The effect of overnight sleep deprivation after competitive rugby league matches on postmatch physiological and perceptual recovery

PURPOSE: This study examined the effects of overnight sleep deprivation on recovery following competitive rugby league matches. METHODS: Eleven male, amateur rugby league players performed two competitive matches, followed by either a normal night's sleep (~8h; CONT) or a sleep deprived night (~0h; SDEP) in a randomised fashion. Testing was conducted the morning of the match, and immediately post-match, 2h post and the next morning (16h post-match). Measures included counter-movement jump (CMJ) distance, knee extensor maximal voluntary contraction (MVC), voluntary activation (VA), venous blood creatine kinase (CK) and C-reactive protein (CRP), perceived muscle soreness and a word-colour recognition cognitive function test. Percent change between post- and 16h post-match was reported to determine the effect of the intervention the next morning. RESULTS: Large effects indicated a greater post- to 16h post-match percentage decline in CMJ distance following SDEP compared to CONT (P=0.10-0.16; d=0.95-1.05). Similarly, the percentage decline in incongruent word-colour reaction times were increased in SDEP trials (P=0.007; d=1.75). Measures of MVC did not differ between conditions (P=0.40-0.75; d=0.13-0.33), though trends for larger percentage decline in VA were detected in SDEP (P=0.19; d=0.84). Further, large effects indicated higher CK and CRP responses 16h post-match during SDEP compared to CONT (P=0.11-0.87; d=0.80-0.88). CONCLUSIONS: Sleep deprivation negatively affected recovery following a rugby league match, specifically impairing CMJ distance and cognitive function. Practitioners should promote adequate post-match sleep patterns or adjust training demands the next day to accommodate the altered physical and cognitive state following sleep deprivation.

Methodological challenges in conducting a systematic review of community wide interventions to increase physical activity

Introduction: Evaluating the effectiveness of interventions designed to increase the physical activity in communities is often a difficult and complex task, requiring considerable expertise and investment, and often constrained by methodological limitations. These limitations, in turn, create additional challenges when these studies are used in systematic reviews as they hinder the confidence, precision and interpretation of results. The objective of this paper is to summarise the methodological challenges posed in conducting a systematic review of community-wide physical activity interventions to help inform those conducting future primary research and systematic reviews. Methods: We conducted a Cochrane systematic review of community-wide interventions to increase physical activity. We assessed the methodological quality of the included studies. We will investigate these in greater detail, particularly in relation to the potential impact on measures of effect, confidence in results, generalizability of results and general interpretation. Results: The systematic review was conducted and has been published in the Cochrane Library. A logic model was helpful in defining and interpreting the studies. Many studies of unsuitable study design were excluded; however several important methodological limitations of the primary studies evaluating community-wide physical activity interventions emerged. These included: - the failure to use validated tools to measure physical activity; - issues associated with pre and post test designs; - inadequate sampling of populations; - poor control groups; and - intervention and measurement protocols of inadequate duration. Although it is challenging to undertake rigorous evaluations of complex interventions, these issues result in significant uncertainty over the effectiveness of these interventions, and the possible factors required for a community-wide intervention to be successful. In particular, the combination of several of these limitations (e.g. un-validated tools, inadequate sampling, and short duration) is that studies may lack the sensitivity to detect any meaningful change. Multiple publications of findings for the same study also made interpretation difficult; however, interventions with parallel qualitative publications were helpful. Discussion: Evaluating community wide interventions to increase physical activity in a rigorous way is incredibly challenging. These findings reflect these challenges but have important ramifications for researchers conducting primary studies to determine the efficacy of such interventions, as well as for researchers conducting systematic reviews. This new review shows that the inadequacies of design and evaluation are continuing. It is hoped that the adoption of such suggestions may aid in the development of systematic reviews, but more importantly, in enabling translation of such findings into policy and practice.

