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Players involved in the various football codes compete throughout the calendar year around the world. Therefore, environmental stressors such as temperature and altitude should be considered in preparation for, and during, matches. We aimed to systematically review the observational and quasi-experimental studies that have been specifically designed to quantify the effects of temperature (hot or cold) high altitude on in-match physical performance indicators. A search of electronic databases (Web of Science, Scopus, SPORTDiscus, PubMed/MEDLINE) was conducted, resulting in 19,424 papers being identified as relevant. Following sifting in relation to the eligibility criteria, 12 papers were deemed directly relevant. The reviewed studies scored 6-9 (on a 0-9 scale) for quality assessment using a previously used scale. The major outcome variables relevant to the current review were total distance (m), high speed running (m) and high-speed runs (count) measured during matches. Standardized effect sizes (ES) were heterogeneous across studies for total distance (ES: -0.96 to -0.14) and high-speed running (ES: -0.69 to 0.12) for >1000 m vs sea-level, time spent at the given altitude being a putative factor for this heterogeneity. Heat had mainly detrimental effects on performance, but ES were, again, heterogeneous across studies (ES: -1.25 to 0.26), dependent on temperature. Given the small number of studies that only involved mostly male athletes, and large heterogeneity across studies, more research needs be conducted on physical performance in these environmental conditions, with attention paid to standardizing outcomes and broadening the approaches of studies to guide future decision making in professional sporting environments.

IMPORTANCE: Gamma irradiation of leukoreduced red blood cells (RBCs) prevents transfusion-associated graft-vs-host disease but also exacerbates storage lesion formation in RBCs. It is unknown whether freshly irradiated RBCs are more efficacious than irradiated and stored RBCs in preterm infants with high transfusion requirements. OBJECTIVE: To examine whether transfusion of freshly irradiated vs irradiated and stored RBC components improves cerebral oxygen delivery in preterm infants with anemia. DESIGN, SETTING, AND PARTICIPANTS: This single-center, double-blinded, proof-of-concept randomized clinical trial was conducted at the neonatal intensive care unit of Wellington Regional Hospital in Wellington, New Zealand, between December 1, 2017, and November 30, 2018. Participants were preterm infants (

Objective The aims of this study were to quantify the effects of spinal mobilization on force production, failure point, and muscle activity of the hamstrings during the Nordic hamstring exercise (NHE), and to explore individual differences in responses. Methods In a replicated randomized crossover trial, 24 asymptomatic, recreationally active men (age [mean ± standard deviation]: 27 ± 6 years; body mass: 82 ± 17 kg; height: 181 ± 8 cm) completed 2 standardized intervention trials (L4/5 zygapophyseal mobilizations) and 2 control trials. The failure point of the NHE was determined with 3D motion capture. Peak force, knee flexor torque, and electromyography (EMG) of the biceps femoris were measured. Data analyses were undertaken to quantify mean intervention response and explore any individual response heterogeneity. Results Mean (95% confidence interval) left-limb force was higher in intervention than in control trials by 18.7 (4.6-32) N. Similarly, right-limb force was higher by 22.0 (3.4-40.6) N, left peak torque by 0.14 (0.06-0.22) N • m, and right peak torque by 0.14 (0.05-0.23) N • m/kg. Downward force angle was decreased in intervention vs control trials by 4.1° (0.5°-7.6°) on the side of application. Both peak EMG activity (P = .002), and EMG at the downward force (right; P = .020) increased in the intervention condition by 16.8 (7.1-26.4) and 8.8 (1.5-16.1) mV, respectively. Mean downward acceleration angle changed by only 0.3° (−8.9° to 9.4°) in intervention vs control trials. A clear response heterogeneity was indicated only for right force (Participant × Intervention interaction: P = .044; response heterogeneity standard deviation = 34.5 [5.7-48.4] N). Individual response heterogeneity was small for all other outcomes. Conclusion After spinal mobilization, immediate changes in bilateral hamstring force production and peak torque occurred during the NHE. The effect on the NHE failure point was unclear. Electromyographic activity increased on the ipsilateral side. Response heterogeneity was generally similar to the random trial-to-trial variability inherent in the measurement of the outcomes.

Objective: Using a formative evaluation of a high-intensity interval training (HIIT) intervention, we illustrate how qualitative data can inform the development of workplace exercise interventions. Method: Eight focus groups and four interviews were conducted with employees (n = 38) and management (n = 4) from six office-based organisations before intervention implementation. Results: Some participants thought workplace-based HIIT would be practical, given the limited time required. Others perceived it may not be acceptable for all individuals, given the exercise intensity. With consideration of identified barriers (workload/family commitments effecting time availability) and facilitators (flexible working conditions) participants' perspectives were incorporated into the intervention protocol. A short-term group-based intervention was preferred, with a choice of exercise modes (based on stair climbing, stepping or boxing). Conclusion: This study provides a framework to incorporate stakeholders' perspectives into the development of workplace exercise interventions. usc Refereed/Peer-reviewed

