1,720,988 research outputs found
Can you feel the pressure? Examining the effects of anxiety in elite netball shooters
Full text linkNetball is an increasingly popular sport for women in New Zealand, with the national league competition being fully professional. One important skill within netball is goal shooting, as the goal volume and accuracy ultimately decides the outcome of the game. Therefore, it is critical that shooters are able to perform this task well under pressure. The first part of this thesis reviews the literature on the effects of anxiety on sport performance. The second part of this thesis includes two studies. The first study, Study A (Chapter 2), was an observational, retrospective analysis of performance of 15 shooters in the top New Zealand competition at different score-lines and time points throughout netball games. The analysis showed that when one and two goals ahead, as well as other specific time points such as first shot of the quarter, the shooters shot significantly worse than the individual mean accuracy, but when three or four goals ahead the opposite effect occurred, a performance decrease. The fluctuation in performance demonstrated the possible influence of anxiety and individual differences on performance under pressure, along with the need to examine performance under pressure in a controlled setting in elite netball shooters. The second study, Study B (Chapter 3), was an experimental study designed to investigate the anxiety-performance relationship in elite netball athletes. Eleven elite netball shooters performed 100 shots at goal under four conditions: high-pressure defender present, high-pressure defender absent, low-pressure defender present, and low-pressure defender absent. Increased perceived anxiety, heart rate and task completion time occurred in the high-pressure conditions; however trait anxiety, concentration disruption in particular, predicted performance under low-pressure but not high-pressure conditions. In conclusion, the outcomes of these studies demonstrate that performance fluctuation occurs under pressure and that there may be individual differences in performance under pressure. The need for greater investigation of anxiety induced by high-pressure in elite professional netballers is apparent
The effects of flotation-restricted environmental stimulation therapy on post-exercise recovery in trained athletes
Full text linkFlotation-restricted environmental stimulation therapy (FLOAT) is a method of sensory deprivation and a relaxation technique that has proven to benefit individuals suffering from various health disorders. The objective of this thesis was to first review the literature surrounding FLOAT and to assess the proposed benefits to physiology, psychology, creativity and learning, sleep, psychomotor performance, mental health and physical performance. Through evaluating the literature in combination with the proposed theoretical mechanisms of FLOAT, gaps in the existing research were identified, specifically, the effects of FLOAT on post-exercise recovery in trained athletes. Following the review of literature, this thesis included an original research study to investigate the effects of FLOAT on post-exercise recovery, evaluating hormonal responses, sleep, and next day physical performance measures in athletes. Nineteen trained, male team-sport athletes completed two trials separated by seven days; FLOAT, which included 60 minutes of FLOAT recovery following exercise, and CON, which included 60 minutes of passive recovery following exercise. The exercise consisted of the basketball exercise simulation test (BEST), an exercise consisting of various movements (walking, jogging, sprinting, jumping, shuffling). Performance and pressure-to-pain algometer measures were taken pre and post exercise and the following morning. Performance measures included an isometric mid-thigh pull, a countermovement jump, a 15 m sprint, and a repeated-sprint test. Perceived measures of muscle soreness and physical fatigue were recorded up to 24 h post testing. Salivary cortisol samples were collected pre and post exercise and post recovery. Sleep was monitored via wrist-actigraphy. The results showed that compared to CON, FLOAT significantly (p < 0.05) enhanced countermovement jump, 10 m sprint, and 15 m sprint performance, with small to moderate effects for all performance measures excluding the countermovement jump (unclear). The results also showed significantly higher pressure-to-pain thresholds across all muscle sites, and lower muscle soreness and physical fatigue following FLOAT. All sleep measures resulted in small to moderate effects, with a significantly greater perceived sleep quality for the FLOAT trial compared to CON. In conclusion, FLOAT may prove to be a beneficial post-exercise recovery technique that positively influences sleep, physical fatigue, muscle soreness and performance
Cognitive control processes during balance and locomotion : walking an attentional tightrope