On the prediction of simultaneous inbreeding coefficients at multiple loci

A new deterministic method for predicting simultaneous inbreeding coefficients at three and four loci is presented. The method involves calculating the conditional probability of IBD (identical by descent) at one locus given IBD at other loci, and multiplying this probability by the prior probability of the latter loci being simultaneously IBD. The conditional probability is obtained applying a novel regression model, and the prior probability from the theory of digenic measures of Weir and Cockerham. The model was validated for a finite monoecious population mating at random, with a constant effective population size, and with or without selfing, and also for an infinite population with a constant intermediate proportion of selfing. We assumed discrete generations. Deterministic predictions were very accurate when compared with simulation results, and robust to alternative forms of implementation. These simultaneous inbreeding coefficients were more sensitive to changes in effective population size than in marker spacing. Extensions to predict simultaneous inbreeding coefficients at more than four loci are now possible.

Validation of the Educational Stress Scale for Adolescents (ESSA) in Vietnam

Introduction To date, there has been little systematic, quantitative research on the links between academic pressure and mental health among adolescents in Asia, and none in Vietnam. In part, this is because of a lack of appropriate tools to measure this complex phenomenon. This study was to validate the Educational Stress Scale for Adolescents (ESSA), developed and tested in China, with the aim of fostering further research in Asia. Methods A total of 1283 students were recruited in 3 secondary schools and 3 high schools in Ho Chi Minh City, Vietnam. Anonymous, selfreport questionnaires included the ESSA and previously validated measures of mental health. Results Among the 1226 questionnaires available, 54% of respondents were female. The mean age was 15.3 years. Students reported substantial study burden. The ESSA had good internal consistency, and factorial validity and concurrent validity were established. Conclusion The ESSA is a suitable measure for school-based mental health research in Asia.

Early adolescents’ helping behaviours when a friend is injured in a fight : the role of an extended Theory of Planned Behavior

This paper examines the role of first aid training in increasing adolescent helping behaviours when taught in a school-based injury prevention program, Skills for Preventing Injury in Youth (SPIY). The research involved the development and application of an extended Theory of Planned Behaviour (TPB), including “behavioural willingness in a fight situation,” “first aid knowledge” and “perceptions of injury seriousness”, to predict the relationship between participation in SPIY and helping behaviours when a friend is injured in a fight. From 35 Queensland high schools, 2500 Year 9 students (mean age = 13.5, 40% male) completed surveys measuring their attitudes, perceived behavioural control, subjective norms and behavioural intention, from the TPB, and added measures of behavioural willingness in a fight situation, perceptions of injury seriousness and first aid knowledge, to predict helping behaviours when a friend is injured in a fight. It is expected that the TPB will significantly contribute to understanding the relationship between participation in SPIY and helping behaviours when a friend is injured in a fight. Further analyses will determine whether the extension of the model significantly increases the variance explained in helping behaviours. The findings of this research will provide insight into the critical factors that may increase adolescent bystanders’ actions in injury situations.

Agility of the firm : customer's perspective

Agility is emerging as an important determinant of success and achieving sustained competitive advantage in hyper-competition. Whilst the digital natives are on the rise, ubiquitous technologies, networks and associated systems are increasingly weaving themselves into the very fabric of everyday life of both individuals and corporations. With a global shift towards “everywhere retailing”, ubiquitous contemporary information systems such as mobile CRM systems (C-CRMS) are evolving. Unlike in traditional CRMS, customers are becoming an important user group in this new paradigm. Draws on agility literature, this study examine how customers’ use of C-CRMS influence firm’s customer sensing capability, firm’s customer responding capability, and how customer-perceived firm’s responsiveness influence customers use of C-CRMS. Following the notions of agility we theorized firm’s customer agility from customers’ standpoint where we use customers’ use of C-CRMS and customer-perceived firm’s responsiveness for sensing and responding components of agility respectively. This research-in-progress paper investigates how C-CRMS facilitates firm’s customer agility, and reports the approach pursued in adopting sense and response measures of customer agility taking the customers perspective derived through extant literature.