La guia CONSORT (CONsolidated Standards Of Reporting Trials)de 2010 (http://www.consort-statement.org/consort-2010) fuedesarrollada para mejorar el informe de ensayos clinicoscontrolados aleatorios de grupos paralelos, por lo que elcumplimiento de los estandares establecidos se puede demostrarmediante la cumplimentacion de la lista de chequeo CONSORT20101. Las principales revistas medicas han respaldado estainiciativa, que sin duda ha mejorado la realizacion y el informe deresultados de la investigacion clinica y sanitaria. La investigacionen el campo de la nutricion deportiva y el metabolismo delejercicio se beneficiara de estandares similares, pero comunmenteutiliza disenos de investigacion diferentes a los ensayos clinicos degrupos paralelos, como los experimentos cruzados.Se ha publicado recientemente una ampliacion de CONSORT queaborda ensayos cruzados aleatorios2, con una lista de verificacionrevisada que se centra en cuestiones de primera relevancia paraensayos clinicos que abordan tratamientos medicos o deasistencia medica. Sin embargo, estas cuestiones especificas de losensayos clinicos, pueden tener una relevancia diferente, cuando seconsideran en relacion con los experimentos mecanicistas,estrictamente controlados, realizados en laboratorio, que sonhabituales en la ciencia del ejercicio. Por ejemplo, los disenoscruzados pueden implicar efectos de orden entre evaluaciones; enlos ensayos clinicos, esto suele ocurrir con mayor frecuenciadebido al tratamiento o la intervencion en si, lo que requiere unintervalo de lavado suficiente, antes de repetir las evaluaciones.Por el contrario, la tendencia en la investigacion sobre nutriciondeportiva, se relaciona comunmente con la evaluacion en simisma, que a menudo, tiende a ser mas invasiva o exigente para elparticipante, que una instantanea sobre su estado de salud. Dehecho, las pruebas fisicas de rendimiento humano sonparticularmente propensas a efectos de aprendizaje o fatiga eincluso algunas adaptaciones fisicas pueden persistir durantesemanas o meses despues del primer test. Por ejemplo, eldenominado “efecto de intentos repetidos”, que describe como unasola exposicion a un ejercicio fisico desacostumbrado que producedano muscular puede inducir una profunda y duradera proteccionante ejercicios similares en el futuro3,4. Los participantes enensayos de ejercicio tambien pueden ser atletas de elite, cuyosniveles habituales de actividad fisica (y dieta) pueden mostrarvariaciones profundas a lo largo del tiempo (es decir,periodizacion), lo que complica aun mas la interpretacion deestudios longitudinales.La lista de chequeo PRESENT (Proper Reporting of Evidence inSport & Exercise Nutrition Trials) 2020 (Ver Anexo), por tanto, seha adaptado de la guia CONSORT para abordar especificamente lacombinacion unica de desafios y oportunidades que enfrentan losinvestigadores dentro de los amplios campos de la nutriciondeportiva y el metabolismo del ejercicio. El presente documentocomplementa y desarrolla la lista de verificacion CONSORT alponer enfasis y proveer ejemplos comunes o de mayor relevanciapara la investigacion en esta area tematica. La lista decomprobacion PRESENT 2020 se diseno teniendo en cuenta lanecesidad de minimizar a los autores la sobrecarga que suponeasegurarse de que el informe de sus resultados cumpla con losrequisitos de calidad; deberia permitir a los investigadoresdeterminar rapidamente si toda la informacion relevante estaincluida en su manuscrito. Por supuesto, es posible cumplir contodos los factores en la lista de verificacion a pesar de haberrealizado un mal estudio y/o haber informado mal de un buenestudio, mientras que algunos elementos de la lista de chequeopueden no ser aplicables incluso para investigacionesrigurosamente realizadas. No obstante, la consideracion ydiscusion de los factores identificados en la lista de chequeodeberia mejorar la comunicacion de los resultados de lainvestigacion relacionada con el ejercicio y la nutricion, en elfuturo inmediato, y tiene el potencial de mejorar el diseno y larealizacion de ensayos a largo plazo.

Study Design. Non-randomised longitudinal observational study. Objective. To evaluate the association between baseline pain duration and medium-to-long term clinical outcomes, in low back pain (LBP) patients enrolled on the North East of England Regional Back Pain and Radicular Pain Pathway (NERBPP). Summary of Background Data. The NERBPP is based upon National Institute for Health and Care Excellence (NICE) guidelines. These guidelines no longer differentiate management of LBP patients based on pain duration. Medium-to-long term data from the NERBPP is lacking. Methods. Between May 2015 and December 2019, 786 and 552 LBP patients from the NERBPP returned 6-month and 12-month follow-up outcome measures, respectively. Outcomes included pain (Numerical rating scale), function (Oswestry Disability Index) and quality-of-life (EuroQol five-dimension, five-level questionnaire), analysed using a series of covariate-adjusted models. Patients were categorized into four groups based upon baseline pain duration

BackgroundPeople with chronic obstructive pulmonary disease (COPD) are four times more likely to fall than healthy peers, leading to increased morbidity and mortality. Poor balance is a major risk factor for falls. This review aims to quantify the extent of balance impairment in COPD, and establish contributing clinical factors, which at present are sparse.MethodsFive electronic databases were searched, in July 2017 and updated searches were performed in March 2019, for studies comparing balance in COPD with healthy controls. Meta-analyses were conducted on sample mean differences (MD) and reported correlations between balance and clinical factors. Meta-regression was used to quantify the association between mean difference in percentage predicted forced expiratory volume in 1 s (FEV1) and mean balance impairment. Narrative summaries were provided where data were insufficient for meta-analysis.ResultsTwenty-three studies were included (n=2751). Meta-analysis indicated COPD patients performed worse than healthy controls on timed up and go (MD=2.77 s, 95% CI 1.46 s to 4.089 s, p=1 and balance were negligible (r2 =ConclusionsCompared with healthy controls, people with COPD have a clinically meaningful balance reduction, which may be related to reduced muscle strength, physical activity and exercise capacity. Our findings support a need to expand the focus of pulmonary rehabilitation to include balance assessment and training, and further exploration of balance impairment in COPD.PROSPERO registration numberCRD4201769041

