assessments. Such tools have considerable potential for use in both the field and in research for implementation in …

Muscle Damage And Metabolic Profiles Of Eccentric Cycling, Luis Penailillo

Theses: Doctorates and Masters

Eccentric cycling, in which the knee extensor muscles perform eccentric contractions while trying to brake the backward rotational movements of the cranks of a cycle ergometer, has been shown to effectively increase muscle function and volume with a low metabolic cost. However, acute responses to repeated eccentric cycling bouts have not been well documented. Thus, the primary purposes of this PhD project were to investigate muscle damage and metabolic profiles of eccentric cycling in comparison to concentric cycling (Studies 1-3), and muscle-tendon behaviour (Study 4) during eccentric cycling in relation to muscle damage.

Study 1 compared muscle damage and metabolic …

Monitoring Neuromuscular Fatigue In High Performance Athletes, Kristie-Lee Taylor

Theses: Doctorates and Masters

With improving professionalism of sports around the world, the volume and frequency of training required for competitive performances at the elite level has increased concurrently. With this amplification in training load comes an increased need to closely monitor the associated fatigue responses, since maximising the adaptive response to training is also reliant on avoiding the negative consequences of excessive fatigue. The rationale for the experimental chapters in this thesis was established after considering survey responses regarding current best practice for monitoring fatigue in high performance sporting environments (Chapter 3). On the basis of the results, vertical jump assessments were selected …

Assessment And Training Of Muscular Force And Power Qualities Of The Lower Limb Using Traditional And Cluster Loading, Keir Hansen

Theses: Doctorates and Masters

It is widely accepted that lower body muscular force and power capabilities are of significant importance to many athletic tasks. Thus the assessment and training of these qualities are a key focus in both sports science and strength and conditioning practice. The purpose of this thesis was firstly to investigate previously discussed but poorly researched methods of assessing force and power characteristics of the lower limb particularly focusing on the analysis of the force-time and power-time curves during the rebound jump squat, and secondly, to investigate the effectiveness of cluster loading, an alternative resistance training paradigm, in training for lower …

A Kinanthropometric Analysis Of Accurate And Inaccurate Kickers: Implications For Kicking Accuracy In Australian Football, Nicolas H. Hart

Theses: Doctorates and Masters

A paucity of research exists investigating the potential relationship between the technical and temporal strategy of accurate and inaccurate kickers in response to physical parameters modifiable by athletic conditioning. While recent studies have produced improvements in performance when kicking for distance following structured resistance training interventions, no studies have examined the influence of such interventions on the enhancement of kicking accuracy. It was therefore the purpose of this thesis to extend scientific understanding of those mechanisms which might underpin accurate kicking performances through examining kinanthropometric, strength and muscularity profiles of accurate and inaccurate kickers in Australian Football using a series …

Practical Precooling Strategies And Cycling Time Trial Performance, Megan L. Ross

Theses: Doctorates and Masters

Whole-body precooling can improve endurance exercise performance, especially in the heat; however there are logistical considerations that restrict the use of various precooling strategies prior to actual competition. Precooling is proposed to collectively reduce deep skin and body temperature and in effect, increase the heat storage capacity of an athlete, thereby allowing a greater amount of work to be completed prior to attainment of a critical core temperature. While there is a sound theoretical basis for implementing precooling to improve cycling time trial performance in the heat, the practicalities of employing effective precooling strategies in the field warrant further investigation. …

Thermoregulatory And Exercise Performance : Responses To Cooling With Ice Slurry Ingestion, Rodney Siegel

Theses: Doctorates and Masters

The rise in body core, skin and muscle temperatures associated with exercise
in hot environments (~30°C and above) is known to impair performance over a
variety of exercise modes and durations. Precooling has become a popular strategy to
combat this impairment, as evidence has shown it to be an effective method for
lowering pre-exercise core temperature, increasing heat storage capacity and
improving exercise performance in the heat. To date, the majority of precooling
manoeuvres are achieved via external means, such as cold water immersion and the
application of cooling garments; methods which have been criticised for their lack of
practicality …

Effect Of Transcranial Direct Current Stimulation (Tdcs) On Maximal Voluntary Isometric Strength And Endurance Of The Elbow Flexors, Benjamin Kan

Theses: Doctorates and Masters

The present study investigated the effects of transcranial direct current stimulation (tDCS) on maximal voluntary contraction strength (MVC) and the time to failure (TTF) of an isometric muscle endurance test of the elbow flexors. Prior to the main study, the test-retest reliability of MVC and TTF measures was investigated using 10 men (33.2 ± 9.4 y) for the measurements separated by 60 min (within-day) and one week (between-day). Coefficient of variation (CV), Intraclass correlation (ICC, R), a paired t-test and the Bland-Altman plots revealed that TTF at 30% MVC task was reliable, and was able to detect a possible effect …

Feedback Control For Exergames, Jeff Sinclair

Theses: Doctorates and Masters

The concept of merging exercise equipment with video games, known as exergaming, has the potential to be one of the main tools used in addressing the current rising obesity epidemic. Existing research shows that exergaming can help improve fitness and additionally motivate people to become more active. The two key elements of attractiveness - how much people want to play or use the exergaming system; and effectiveness – how effective the exergaming system is in actually increasing or maintaining physical fitness, need to be maximised to obtain the best outcomes from an exergaming system; we put this forward as the …

The Influence Of Set-Repetition Configuration In Eccentric Exercise On Muscle Damage And Repeated Bout Effect, Roy Y.H. Chan

Theses: Doctorates and Masters

It is well known that maximal eccentric exercise induces muscle damage, especially when it is performed for the first time. However, muscle damage is attenuated in subsequent bouts of the same or similar exercise, which is known as the repeated bout effect. One of the factors affecting the magnitude of muscle damage and the repeated bout effect is the number of eccentric contractions; however, it is unknown if different set-repetition configurations with the same number of eccentric contractions would result in different magnitudes of muscle damage and adaptation. This study investigated changes in muscle strength, range of motion (ROM), muscle …

Comparison Of Acute Physiological Effects Between Alternating Current And Pulsed Current Electrical Muscle Stimulation, Abdulaziz A. Aldayel

Theses: Doctorates and Masters

Electrical muscle stimulation (EMS) is widely used in rehabilitation and sport training, and alternating current and pulsed current EMS are commonly used. However, no systematic comparison between alternating and pulsed current EMS has been made in the previous studies. The main aim of this research was to compare acute physiological responses between the alternating and pulsed current EMS. The secondary purpose of the research was to investigate further muscle damage induced by EMS-evoked isometric contractions. Three experimental studies were conducted in the thesis project together with literature review about EMS.

Low Back Pain In Schoolgirl Rowers: Prevalence, Bio-Psycho-Social Factors And Prevention, Debra Perich

Theses: Doctorates and Masters

Rowing is one of the largest participant sports on the Independent Girls‟ Schools Sporting Association (IGSSA) in Western Australia with approximately 400 participants competing every year. Rowing is an extra-curricular sport offered to girls 14 years of age and above, with these girls competing and training in both sweep and scull boats. Whilst the benefits of regular physical activity and exercise are well known, musculoskeletal problems have been documented in rowing. In particular, clinical evidence and previous research suggests that low back pain (LBP) is common in rowers. Adolescents who suffer from LBP are at an increased risk of recurrent …