Effects of changes to child car restraint legislation in Australia on seating position and restraint use

Road trauma is a leading cause of child injury worldwide and in highly motorised countries, injury as a passenger represents a major proportion of all child road deaths and hospitalisations. Australia is no exception, particularly since motorised transport to school is at high levels in most Australian states. Recently the legislation governing the type of car restraints required for children aged under 7 years has changed in most Australian states aligning requirements better with accepted best practice. However, it is unclear what effect these changes have had on children’s seating positions or the types of restraints used. A mixed methods evaluation of the impact of the new legislation on compliance was conducted at three times: baseline (Time 1); after announcement that changes were going to be implemented but before enforcement began (Time 2); and after enforcement commenced (Time 3). Measures of compliance were obtained using two methods: road-side observations of vehicles with child passengers; and parental self-report (intercept interviews conducted at Time 2 and Time 3 only). Results from the observations suggested an overall positive effect. Proportions of children occupying front seats decreased overall and use of dedicated child seas increased to almost 40% of the observed children by Time 3. However, almost a quarter of the children observed were still occupying the front seat. These results were very different from those of the interview study where almost no children were reported as usually travelling in the front seat, and the reported use of dedicated restraints with children was almost 90%, more than twice that in the observations.

Individual, environmental, and meteorological predictors of daily personal ultraviolet radiation exposure measurements in a United States cohort study

Background Individual exposure to ultraviolet radiation (UVR) is challenging to measure, particularly for diseases with substantial latency periods between first exposure and diagnosis of outcome, such as cancer. To guide the choice of surrogates for long-term UVR exposure in epidemiologic studies, we assessed how well stable sun-related individual characteristics and environmental/meteorological factors predicted daily personal UVR exposure measurements. Methods We evaluated 123 United States Radiologic Technologists subjects who wore personal UVR dosimeters for 8 hours daily for up to 7 days (N = 837 days). Potential predictors of personal UVR derived from a self-administered questionnaire, and public databases that provided daily estimates of ambient UVR and weather conditions. Factors potentially related to personal UVR exposure were tested individually and in a model including all significant variables. Results The strongest predictors of daily personal UVR exposure in the full model were ambient UVR, latitude, daily rainfall, and skin reaction to prolonged sunlight (R2 = 0.30). In a model containing only environmental and meteorological variables, ambient UVR, latitude, and daily rainfall were the strongest predictors of daily personal UVR exposure (R2 = 0.25). Conclusions In the absence of feasible measures of individual longitudinal sun exposure history, stable personal characteristics, ambient UVR, and weather parameters may help estimate long-term personal UVR exposure.

Self-regulated learning and executive function : exploring the relationships in a sample of adolescent males

This study investigated relationships between SRL and EF in a sample of 254 school-aged adolescent males. Two hypotheses were tested: that self-reported measures of SRL and EF are closely related and that as different aspects of EF mature during adolescence, the corresponding components of SRL should also improve, leading to an age-related increase in the correlation between EF and SRL. Two self-report instruments were used: the strategies for self-regulated learning survey (SSRLS) and the behavioural rating instrument of executive function (BRIEF). Strong correlations between the measures of EF and SRL were found, especially in areas associated with metacognitive processes. Correlations between EF and SRL were found, with weaker correlations between behavioural regulation and SRL were found to be weaker for the younger participants in the sample while the relationship between EF and SRL appears to grow stronger during the initial years of high school even though self-reported levels of EF along with motivation for SRL and important components of SRL such as goal setting and planning were found to decrease with age. Decreasing levels of motivation for learning during adolescence are speculated to moderate the deployment of SRL and EF in a school context.

Towards a capabilities database to inform inclusive design : Experimental investigation of effective survey-based predictors of human-product interaction

A key issue in the field of inclusive design is the ability to provide designers with an understanding of people's range of capabilities. Since it is not feasible to assess product interactions with a large sample, this paper assesses a range of proxy measures of design-relevant capabilities. It describes a study that was conducted to identify which measures provide the best prediction of people's abilities to use a range of products. A detailed investigation with 100 respondents aged 50-80 years was undertaken to examine how they manage typical household products. Predictor variables included self-report and performance measures across a variety of capabilities (vision, hearing, dexterity and cognitive function), component activities used in product interactions (e.g. using a remote control, touch screen) and psychological characteristics (e.g. self-efficacy, confidence with using electronic devices). Results showed, as expected, a higher prevalence of visual, hearing, dexterity, cognitive and product interaction difficulties in the 65-80 age group. Regression analyses showed that, in addition to age, performance measures of vision (acuity, contrast sensitivity) and hearing (hearing threshold) and self-report and performance measures of component activities are strong predictors of successful product interactions. These findings will guide the choice of measures to be used in a subsequent national survey of design-relevant capabilities, which will lead to the creation of a capability database. This will be converted into a tool for designers to understand the implications of their design decisions, so that they can design products in a more inclusive way.