The purpose of this study was to present reference standards for physical performance test outcomes relevant to elite female soccer players. We analysed mixed-longitudinal data (n = 1715 observations) from a sample of 479 elite youth and senior players as part of the English Football Association's national development programme (age range: 12.7 to 36.0 years). Semi-parametric generalized additive models for location, scale and shape (GAMLSS) estimated age-related reference centiles for 5-m sprinting, 30-m sprinting, countermovement jump (CMJ) height, and Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1) performance. The estimated reference centiles indicated that the median of the distribution of physical performance test scores varied non-linearly with advancing chronological age, improving until around 25 years for each performance variable. These are the first reference ranges for performance test outcomes in elite English female soccer players. These data can assist practitioners when interpreting physical test performance outcomes to track an individual's progress over time and support decision-making regarding player recruitment and development.

Objective: To examine training and match loads undertaken by soccer players competing in the English Premier League.Methods: Using a retrospective design, external (GPS) and internal training loads...

Background: \ud After meal ingestion, a series of coordinated hormone responses occur concomitantly with changes in perceived appetite. It is not known whether interindividual variability in appetite exists in response to a meal.\ud \ud Objectives: \ud The aim of this study was to 1) assess the reproducibility of appetite responses to a meal; 2) quantify individual differences in responses; and 3) explore any moderating influence of the fat mass and obesity associated (FTO) gene.\ud \ud Methods: \ud Using a replicated crossover design, 18 healthy men (mean ± SD age: 28.5 ± 9.8 y; BMI: 27.0 ± 5.0 kg/m2) recruited according to FTO genotype (9 AA, 9 TT) completed 2 identical control and 2 identical standardized meal conditions (5025 kJ) in randomized sequences. Perceived appetite and plasma acylated ghrelin, total peptide YY (PYY), insulin, and glucose concentrations were measured before and after interventions as primary outcomes. Interindividual differences were explored using Pearson's product-moment correlations between the first and second replicates of the control-adjusted meal response. Within-participant covariate-adjusted linear mixed models were used to quantify participant-by-condition and genotype-by-condition interactions.\ud \ud Results: \ud The meal suppressed acylated ghrelin and appetite perceptions [standardized effect size (ES): 0.18–4.26] and elevated total PYY, insulin, and glucose (ES: 1.96–21.60). For all variables, SD of change scores was greater in the meal than in the control conditions. Moderate-to-large positive correlations were observed between the 2 replicates of control-adjusted meal responses for all variables (r = 0.44–0.86, P ≤ 0.070). Participant-by-condition interactions were present for all variables (P ≤ 0.056). FTO genotype-by-condition interactions were nonsignificant (P ≥ 0.19) and treatment effect differences between genotype groups were small (ES ≤ 0.27) for all appetite parameters.\ud \ud Conclusions: \ud Reproducibility of postprandial appetite responses is generally good. True interindividual variability is present beyond any random within-subject variation in healthy men but we detected no moderation by the FTO genotype. These findings highlight the importance of exploring individual differences in appetite for the prevention and treatment of obesity. This trial was registered at clinicaltrials.gov as NCT03771690.

Background: Standing on textured materials can improve static balance, potentially by modulating somatosensory inputs from the soles of the feet.Research question: To synthesise and quantify the immediate effects of textured materials on static balance in healthy young and older adults.Methods: Primary outcomes were the centre of pressure (COP) displacement and velocity, during eyes open and eyes closed conditions. Ten crossover studies (n = 318, 58% female) met the inclusion criteria. A random effects meta-analysis model derived pooled standardised mean differences (SMD; Hedges g) to quantify the effects of textured materials. Heterogeneity was quantified with the tau-statistic (tau). A 95% prediction interval quantified the likely range of true effects on COP outcomes in similar future studies.Results: There was a small to moderate beneficial effect for textured materials vs control conditions in: COP displacement during both eyes open (SMD: 0.29; 95% CI -0.06 to 0.64; tau = 0.32) and eyes closed (SMD: 0.75; 95% CI 0.18 to 1.33; tau = 0.55). A trivial to small beneficial effect was observed in COP velocity during eyes open (SMD: 0.14; 95% CI -0.14 to 0.43; tau = 0.18) and eyes closed (SMD: 0.20; 95% CI 0.01 to 0.40; tau = 0.18) for textured materials. The 95% prediction intervals showed texture may not consistently provide beneficial results across studies for all outcomes: COP displacement EC (-0.61 to 2.12), EO (-0.54 to 1.12), COP velocity EC (-0.27 to 0.68) and EO (-0.44 to 0.73).Significance: Overall, textured materials improved balance, but these effects were heterogeneous. This research may therefore inform applied investigations into balance improvements for healthy populations, for example, in functional movements and sports. usc Refereed/Peer-reviewed

Wright, MD and Atkinson, G. Changes in sprint-related outcomes during a period of systematic training in a girls' soccer academy. J Strength Cond Res 33(3): 793-800, 2019-The longitudinal tracking of performance indicators is lacking during the training of young female soccer players. Therefore, changes in 5-m acceleration, 20-m speed, change-of-direction (COD) speed, and repeated-sprint ability (RSA) were quantified during a 3-year period in an English Football Association Center of Excellence. Fourteen players (mean age = 12.1 years, SD = ±0.9) were recruited, and their best performance scores from preseason and in-season testing were averaged. Players were typically exposed to soccer (2 × 90 minutes per week) and strength and conditioning training (1 × 70 minutes per week) and played 20 soccer matches (50-80 minutes) during 35-week seasons. Mean (±90% confidence limits (CL)) overall improvements over the 3 years were 5.9% (1.3) (most likely large) for speed, 4.0% (1.0) (most likely large) for RSA, 8.8% (1.1) for acceleration, and 8.3% (1.4) for COD speed (both most likely very large). Improvements between years one and 2 ranged from most likely moderate to very large. Further small improvements in COD speed and 20-m speed (both likely) were observed between years 2 and 3. Individual differences in response were apparent only for COD speed, which were moderate and small between years 2 and 3. Most likely very large to near-perfect within-player correlations were observed between maturation and sprint measures. These data from a single-arm longitudinal study indicate that systematic exposure to training, which includes one dedicated strength and conditioning session each week, is associated with improvements in sprint-related physical qualities in girls.