No full textThe Theory of Reinvestment proposes that relatively automated motor performance can be disrupted by conscious step-by-step movement processing using previously acquired verbal knowledge. Movement specific reinvestment has been widely examined in ontogenetic motor skills (i.e., skills that extend fundamental movements for specialized purposes and must be deliberately learned), for which verbal knowledge is more readily available. Therefore, in five studies this thesis examined the role of movement specific reinvestment in young and older adults during phylogenetic motor skills (i.e., fundamental movements), balance and walking. It was found that movement specific reinvestment played a role in balance performance by young adults but not older adults (Chapters 2, 3, and 4). Specifically, young adults with a high propensity for reinvestment showed a more constrained, less complex, mode of balancing than young adults with a low propensity for reinvestment. However, verbally describing (overshadowing) balancing affected the performance of young adults with a low, but not a high, propensity for movement specific reinvestment. It was argued, that people with a high propensity for reinvestment, contrary to people with a low propensity, were accustomed to verbal processing and therefore were not affected by verbalization. It was further argued that movement specific reinvestment may not have played a role in balance performance by older adults because older adults did not possess, or could not access, verbal knowledge about their balancing. On the other hand, for older adults, an association was found between movement specific reinvestment, attention focus and visuo-motor control during walking in a demanding environment that required accurate stepping and navigation of obstacles (Chapters 5 and 6). Specifically, older adults with a high propensity for movement specific reinvestment compared to a low propensity for movement specific reinvestment showed greater awareness of their body movements and decreased awareness of the external environment during walking. Furthermore, they also displayed longer stance and double support times when approaching a stepping target and, subsequently, increased stepping error. It was argued that because of the tendency to engage in verbal processing, older adults with a high propensity for movement specific reinvestment needed more time to “plan” their stepping movements - this inefficient information processing lead to worse stepping accuracy. The findings of this thesis inform the Theory of Reinvestment and contribute to current understanding of the role of consciousness in phylogenetic motor skills.published_or_final_versionPublic HealthDoctoralDoctor of Philosoph
Associations between fundamental movement skills, gymnastics and movement specific reinvestment
Full text linkThe propensity for conscious monitoring and control of movement (i.e. movement specific reinvestment) influences the acquisition of movement skills. Fundamental movement skills (FMS) are basic motor skills that children must learn and accomplish as they are a key component for participation in sport and physical activity. Recreational gymnastic programmes are saturated with activities associated with the development of FMS, so this study aimed to examine the relationship between conscious control of movements, as defined by the theory of reinvestment (Masters, 1992; Masters & Maxwell, 2008; Masters, Polman, & Hammond, 1993), fundamental movement skills and gymnastic skills in children. The purpose of this study is to understand the role of movement specific reinvestment (MSR) and gymnastics experience in developing FMS and gymnastic- specific skills in children.
Two hundred and two novice child gymnasts (Mean age = 8.02 ± 2.35 years; range = 5-15 years) were asked to complete a modified version of the Movement Specific Reinvestment Scale for Children (MSRS-CC) (Ling, Maxwell, Masters, McManus, & Polman, 2016; Masters, Eves, & Maxwell, 2005; Masters & Maxwell, 2008) in week 1 and week 9 of a gymnastic course to measure their propensity to consciously monitor and control their movements. Children repeated the modified MSRS-CC again in week 9 to investigate whether the propensity for movement specific reinvestment changed. The children were assessed on two basic gymnastic skills in week 1 and week 9 to investigate whether the propensity for movement specific reinvestment accounts for improvement of gymnastic skill acquisition. Children were also asked to perform four FMS from the two subcategories of object control and locomotor skills in week 1 of the gymnastic course. When registering to participate, parents indicated the level of their child’s previous gymnastic experience by answering questions to investigate if a child’s gymnastic experience and propensity for movement specific reinvestment is associated with developmental level of FMS.
