The Cortisol Awakening Response and Resilience in Elite Swimmers.

The sports environment is stress-eliciting in that it encapsulates perceived uncontrollability, unpredictability and requires ego-involvement. The HPA axis has been shown (indicated by cortisol release) to respond to anticipated sports competition up to a week prior to the event. Research also alludes to the importance of individual differences, such as optimism and trait perfectionism, in moderating the impact of cortisol upon performance. In total, 41 (male n=27) national (n=38) and international (n=3) swimmers were recruited from northeast England and Australia. Swimmers completed a measure of resilience and also provided buccal saliva swabs, from which total cortisol release prior to and during the event was calculated. Findings revealed that resilience significantly predicted performance and the influence of AUC (cortisol release) upon performance was moderated by resilience. These findings suggest that resilience can influence athletic performance either directly or indirectly, through appraisal (i. e., interpretation of the stressor to be facilitative and non-threatening).

Longitudinal changes in transtibial amputee gait characteristics when negotiating a change in surface height during continuous gait.

BACKGROUND: Negotiating a raised surface during continuous gait is an important activity of daily living and is a potentially hazardous task with regards to trips, falls and fall-related injury. However, it is not known how recent transtibial amputees adapt to performing stepping gait tasks in the 6-month period following discharge from rehabilitation. METHODS: Recent transtibial amputees performed continuous gait trials, stepping onto and from a raised surface walkway representing the height of a street kerb, whilst kinematic and kinetic data were recorded at one, three and six months post-discharge from rehabilitation. FINDINGS: Walking speed increased when stepping down (p=0.04) and was invariant across the study period when stepping up. At one month post-discharge, participants displayed an affected lead limb preference (90.8%) when stepping down and an intact lead limb preference (70.0%) when stepping up, although these lead limb preferences diminished over time. Participants spent more time in stance on the intact limb compared to the affected limb in both stepping down (trail limb) (p=0.01) and stepping up (lead and trail limbs) (p=0.05). Participants displayed significantly greater joint mobility and power bursts in the intact trail limb when stepping down and in the intact lead limb when stepping up. INTERPRETATION: Transtibial amputees prefer to exploit intact limb function to a greater extent, although over time, the means by which this occurs changes which affects the initial lead limb preferences. The results from the current study enable future evidence-based therapeutic and prosthetic interventions to be designed that improve transtibial amputee stepping gait.

Exploring individual differences in children's mathematical skills: a correlational and dimensional approach.

Individual differences in mathematical skills are typically explained by an innate capability to solve mathematical tasks. At the behavioural level this implies a consistent level of mathematical achievement that can be captured by strong relationships between tasks, as well as by a single statistical dimension that underlies performance on all mathematical tasks. To investigate this general assumption, the present study explored interrelations and dimensions of mathematical skills. For this purpose, 68 ten-year-old children from two schools were tested using nine mathematics tasks from the Basic Knowledge in Mathematics Test. Relatively low-to-moderate correlations between the mathematics tasks indicated most tasks shared less than 25% of their variance. There were four principal components, accounting for 70% of the variance in mathematical skill across tasks and participants. The high specificity in mathematical skills was discussed in relation to the principle of task specificity of learning.

Pacing and awareness: brain regulation of physical activity.

The aim of this current opinion article is to provide a contemporary perspective on the role of brain regulatory control of paced performances in response to exercise challenges. There has been considerable recent conjecture as to the role of the brain during exercise, and it is now broadly accepted that fatigue does not occur without brain involvement and that all voluntary activity is likely to be paced at some level by the brain according to individualised priorities and knowledge of personal capabilities. This article examines the role of pacing in managing and distributing effort to successfully accomplish physical tasks, while extending existing theories on the role of the brain as a central controller of performance. The opinion proposed in this article is that a central regulator operates to control exercise performance but achieves this without the requirement of an intelligent central governor located in the subconscious brain. It seems likely that brain regulation operates at different levels of awareness, such that minor homeostatic challenges are addressed automatically without conscious awareness, while larger metabolic disturbances attract conscious awareness and evoke a behavioural response. This supports the view that the brain regulates exercise performance but that the interpretation of the mechanisms underlying this effect have not yet been fully elucidated.

Postural responses during volitional and perturbed dynamic balance tasks in new lower limb amputees: a longitudinal study.