Introduction: Valid and informed interpretations of changes in physical performance test data are important within athletic development programmes. At present, there is a lack of consensus regarding a suitable method for deeming whether a change in physical performance is practically relevant or not.\ud \ud Methods: We compared true population variance in mean test scores between those derived from evidence synthesis of observational studies to those derived from practioner opinion (n = 30), and to those derived from a measurement error (minimal detectable change) quantification (n = 140). All these methods can help to obtain ‘target’ change score values for performance variables.\ud \ud Results: We found that the conventional ‘blanket’ target change of 0.2 (between-subjects SD) systematically underestimated practically relevant and more informed changes derived for 5-m sprinting, 30-m sprinting, CMJ, and Yo-Yo Intermittent Recovery Level 1 (IR1) tests in elite female soccer players.\ud \ud Conclusions: For the first time in the field of sport and exercise sciences, we have illustrated the use of a principled approach for comparing different methods for the definition of changes in physical performance test variables that are practically relevant. Our between-method comparison approach provides preliminary guidance for arriving at target change values that may be useful for research purposes and tracking of individual female soccer player’s physical performance.

Pain is a significant health burden globally and its management frequently fails to comply with evidence based, biopsychosocial guidelines. This may be partly attributable to inadequate biopsychosocial focussed pain education for students and clinicians. We aimed to undertake a systematic review, using Cochrane methodology, of randomized controlled trials with meta-analysis to quantify the effects of biopsychosocial education strategies in changing student/qualified health care professionals (HCPs) pain related attitudes, knowledge, clinical behaviour or patient outcomes. A systematic search of the literature was undertaken using CINAHL, AMED, PEDro, Cochrane Central Library, MEDLINE, ScienceDirect, Rehabdata, SportDiscus, EMBASE, ASSIA, Dentistry and Oral Science, Psycinfo, Education Research Complete and OpenGrey from 1977 to November 2020. Pooled effect sizes were quantified in random effects meta-analyses for attitudes, knowledge, and clinical behaviors. From a sample of 1812 records, 6 were narratively analysed and 15 were included in the meta-analyses. These studies represented 3022 patients and 3163 HCPs and students. Education improved attitudes by 11.3% (95% confidence interval: 2.2–20.4%, P = .02), and knowledge by 18.8% (12.4–25.3%, P = .01). The effects of education on clinical behavior favoured a clinically relevant improvement (OR = 2.4, 0.9–5.9, P = .06). Narrative analysis of the effect of biopsychosocial education for student HCPs/HCPs upon patient outcomes was inconclusive. These findings demonstrate that biopsychosocial focussed pain education strategies can improve student/qualified HCPs’ pain related knowledge and attitudes and increase the likelihood that they will behave more in keeping with evidence-based practice. This should result in improved patient outcomes, however, evidence to support or refute this is lacking. PROSPERO systematic review record number, CRD42018082251. Perspective: We outline the effectiveness of biopsychosocial pain education for health care professionals and students in improving pain knowledge, attitudes, and evidence-based behaviors. These improvements should enhance clinical outcomes in patients with pain but further evidence is needed to confirm this.

BACKGROUND Sensory discrimination training (SDT) is a form of feedback guided sensory training used in the treatment of chronic musculoskeletal pain (CMP). OBJECTIVE This systematic review aimed to investigate the efficacy and safety of SDT for CMP. METHODS MEDLINE, CINAHL, EMBASE, AMED, CENTRAL, PsycINFO, Scopus, OT Seeker, PEDro, ETHOS, Web of Science, and Open Grey were searched for appropriate randomized controlled trials (RCTs). Included papers were assessed for risk of bias, and evidence was graded using the GRADE approach. The protocol was published on PROSPERO (anonymized). RESULTS Ten RCTs met the inclusion/exclusion criteria. There was conflicting evidence from seven RCTs for the efficacy of SDT for chronic low back pain (CLBP). There was very low-quality evidence from two studies supporting the efficacy of SDT for phantom limb pain (PLP). There was very low-quality evidence from one RCT for the efficacy of SDT for Fibromyalgia. No adverse effects of SDT were identified. CONCLUSIONS SDT has been delivered in multiple forms in the literature. SDT does not appear to be associated with any adverse effects and shows potential regarding its clinical efficacy. However, there is a lack of high-quality evidence upon which to make any firm clinical recommendations.

The analysis of time series data is common in nutrition and metabolism research for quantifying the physiological responses to various stimuli. The reduction of many data from a time series into a summary statistic(s) can help quantify and communicate the overall response in a more straightforward way and in line with a specific hypothesis. Nevertheless, many summary statistics have been selected by various researchers, and some approaches are still complex. The time-intensive nature of such calculations can be a burden for especially large data sets and may, therefore, introduce computational errors, which are difficult to recognize and correct. In this short commentary, the authors introduce a newly developed tool that automates many of the processes commonly used by researchers for discrete time series analysis, with particular emphasis on how the tool may be implemented within nutrition and exercise science research.