Sensitivity of edge detection methods for quantifying cell migration assays

Quantitative imaging methods to analyze cell migration assays are not standardized. Here we present a suite of two–dimensional barrier assays describing the collective spreading of an initially–confined population of 3T3 fibroblast cells. To quantify the motility rate we apply two different automatic image detection methods to locate the position of the leading edge of the spreading population after 24, 48 and 72 hours. These results are compared with a manual edge detection method where we systematically vary the detection threshold. Our results indicate that the observed spreading rates are very sensitive to the choice of image analysis tools and we show that a standard measure of cell migration can vary by as much as 25% for the same experimental images depending on the details of the image analysis tools. Our results imply that it is very difficult, if not impossible, to meaningfully compare previously published measures of cell migration since previous results have been obtained using different image analysis techniques and the details of these techniques are not always reported. Using a mathematical model, we provide a physical interpretation of our edge detection results. The physical interpretation is important since edge detection algorithms alone do not specify any physical measure, or physical definition, of the leading edge of the spreading population. Our modeling indicates that variations in the image threshold parameter correspond to a consistent variation in the local cell density. This means that varying the threshold parameter is equivalent to varying the location of the leading edge in the range of approximately 1–5% of the maximum cell density.

Footprint-based estimates of arch structure are confounded by body composition in adults

Previous research employing indirect measures of arch structure, such as those derived from footprints, have indicated that obesity results in a “flatter” foot type. In the absence of radiographic measures, however, definitive conclusions regarding the osseous alignment of the foot cannot be made. We determined the effect of body mass index (BMI) on radiographic and footprint‐based measures of arch structure. The research was a cross‐sectional study in which radiographic and footprint‐based measures of foot structure were made in 30 subjects (10 males, 20 female) in addition to standard anthropometric measures of height, weight, and BMI. Multiple (univariate) regression analysis demonstrated that both BMI ( β  = 0.39, t 26  = 2.12, p  = 0.04) and radiographic arch alignment ( β  = 0.51, t 26  = 3.32, p  < 0.01) were significant predictors of footprint‐based measures of arch height after controlling for all variables in the model ( R 2  = 0.59, F 3,26  = 12.3, p  < 0.01). In contrast, radiographic arch alignment was not significantly associated with BMI ( β  = −0.03, t 26  = −0.13, p  = 0.89) when Arch Index and age were held constant ( R 2  = 0.52, F 3,26  = 9.3, p  < 0.01). Adult obesity does not influence osseous alignment of the medial longitudinal arch, but selectively distorts footprint‐based measures of arch structure. Footprint‐based measures of arch structure should be interpreted with caution when comparing groups of varying body composition.

Measuring mechanical properties of tendon in vivo

Introduction: Understanding the mechanical properties of tendon is an important step to guiding the process of improving athletic performance, predicting injury and treating tendinopathies. The speed of sound in a medium is governed by the bulk modulus and density for fluids and isotropic materials. However, for tendon,which is a structural composite of fluid and collagen, there is some anisotropy requiring an adjustment for Poisson’s ratio. In this paper, these relationships are explored and modelled using data collected, in vivo, on human Achilles tendon. Estimates for elastic modulus and hysteresis based on speed of sound data are then compared against published values from in vitro mechanical tests. Methods: Measurements using clinical ultrasound imaging, inverse dynamics and acoustic transmission techniques were used to determine dimensions, loading conditions and longitudinal speed of sound for the Achilles tendon during a series of isometric plantar flexion exercises against body weight. Upper and lower bounds for speed of sound versus tensile stress in the tendon were then modelled and estimates derived for elastic modulus and hysteresis. Results: Axial speed of sound varied between 1850 to 2090 m.s−1 with a non-linear, asymptotic dependency on the level of tensile stress in the tendon 5–35 MPa. Estimates derived for the elastic modulus ranged between 1–2 GPa. Hysteresis derived from models of the stress-strain relationship, ranged from 3–11%. These values agree closely with those previously reported from direct measurements obtained via in vitro mechanical tensile tests on major weight bearing tendons. Discussion: There is sufficiently good agreement between these indirect (speed of sound derived) and direct (mechanical tensile test derived) measures of tendon mechanical properties to validate the use of this non-invasive acoustic transmission technique. This non-invasive method is suitable for monitoring changes in tendon properties as predictors of athletic performance, injury or therapeutic progression.