The results showed that out of the four measured FMS (horizontal jump, slide, stationary dribble, and underhand throw) only horizontal jump was significantly correlated with gymnastics experience, with more experience associated with better performance. The results further showed that lower scores on the Movement Specific Reinvestment Scale were associated with improvements in the gymnastic skill of the forward roll. When examining the individual contribution of CMP and MS-C to the development of the forward roll, only CMP was found to significantly account for the improvements, with higher scores on CMP associated with less improvement. Results also indicated that both CMP and MS-C increased significantly from week 1 to week 9, suggesting that post-training children tended to consciously engage in movement processing more than pre-training. Training instruction appears to impact reinvestment propensity. To accelerate children’s development of FMS, children need to reduce reinvestment, and this could be achieved with implicit instructional methods that avoid explicit directions to monitor movement and appearance
Reduced global processing bias in people with a history of mild traumatic brain injury: Grass everywhere and not a field in sight
No full textMild traumatic brain injury (mTBI) is increasingly recognized as a disconnection syndrome, due to the prevalence of disrupted long-range connections. Long-range connections refer to neural pathways that span across brain regions, allowing communication and synchronization between different brain areas. Disruption of these connections is associated with the inability to efficiently integrate local information (i.e., multiple visual attributes) into the percept of a single global shape. The aim of this thesis was to investigate whether people with a history of mTBI exhibit a reduced ability to integrate local information into meaningful context.
Chapter 2 investigated whether visual integration was impaired in people with a history of mTBI, using visual illusions. Susceptibility to visual illusions demonstrates effective integration of visual information to provide a global picture, with surrounding elements automatically integrated into the perception of local elements. Results from Chapter 2 revealed that people with a history of mTBI exhibited decreased susceptibility to visual illusions, suggesting diminished automatic integration of visual information in a global manner; rather, these individuals appeared to prioritize analysis of local details within a visual stimulus. To further investigate this assumption, we employed the Navon task in Chapter 3 to assess whether people with a history of mTBI demonstrated a tendency to prioritize the processing of local details over global information when presented with multiple objects. This task was chosen as it provides a reliable measure of the extent to which individuals engage in global or local processing. The results revealed that people with a recent history of mTBI (within 12 months) had a reduced bias towards processing global elements of a figure (i.e., attending to the overall configuration of the object), indicating a reduced automatic tendency to process visual information as a coherent global percept. In contrast, individuals who sustained their most recent mTBI more than one year earlier displayed the same global processing bias as control participants (i.e., they attended to the overall structure of the visual stimulus first).
Following this observation, it was speculated that people with a history of mTBI may also apply a de-automatized processing style to their movements. It has been argued that individuals with a high propensity to consciously process their movements are more likely to display de-automaticity (inefficient or disrupted movement); therefore, in Chapter 4 we assessed the propensity of people with a history of mTBI to consciously monitor and control their movements, using the Movement Specific Reinvestment Scale (MSRS). The results showed that people with a history of mTBI had a higher propensity for MSRS than controls. In addition, we found that time since most recent mTBI was negatively associated with the conscious motor processing subscale of the MSRS.
Chapter 5 builds upon the findings presented in Chapters 2 and 3, delving into the potential implications for real-world behaviours like visual anticipation. Specifically, this chapter investigated the impact of mTBI on individuals' ability to anticipate both deceptive and non-deceptive movements. The results demonstrate that people with a history of mTBI display significantly better anticipation of both deceptive and non-deceptive movements compared to control. Additionally, it was observed that people with a history of mTBI took longer to respond compared to controls.
The findings of this thesis suggest that there is an increased tendency to deconstruct visual and movement information following mTBI, highlighting a need for further research to better understand the effects of mTBI on information processing and to develop effective diagnostic and treatment strategies
Disrupting working memory to reduce verbal-analytical engagement in motor performance: Squeezing in a tiresome new approach to implicit motor learning!