To evaluate the magnitude of the difference in VO2peak between patients with Chronic Fatigue Syndrome/ Myalgic Encephalomyelitis (CFS/ME) and apparently healthy controls, 7 databases (Cochrane, PubMed, PsycINFO, Web of Knowledge, Embase, Scopus, Medline) were searched for articles published up to March 2018. Search terms included “chronic fatigue syndrom*”AND (“peak” OR “maxim*” OR “max”) AND (“oxygen uptake” OR “oxygen consumption” OR “VO2peak” or “VO2max”. Eligibility criteria were adults>18 y with clinically diagnosed CFS/ME, with VO2peak measured in a maximal test and compared against an apparently healthy control group. The methodological quality of included studies was assessed using a modified Systematic Appraisal of Quality for Observational Research critical appraisal framework. A random effects meta-analysis was conducted on 32 cross-sectional studies (effects). Pooled mean VO2peak was 5.2 (95% CI: 3.8–6.6) ml.kg−1min−1 lower in CFS/ME patients vs. healthy controls. Between-study variability (Tau) was 3.4 (1.5–4.5) ml.kg−1min−1 indicating substantial heterogeneity. The 95% prediction interval was −1.9 to 12.2 ml.kg−1min−1. The probability that the effect in a future study would be>the minimum clinically important difference of 1.1 ml.kg−1min−1 (in favour of controls) was 0.88 – likely to be clinically relevant. Synthesis of the available evidence indicates that CFS/ME patients have a substantially reduced VO2peak compared to controls.

BACKGROUND Gamma irradiation of red blood cells (RBCs) is well recognized to exacerbate storage lesion formation, but the effect of storage after irradiation on in vivo oxygen delivery capacity of transfused RBCs is currently not known. STUDY DESIGN AND METHODS In 24 preterm infants with anemia receiving nonurgent transfusion of irradiated RBCs, we examined cerebral regional tissue oxygenation (crSO2 ) and time spent with peripheral arterial saturation (SpO2 ) less than 88%. Physiologic data were obtained immediately before, immediately after, and 5 days after transfusion. RESULTS We observed linear negative moderate correlations between time since irradiation and the magnitude of change in crSO2 (r = -0.60; 95% CI, -0.81 to -0.27; p = 0.0018) and time spent with SpO2 of less than 88% (r = -0.42; 95% CI, -0.71 to 0.003; p = 0.04) immediately after transfusion. In infants (n = 9) who received fresher RBCs (irradiated

Worldwide prevalence of adult overweight and obesity is a growing public health issue. Adults with overweight/obesity often have chronic musculoskeletal pain. Using a mixed-methods review, we aimed to quantify the effectiveness and explore the appropriateness of weight-loss interventions for this population. Electronic databases were searched for studies published between 01/01/90-01/0716. The review included 14 randomised controlled trials that reported weight and pain outcomes and three qualitative studies that explored perceptions of adults with co-existing overweight/obesity and CMP. The random-effects pooled mean weight-loss was 4.9kg (95%CI:2.9,6.8) greater for intervention vs control. The pooled mean reduction in pain was 7.3/100units (95%CI:4.1,10.5) greater for intervention vs control. Study heterogeneity was substantial for weight loss (I2=95%, tau={plusmn}3.5kg) and pain change (I2=67%, tau={plusmn}4.1%). Meta-regression slopes for the predictors of study quality, mean age and baseline mean weight on mean study weight reduction were shallow and not statistically significant (P>0.05). The meta-regression slope between mean pain reduction and mean weight lost was shallow, and not statistically significant, -0.09kg per unit pain score change (95%CI:-0.21,0.40,p=0.54). Meta-synthesis of qualitative findings resulted in two synthesized findings; the importance of healthcare professionals understanding the effects of pain on ability to control weight, and developing management/education programmes that address comorbidity.

Background Cardiorespiratory fitness is a strong predictor of all-cause mortality. Physical activity of at least moderate intensity can improve cardiorespiratory fitness. Workplaces may provide a relatively controlled setting in which to improve cardiorespiratory fitness through physical activity. Limited work has been conducted to quantify the impact of delivering physical activity in the workplace on cardiorespiratory fitness.Objective The objective of this systematic review was to quantify the effects of workplace physical activity interventions on peak oxygen consumption (VO2peak) and explore study and participant characteristics as putative moderators.Methods Seven databases were searched up to September 2018. Search terms included "workplace", "physical activity" and "intervention". Inclusion criteria were controlled trials where physical activity of at least moderate intensity was delivered in the workplace and compared to controls or non-active comparators; and cardiorespiratory fitness measured by actual or predicted VO2peak. Risk of bias was assessed using the PEDro scale. A random-effects meta-analysis was conducted with between-study variation quantified and then explored for putative predictors with a meta-regression. Pooled estimate uncertainty was expressed as 90% confidence intervals (CIs) and assessed against our threshold value for clinical relevance of 1 mL.kg(-1).min(-1).Results The final dataset consisted of 25 estimates of VO2peak from 12 trials. The pooled mean differences between intervention and control arms was a beneficial improvement of 2.7 mL.kg(-1).min(-1) (90% CI 1.6-3.8). The 95% prediction interval ranged from a reduction in VO2peak of -1.1 to an improvement of 6.5 mL.kg(-1).min(-1). Between-study heterogeneity (tau au) was +/- 1.6 mL.kg(-1).min(-1). The meta-regression showed longer interventions (3.2 mL.kg(-1).min(-1); 90% CI 1.6-3.8) to have an additive effect and studies with a low risk of bias (-2.5 mL.kg-1.min-1; 90% CI -4.0 to -1.0), and participants of greater baseline VO2peak (-1.6 mL.kg(-1).min(-1); 90% CI -3.6 to 0.4), and age (-1.4 mL.kg(-1).min(-1); 90% CI -3.2 to 0.3) having a lesser effect. Participant sex (percentage female) had an additive effect on VO2peak (0.4 mL.kg(-1).min(-1); 90% CI -1.6 to 2.4).Conclusions Workplace-based physical activity interventions consisting of at least moderate-intensity activity improve cardiorespiratory fitness. At the present time, we surmise that no single group of employees (e.g. older employees or less fit individuals) can be definitively identified as standing to benefit more from workplace physical activity interventions than others. This demonstrates the potential utility of workplace physical activity interventions for improving cardiorespiratory fitness in a broad range of healthy employees. usc Refereed/Peer-reviewed