This study examined the adaptation of postural responses in transtibial amputees during both perturbed and volitional dynamic balance tasks during a five-month period following discharge from inpatient rehabilitation. Seven unilateral transtibial amputees performed the sensory organisation test (SOT) and the limits of stability (LOS) test protocols on the NeuroCom Equitest(®) at one, three and six months post-discharge from in-patient rehabilitation. Overall balance ability improved significantly (p=0.01) following discharge as did utilisation of somatosensory input (p=0.01), with hip strategy use decreasing. Reaction time and movement velocity did not change significantly in the majority of target directions for the LOS test. However, endpoint COG excursion and directional control were significantly increased in a number of directions (p≤0.05). Although balance ability improved following discharge from rehabilitation, participants were heavily reliant upon vision in order to maintain balance. Following discharge from rehabilitation, amputees were seemingly able to increase the spatial and accuracy aspects of volitional exploration of their LOS. However, temporal aspects did not display any adaptation, suggesting a trade-off between these aspects of postural control. Further practice of performing volitional postural movements under increasing time pressure, for example using low-cost gaming tools, may improve balance ability and postural control.

Pre-competitive confidence, coping, and subjective performance in sport.

The primary aim of this study was to investigate the relationship between confidence and subjective performance in addition to exploring whether coping mediated this relationship. A sample of 414 athletes completed a measure of confidence before performance. Athletes also completed a measure of coping and subjective performance after competing. Correlational findings revealed that confidence was positively and significantly associated with subjective performance. Furthermore, mediational analysis found that coping partly mediated this relationship. In particular, task-oriented coping (i.e., mental imagery) and disengagement-oriented coping (i.e., resignation) had positive and negative mediational effects, respectively. Additionally, athletes who employed mental imagery generally coped more effectively than those using resignation. These findings imply mental imagery has the potential not only to improve confidence, but also subsequent performance, while resignation coping may have the opposite effect. Overall, these results lend some credence to Vealey's integrated sports confidence model.

The facilitative nature of avoidance coping within sports injury rehabilitation.

Avoidance coping has commonly been reported within literature to be a debilitative process. However, in situations where goal attainment is reduced or eradicated avoidance coping strategies appear to have some benefit. The aim of this study was to identify the role of avoidance coping within the sports injury rehabilitation setting. A mixed methodological approach was utilized with four professional male rugby union players, concurrent with their rehabilitation from anterior cruciate ligament (ACL) surgery. Twice monthly interviews were conducted with each player, along with a self-report diary and the Coping with Health, Injuries and Problems (CHIP; Endler & Parker, 2000) inventory. Content analysis showed six higher-order themes split into two general dimensions: (a) behavioral avoidance coping (physical distraction, social interaction, maladaptive behaviors), and (b) cognitive avoidance coping (denial, thought stopping, cognitive distraction). Results suggest avoidance coping strategies facilitate control of short-term emotional states, as well has appearing to have long-term benefits for injured players. Particular benefits were associated with undertaking alternate work within the sports organization.

Relative torque profiles of elite male youth footballers: effects of age and pubertal development.

This study aimed to establish the effect of age and pubertal development on relative peak torque in youth footballers. One hundred and fifty-seven subjects were arranged into U12-U18 age groups; of these 133 also completed a self-reporting measure of pubertal development (PDS) and were grouped accordingly. Bilateral isokinetic testing included mean peak torque/body weight (PT/BW) and angle of peak torque (AoPT) for reps 2-4 of 5 in concentric quadriceps (CQ), concentric hamstrings (CH) and eccentric hamstrings (EH) at 60 degrees s(-1). Two minutes rest were provided between concentric and eccentric tests for both legs. A significant increase with age was noted for PT/BW in CQ, CH and EH (P<0.05), although POST HOC analyses revealed different patterns of significance dependent upon muscle and type of contraction. Specifically, the U18 s (CQ:2.20 nm/kg, CH:1.39 nm/kg, EH:2.16 nm/kg) were not significantly stronger than the U16 s and U15 s (CQ:2.42/2.29 nm/kg, CH:1.41/1.27 nm/kg, EH:2.22/2.15 nm/kg) even though they had entered full time training. The relationship between EH PT/BW and AoPT showed a weak but significant inverse correlation (P<0.001; R= -0.390 and -0.346 for dominant and non dominant legs). The findings of this study present unique football specific normative and age/PDS group data for PT/BW and AoPT, and the corresponding relationship between these variables.

Stressors and affective states among professional rugby union players.