Full text linkImplicit motor learning paradigms aim to minimise verbal-analytical engagement during motor performance. Some do this by suppressing working memory activity during practice. This reduces the ability of the learner to use, manipulate and store task-related information via mental processes, such as hypothesis testing. Implicit motor learning paradigms that suppress working memory indirectly are not always effective, because individual differences, such as motivation, can override their efficiency. The aim of this thesis was to investigate whether two more direct methods, cognitive fatigue and hand contractions, are viable tools with which to suppress working memory activity during motor practice, and whether they cause reduced verbal-analytical engagement in motor performance.
Chapter 2 investigated whether a computer-based cognitive fatigue task suppressed working memory activity during a golf putting task. Behavioural measures of verbal-analytical engagement were employed to test whether the cognitive fatigue task reduced hypothesis testing during the subsequent golf putting task. Results revealed that the computer-based cognitive fatigue task promoted cognitive fatigue, but was not sufficient to cause reduced hypothesis testing compared to a non-fatigue group.
In Chapter 3, a cognitive fatigue task with greater emphasis on motor control was therefore designed. It was first established whether the task caused cognitive fatigue and if working memory functions were disrupted. Subsequently, it was established whether the cognitive fatigue task reduced hypothesis testing during performance of a novel shuffleboard task, using behavioural measures, including self-report and assessment of technique changes. Additionally, verbal-analytical engagement in motor planning was gauged, using electroencephalography (EEG) to assess alpha power over the left temporal verbal-analytical (T7) site plus connectivity between the T7 and Fz (motor planning mid-frontal) sites. The results revealed that the motor-specific cognitive fatigue manipulation caused increased, rather than decreased, verbal-analytical engagement in motor performance, compared to a no fatigue control condition.
Chapter 4 examined whether hand contraction protocols influenced cognitive processes during motor performance, by using EEG to gauge verbal-analytical engagement during motor planning (i.e., T7-Fz connectivity) following a left-hand, right-hand or no hand-contraction protocol. The findings revealed that left-hand contractions, which are thought to activate the less verbal right hemisphere and deactivate the more verbal left hemisphere, caused reduced verbal-analytical engagement in motor planning, compared to the other protocols. Furthermore, right-hand contractions caused higher levels of verbal-analytical engagement in motor planning. Consequently, Chapter 5 investigated whether left-hand contractions promoted implicit motor learning. Participants practiced a motor task following regular bouts of left-hand contractions, right-hand contractions or no hand-contractions. Behavioral measures were used to gauge the extent to which verbal-analytical engagement was curtailed or encouraged. The results revealed no evidence that left-hand contractions promoted implicit motor learning, and both left-hand and right-hand contractions caused worse performance than no hand-contractions during a post-practice test phase.
Working memory performance was disrupted by both the cognitive fatigue and hand contraction protocols; however, predicted decrements in verbal-analytical engagement did not occur, and implicit motor learning was not promoted. The findings of this thesis reveal the complexity of the interrelationships between working memory, verbal-analytical processes and brain activity during motor learning. Future directions for research are considered
Testing the efficacy of motor analogies for landing safely from falls
Full text linkFall-related injuries are a major concern in countries with an aging population. One approach for reducing the likelihood of fall injuries is to teach older adults how to land safely. However, different safe landing techniques are required for different types of fall and direction of fall. Additionally, after a fall is initiated there is insufficient time to choose and use an appropriate safe-landing technique—particularly for older adults, who frequently display age-related cognitive deficiencies. Literature suggests that motor analogies are easy to retrieve from memory, can rapidly deploy attention during movement, and may even speed up the motor learning process. This thesis explores whether motor analogies can be utilized as a rule-of-thumb to promote safer landing (i.e., reduced risk of injury). Two laboratory experiments were conducted to examine the effect of motor analogies on biomechanical factors associated with landing by young adults (Chapters 2 and 4). A series of three online experiments examined whether motor analogies invoke mental representations associated with characteristics of safe landing (Chapter 3). Finally, a clinically-registered randomised controlled protocol was designed to investigate motor analogies in older adults (Chapter 5) (due to Covid-19 restrictions, the trial has not yet been completed). The findings suggest that an appropriate motor analogy can invoke mental representations associated with safe landing, and that participants instructed to use a motor analogy land in ways that are likely to result in less severity of injury, regardless of the direction in which they fall. The research provides preliminary evidence for the potential of motor analogies to reduce fall-related injuries, paving the way for future clinical studies