New findings What is the topic for this review? We discuss the dichotomization of continuous-level physiological measurements into 'responders' and 'non-responders' when interventions/treatments are examined in robust parallel-group studies. What advances does it highlight? Sample responder counts are biased by pre-to-post within-subject variability. Sample differences in counts may be explained wholly by differences in mean response, even without individual response heterogeneity and even if test-retest measurement error informs the choice of response threshold. A less biased and more informative approach uses the SD of individual responses to estimate the chance a new person from the population of interest will be a responder. Abstract As a follow-up to our 2015 review, we cover more issues on the topic of 'response heterogeneity', which we define as clinically important individual differences in the physiological responses to the same treatment/intervention that cannot be attributed to random within-subject variability. We highlight various pitfalls with the common practice of counting the number of 'responders', 'non-responders' and 'adverse responders' in samples that have been given certain treatments or interventions for research purposes. We focus on the classical parallel-group randomized controlled trial and assume typical good practice in trial design. We show that sample responder counts are biased because individuals differ in terms of pre-to-post within-subject random variability in the study outcome(s) and not necessarily treatment response. Ironically, sample differences in responder counts may be explained wholly by sample differences in mean response, even if there is no response heterogeneity at all. Sample comparisons of responder counts also have relatively low statistical precision. These problems do not depend on how the response threshold has been selected, e.g. on the basis of a measurement error statistic, and are not rectified fully by the use of confidence intervals for individual responses in the sample. The dichotomization of individual responses in a research sample is fraught with pitfalls. Less biased approaches for estimating the proportion of responders in a population of interest are now available. Importantly, these approaches are based on the SD for true individual responses, directly incorporating information from the control group.

Background The fat mass and obesity-associated gene (FTO) rs9939609 A-allele has been associated with obesity risk. Although the exact mechanisms involved remain unknown, the FTO rs9939609 A-allele has been associated with an impaired postprandial suppression of appetite. Objectives To explore the influence of FTO rs9939609 genotype on fasting and postprandial appetite-related hormones and perceived appetite in a heterogeneous sample of men and women. Design 112 healthy men and women aged 18-50-years-old completed three laboratory visits for the assessment of FTO rs9939609 genotype, body composition, aerobic fitness, resting metabolic rate, visceral adipose tissue, liver fat, fasting leptin, and fasting and postprandial acylated ghrelin, total PYY, insulin, glucose and perceived appetite. Participants wore accelerometers for seven consecutive days for the assessment of physical activity and sedentary behaviour. Multivariable general linear models quantified differences between FTO rs9939609 groups for fasting and postprandial appetite outcomes, with and without the addition of a priori selected physiological and behavioural covariates. Sex-specific univariable Pearson's correlation coefficients were quantified between the appetite-related outcomes and individual characteristics. Results 95% confidence intervals for mean differences between FTO rs9939609 groups overlapped zero in unadjusted and adjusted general linear models for all fasting (P ≥ 0.28) and postprandial (P ≥ 0.19) appetite-related outcomes. Eta2 values for explained variance attributable to FTO rs9939609 were Conclusions Associations between the FTO rs9939609 genotype and fasting or postprandial appetite-related outcomes were weak in healthy men and women.

REVIEW QUESTION/OBJECTIVE: The objective of this mixed methods review is to develop an aggregated synthesis of qualitative and quantitative data on weight-loss interventions for overweight/obese adults with chronic musculoskeletal pain in an attempt to derive conclusions and recommendations useful for clinical practice and policy decision making.The objective of the quantitative component of this review is to quantify the effectiveness of weight-loss interventions on weight, pain and physical and/or psychosocial function in overweight/obese adults with chronic musculoskeletal pain.The objectives of the qualitative component of this review are to explore the perceptions and experiences of overweight/obese adults with chronic musculoskeletal pain of the link between their weight and pain, and the effectiveness and appropriateness of weight-loss interventions and sustainability of weight-loss efforts.