The acute transverse strain response of the patellar tendon to quadriceps exercise

Introduction: The human patellar tendon is highly adaptive to changes in habitual loading but little is known about its acute mechanical response to exercise. This research evaluated the immediate transverse strain response of the patellar tendon to a bout of resistive quadriceps exercise. Methods: Twelve healthy adult males (mean age 34.0+/-12.1 years, height 1.75+/-0.09 m and weight 76.7+/-12.3 kg) free of knee pain participated in the research. A 10-5 MHz linear-array transducer was used to acquire standardised sagittal sonograms of the right patellar tendon immediately prior to and following 90 repetitions of a double-leg parallel-squat exercise performed against a resistance of 175% bodyweight. Tendon thickness was determined 20-mm distal to the pole of the patellar and transverse Hencky strain was calculated as the natural log of the ratio of post- to pre-exercise tendon thickness and expressed as a percentage. Measures of tendon echotexture (echogenicity and entropy) were also calculated from subsequent gray-scale profiles. Results: Quadriceps exercise resulted in an immediate decrease in patellar tendon thickness (P<.05), equating to a transverse strain of -22.5+/-3.4%, and was accompanied by increased tendon echogenicity (P<.05) and decreased entropy (P<.05). The transverse strain response of the patellar tendon was significantly correlated with both tendon echogenicity (r = -0.58, P<.05) and entropy following exercise (r=0.73, P<.05), while older age was associated with greater entropy of the patellar tendon prior to exercise (r=0.79, P<.05) and a reduced transverse strain response (r=0.61, P<.05) following exercise. Conclusions: This study is the first to show that quadriceps exercise invokes structural alignment and fluid movement within the matrix that are manifest by changes in echotexture and transverse strain in the patellar tendon., (C)2012The American College of Sports Medicine

Chaotic soul - messy heart : the phenomenon of experiencing auditory hallucinations

Globally, it is estimated that 24 million people live with schizophrenia (WHO, 2008), while 1.2 million people have been diagnosed with schizophrenia in Indonesia. Auditory hallucinations are a key symptom of schizophrenia according to the DSM IV-TR (Frances, First, & Pincus, 2002). It is estimated that the prevalence of auditory hallucinations in people with schizophrenia range from 64.3% to 83.4% (Thomas et al., 2007). Until recently, the majority of studies were conducted in Western societies the primary focus of which, has been on the causes and treatments of auditory hallucinations (Walton, 1999) and on the biological and cognitive aspects of the phenomenon (Changas, Garcia-Montes, de Lemus & Olivencia, 2003). While a few studies have explored the lived experience of people with schizophrenia, there is little research about the experience of auditory hallucinations. Therefore, the focus of this study was on an exploration of the experience of auditory hallucinations as described by Indonesian people living with schizophrenia. Based on the available literature, there have been no published qualitative studies relating to the lived experience of auditory hallucinations as described by Indonesian people diagnosed with schizophrenia. Husserlian descriptive phenomenological approach was applied in explicating the phenomenon of auditory hallucinations in this study. In-depth audio-taped interviews were conducted with 13 participants. Analysis of participant transcripts was undertaken using Colaizzi.s (1973) approach. Eight major themes were explicated: Feeling more like a robot than a human being - feeling compelled to respond to auditory hallucinations; voices of contradiction - a point of confusion; a frightening experience, the voices emerged at times of loss and grief; disruption to daily living; tattered relationships and family disarray; finding a personal path to living with auditory hallucinations; seeking relief in Allah through prayer and ritual. Experiencing auditory hallucinations for people diagnosed with schizophrenia is a journey of challenges as each individual struggles to understand their now changed life-world, reconstruct a sense of meaning within their illness experience, and to carve out a pathway to wellness. The challenge for practitioners is to learn from those who have experienced auditory hallucinations, to be with them in their journey of recovery and wellness, and to apply a person-centered approach to care within the context of a multidisciplinary team.