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Factors that influence motor performance: Colour, inhibition and conscious processing
Full text linkThis thesis investigates potential psychological mechanisms that influence motor performance in sport, including colour, inhibition function, and propensity for conscious control of movement. A question was raised about whether individuals with poor inhibition function would be more likely to have a high propensity for conscious control (i.e., reinvestment) because they are less able to inhibit conscious control. However, Experiment 1 (Chapter 2) and Experiment 2 (Chapter 3) revealed a positive association between inhibition function (indexed by the Go/NoGo task) and propensity for conscious control of movement (assessed by the Movement Specific Reinvestment Scale, MSRS).
Experiment 3 (Chapter 4) examined the effect of colour on inhibition function during a basketball-specific Go/NoGo task. Worse inhibition performance was evident when participants viewed an opponent in a green uniform compared to a red and a grey uniform, possibly because green conveys the meaning to ‘go’ (e.g., at traffic lights). Archival data of professional netball games was analysed to examine whether teams in green uniforms made more intercepts because green lowers an opponent’s ability to inhibit an ill-chosen pass. Findings revealed higher mean intercepts for teams wearing green uniforms than for teams wearing red and other-coloured uniforms.
Experiment 4 (Chapter 5) examined whether the effect of uniform colour may be due to differences in an opponent’s perception of size. A side-by-side comparison task revealed that goalkeepers in a red and a blue uniform were perceived as larger than goalkeepers in a green uniform, possibly because red and blue colours convey the meaning of dominance and threat in a football context (e.g., the most successful teams, like Manchester United and Chelsea, wear red and blue colours). Experiment 5 (Chapter 6) examined whether viewing a red and a blue spectator background would elicit avoidance motivation during football penalty-kicks, because they conveyed the meaning of dominance and threat. Professional football players displayed avoidance motivation (i.e., choosing the easier option/ kicking towards the larger side of the goal) when viewing a red and a blue spectator background compared to other-coloured backgrounds. Based on Experiments 4 and 5, it was argued that viewing a red and a blue spectator background elicited avoidance motivation because red and blue convey the meaning of dominance and threat in football.
In Experiment 6 (Chapter 7), retrospective analysis of professional football games was conducted to examine whether avoidance motivation would also be evident when facing a hostile crowd (a threatening stimulus). Consistently, penalty-kickers chose the easier option/ kicked to the larger side of the goal (i.e., avoidance motivation) more often when facing a hostile crowd rather than a supportive crowd. It was suggested that viewing a threatening stimulus (1) increases arousal levels, which exacerbates the negative emotions that are experienced by kickers during penalty-kicks in real-life or (2) viewing a threatening stimulus aids visual discrimination of available space, allowing kickers to identify and kick towards the larger side more often.
The findings of this thesis revealed a positive association between inhibition function and movement specific reinvestment propensity, which suggests that ability to inhibit inappropriate motor responses may be a function of inter-personal differences in the propensity for conscious control of movements. Support was found for the effect of colour in sporting contexts. Overall, the findings suggest that the colour effect only occurs if the colour-meaning association reaches an adequate salience threshold within a specific context. In addition, it was argued that while context influences emotional valence (positive, negative emotions), colour influences arousal, which exacerbates the level of negative emotion. An attempt is made to integrate the findings from the thesis with previous evidence to begin development of a theoretical framework for the effects of colour on human performance
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