The measurement of relative physiological stress during training is important because this is the stimulus for the long-term adaptive response. Measurements of perceived exertion (RPE) have been reported to correlate with the heart rate during field-based training sessions. Nevertheless, there are few studies on how well RPE tracks with the heart rate over repeated training sessions in elite soccer players. Therefore, we aimed to quantify the within-participant correlations between variability in session-RPE (sRPE) and the heart rate in elite male soccer players, and to determine whether the playing position moderated these correlations. The field-based training of four central defenders, four wide defenders, six central midfielders, two wide midfielders and three attackers from an elite English Premier League squad were monitored over an entire in-season competitive period, giving a total of 1010 individual training sessions for study. Correlations between session-RPE and heart rates were quantified using a within-participant model. The correlation between changes in sRPE and heart rates was r = 0.75 (95% CI: 0.71-0.78). This correlation remained high across the various player positions (wide-defender, r = 0.81; central-defender, r = 0.74; wide midfielder, r = 0.70; central midfielder, r = 0.70; attacker, r = 0.84; P

Background: Two-point discrimination (TPD) is an assessment of tactile acuity. People with multiple sclerosis (MS) can have reduced foot sole tactile acuity, which has been linked to impaired balance. Objective: To quantify the test–retest reliability of TPD on the sole of the foot in people with MS. Approach: 41 participants (32 females), with mean (SD) age of 60 (9) years, and Expanded Disability Status Scale of Main results: Systematic learning effects were evident. The within-subjects SD at the metatarsal and the heel was 6.7 mm (5.5–8.6) and 8.3 mm (6.7–10.8), and the LOAs were 18.6 mm (15.2–24.) and 23.7 mm (18.7–30.1), respectively. ICCs for metatarsal and heel was 0.87 (0.76–0.93) and 0.90 (0.80–0.95), respectively, but these were likely inflated by sample heterogeneity. Significance: In people with MS, TPD on the sole of the foot has an adequate test–retest reliability for research purposes, but there is substantial measurement variability for individual patients.

Introduction People with Chronic Obstructive Pulmonary Disease (COPD) are four times more likely to fall than healthy peers, leading to increased morbidity, mortality and healthcare costs. Balance impairment in COPD has been linked to falls but the degree of balance dysfunction and mechanisms underlying such impairment in COPD are unknown. We conducted a systematic review to establish 1. the extent to which balance is impaired in COPD compared to healthy controls and 2. to determine the clinical factors that may contribute to balance impairment in COPD. Methods We undertook a search of five electronic databases, of studies comparing individuals with COPD and healthy controls that measured static or dynamic balance. Meta-analysis was possible on three clinical balance measures which were assessed in five or more studies. A meta-regression using difference in% predicted FEV1 as an indicator of disease severity was conducted. Finally, we performed a meta-analysis on correlation data of balance impairment and reduced quadriceps strength; the only associated factor assessed in five studies. A narrative summary was conducted when meta-analysis was not possible. Results 3904 records were identified after de-duplication. 75 full texts were screened, with 23 studies included in the quantitative synthesis. People with COPD performed worse than healthy controls on Timed Up and Go (p≤0.005, 95% CI 0.964 to 2.257 s), Single Leg Stance (p=0.001, 95% CI −2.983 to −0.775 s) and Berg Balance Scale (p≤0.005, 95% CI −2.238 to −1.021), with large effect sizes (standardised difference in means=1.746, 1.879 and 1.630 respectively). There was no effect of disease severity. There was a weak to moderate association between clinical balance outcomes and reduced quadriceps strength (r=0.370, p≤0.005). Individual study results suggest balance impairment is associated with reduced physical activity and exercise capacity. Conclusions People with COPD have large deficits in their balance compared to healthy controls and this appears related to reduced quadriceps strength, physical activity and exercise capacity. These factors are modifiable with exercise interventions and the findings of this review can be used to inform tailored interventions for balance impairment and supports that assessment and management of balance should be part of COPD care guidelines.

An important question for researchers and practitioners is whether an individual’s risk of injury increases if they make prior changes to their training load.1 In this field of research, ‘load’ typically refers to in-training distances covered, speed and accelerations.1 Attention has generally focused on whether a person’s acute (eg, 7 day) increase in load, normalised to that person’s prior ‘baseline’ of chronic (eg, 28 day) load, predicts injury.1 To obtain this normalised predictor, acute load is typically divided by chronic load to provide the acute-to-chronic workload ratio (ACWR).1 Fundamentally, simple ratios (Y/X) are formulated to ‘ control for ’ a denominator variable (eg, preceding chronic load) that is perceived to have an important biological influence on the numerator variable (eg, acute load).2 Within this notion of ‘ control for ’,3 it is generally posited that the denominator is a ‘nuisance’ variable that is associated with the numerator of interest.2 Logically, a simple ratio index provides meaningful relative measures for clinical and prognostic purposes only if (1) there is a ‘true’ and ‘proportional’ association between numerator and denominator in the first place, and (2) the ratio normalises for the denominator in a consistent manner for all individuals in the measurement range.2 We have demonstrated recently that the typical practice in the current literature1 of including, …

Purpose: \ud Acute exercise transiently suppresses appetite, which coincides with alterations in appetite-regulatory hormone concentrations. Individual variability in these responses is suspected, but replicated trials are needed to quantify them robustly. We examined the reproducibility of appetite and appetite-regulatory hormone responses to acute exercise and quantified the individual differences in responses.\ud \ud Methods: \ud Fifteen healthy, recreationally active men completed two control (60-min resting) and two exercise (60-min fasted treadmill running at 70% peak oxygen uptake) conditions in randomized sequences. Perceived appetite and circulating concentrations of acylated ghrelin and total peptide YY (PYY) were measured immediately before and after the interventions. Interindividual differences were explored by correlating the two sets of response differences between exercise and control conditions. Within-participant covariate-adjusted linear mixed models were used to quantify participant–condition interactions.\ud \ud Results: \ud Compared with control, exercise suppressed mean acylated ghrelin concentrations and appetite perceptions (all ES = 0.62–1.47, P < 0.001) and elevated total PYY concentrations (ES = 1.49, P < 0.001). For all variables, the standard deviation of the change scores was substantially greater in the exercise versus control conditions. Moderate-to-large positive correlations were observed between the two sets of control-adjusted exercise responses for all variables (r = 0.54–0.82, P ≤ 0.036). After adjusting for baseline measurements, participant–condition interactions were present for all variables (P ≤ 0.053).\ud \ud Conclusions: \ud Our replicated crossover study allowed, for the first time, the interaction between participant and acute exercise response in appetite parameters to be quantified. Even after adjustment for individual baseline measurements, participants demonstrated individual differences in perceived appetite and hormone responses to acute exercise bouts beyond any random within-subject variability over time.