The purpose of the present study was to examine (a) the sources of sport and non-sport stress and their associated symptoms on rest days, training days, and match days and (b) the temporal aspects of sources and symptoms of stress and affective states. Professional male rugby union players (n=16) completed the Daily Analysis of Life Demands in Athletes (DALDA) and the Activation Deactivation Adjective Check List (AD ACL) for 28 days. On match days players reported that few stressors were "worse than normal." Most stressors were "worse than normal" on training days followed by rest days and more stressors were "worse than normal" on the day after a match than on match days. Further, players reported an unpleasant, low activation state across the three analysis days, suggesting they were in an overtrained state. The findings of this study demonstrate that professional rugby players experience negative affect and a multitude of sport and non-sport stressors. Early detection of stressors and negative affective states could help prevent symptoms of overtraining and burnout and facilitate optimal training and sporting performance. Coaches and practitioners are encouraged to integrate the DALDA and AD ACL in their training and performance monitoring regimes.

Acute sport-related stressors, coping, and emotion among professional rugby union players during training and matches.

The purpose of this study was to examine acute sport-related stressors, coping, and emotion among a sample of professional rugby union players during training and matches. Five professional rugby union players maintained diaries for 31 days. The diaries consisted of a stressor checklist and an open-ended stressor response section, an open-ended coping response section, a Likert-type evaluation of coping effectiveness, a best-of-fit emotional response section, and a Likert-type evaluation of emotional intensity. Six out of the 10 stressors reported had a higher mean frequency in training compared with matches. Blocking was the most frequently cited coping strategy on match days, whereas increased concentration was the most frequently cited coping strategy on training days. Coping effectiveness was significantly higher during training compared with matches. Additionally, higher levels of emotional intensity were significantly associated with lower levels of coping effectiveness. Significant individual differences were found for both coping effectiveness and emotional intensity.

Adherence to sport injury rehabilitation programs: an integrated psycho-social approach.

The aim of the present study was to examine an adapted integrated psycho-social model to predict sport injury rehabilitation adherence. A longitudinal prospective design was used whereby 70 patients attending private physiotherapy clinics completed a battery of questionnaires both pre- and post-rehabilitation treatment based on the adapted framework. All participants were receiving treatment for tendonitis-related injuries. Adherence was monitored prospectively over the entire rehabilitation program using an observational measure of clinic adherence, a self-report measure of home-based adherence, in addition to monitoring attendance at rehabilitation sessions. In the initial phase of rehabilitation learning goal orientation, attitudes and perceived severity were found to predict rehabilitation intention. Intentions were also found to mediate the relationship between the aforementioned variables and clinic rehabilitation. Self-efficacy and self-motivation were predictors of clinic rehabilitation and attendance but not home rehabilitation. During the maintenance phase of rehabilitation coping ability and social support were predictors regarding all three measures of adherence. Implications for practitioners rehabilitating injured athletes are discussed.

The spatiotemporal structure of control variables during catching.

The discrepancy between traditional (force scaling models) and the more recently conceived dynamic explanations of load compensation (lambda model) was the departure point for the present study. By using the complex "open" motor skill of catching a ball--rather than the traditional "closed" skills--under "normal" (baseline) conditions and under conditions where a spring load was applied to the catching hand (thereby changing the dynamics of the skeletomuscular system) it was hoped to provide further clarification of this issue. Traditional force scaling models, in this respect, would predict that maximal closing velocity of the grasp action, and movement time would not be significantly different between a control and a spring-load condition. In contrast, a dynamic system perspective would maintain that spring loading would be compensated for by a change in the rate of shift of the reciprocal command (R-command). The obtained results showed a significant difference for conditions with regard to the maximal closing velocity of the grasp action, the baseline condition being higher than the two spring-load conditions. Furthermore, a significant difference was found for the aperture at moment of catch, the aperture at moment of catch being smaller in the baseline condition than that under the two spring-load conditions. With regard to the temporal variables, no significant differences were obtained. A comprehensive overall explanation of the obtained data in terms of the force scaling models was not realisable. It may be that findings supporting such theories are task specific and that for constrained tasks--such as catching a ball--different underlying organisational principles apply. The lambda model, however, could explain adequately the obtained results. It was concluded that, except for the preparatory phase associated with load compensation before the onset of the movement of the ball, the spatiotemporal structure of the control pattern underlying catching remains the same (invariant) in both baseline and load conditions. Thereby, the spatiotemporal structure of the resulting movement changes under the influence of the load and thus is not the same for load and baseline condition.