Longitudinal observational study.To investigate the association between the duration of pain at baseline and the clinical outcomes of patients with low back pain (LBP) enrolled on the North East of England Regional Back Pain and Radicular Pain Pathway (NERBPP).The NERBPP is a clinical pathway based upon National Institute for Health and Care Excellence (NICE) guidelines (2009) for LBP of1-year duration. Recent changes to NICE guidelines (2016) advocate the same management for all LBP patients regardless of pain duration.Patients with LBP referred onto the NERBPP by their General Practitioner between May 2015 and January 2017 were included. Data from 667 patients, who provided pre- and post data for pain (Numerical rating scale), function (Oswestry Disability Index), quality-of-life (EuroQol five-dimension, five-level questionnaire), anxiety (the Generalized Anxiety Disorder Screener), and depression (the Patient Health Questionnaire), were analyzed using a series of covariate-adjusted models. Patients were categorized into four groups based upon baseline pain duration:3 months, ≥3 to6 months, ≥6 months to12 months, ≥12 months.Each group showed improved outcomes greater than the minimal clinically important difference (MCID) for each measure as defined in NICE guidelines (2016). There was a trend toward better outcomes for those with shorter pain durations. The magnitude of the differences between the groups, in most instances, was below the MCID. For example, mean improvement in function for those with baseline pain duration3 months was 20 points and 12 points for those of pain duration ≥12 months, both above the MCID of ≥10.Patients with different durations of LBP at baseline improved on the NERBPP, supporting the recent modification to NICE guidelines. However, those with shorter durations of pain may have superior outcomes in the short term, suggesting added benefit in getting patients onto the pathway in the early stages of LBP.3.

Purpose:To quantify the relationship between daily training load and a range of potential measures of fatigue in elite soccer players during an in-season competitive phase (17 d).Methods:Total high-intensity-running (THIR) distance, perceived ratings of wellness (fatigue, muscle soreness, sleep quality), countermovement-jump height (CMJ), postexercise heart-rate recovery (HRR), and heart-rate variability (Ln rMSSD) were analyzed during an in-season competitive period (17 d). General linear models were used to evaluate the influence of daily fluctuation in THIR distance on potential fatigue variables.Results:Fluctuations in fatigue (r = −.51, large, P < .001), Ln rMSSD (r = −.24, small, P = .04), and CMJ (r = .23, small, P = .04) were significantly correlated with fluctuations in THIR distance. Correlations between variability in muscle soreness, sleep quality, and HRR and THIR distance were negligible and not statistically significant.Conclusions:Perceived ratings of fatigue and Ln rMSSD were sensitive to daily fluctuations in THIR distance in a sample of elite soccer players. Therefore, these particular markers show promise as simple, noninvasive assessments of fatigue status in elite soccer players during a short in-season competitive phase.

Purpose: The aim of the current study was to identify the external-training-load markers that are most influential on session rating of perceived exertion (RPE) of training load (RPE-TL) during elite soccer training. Methods: Twenty-two elite players competing in the English Premier League were monitored. Training-load data (RPE and 10-Hz GPS integrated with a 100-Hz accelerometer) were collected during 1892 individual training sessions over an entire in-season competitive period. Expert knowledge and a collinearity r < .5 were used initially to select the external training variables for the final analysis. A multivariateadjusted within-subjects model was employed to quantify the correlations of RPE and RPE-TL (RPE × duration) with various measures of external training intensity and training load. Results: Total high-speed-running (HSR; >14.4 km/h) distance and number of impacts and accelerations >3 m/s2 remained in the final multivariate model (P < .001). The adjusted correlations with RPE were r = .14, r = .09, and r = .25 for HSR, impacts, and accelerations, respectively. For RPE-TL, the correlations were r = .11, r = .45, and r = .37, respectively. Conclusions: The external-load measures that were found to be moderately predictive of RPE-TL in soccer training were HSR distance and the number of impacts and accelerations. These findings provide new evidence to support the use of RPE-TL as a global measure of training load in elite soccer. Furthermore, understanding the influence of characteristics affecting RPE-TL may help coaches and practitioners enhance training prescription and athlete monitoring.

Gamma irradiation of red blood cells (RBCs) is well recognized to exacerbate storage lesion formation, but the effect of storage after irradiation on in vivo oxygen delivery capacity of transfused RBCs is currently not known.In 24 preterm infants with anemia receiving nonurgent transfusion of irradiated RBCs, we examined cerebral regional tissue oxygenation (crSOWe observed linear negative moderate correlations between time since irradiation and the magnitude of change in crSOOur findings indicate that storage after gamma irradiation may have a detrimental effect on the oxygen delivery capacity of RBCs given to anemic preterm infants.

The monitoring of training load is important to ensure athletes are adapting optimally to a training stimulus. Before quantification of training load can take place, coaches must be confident that the tools available are accurate. We aimed to quantify the within-participant correlation between the session rating of perceived exertion (s-RPE) and summated heart rate zone (sHRz) methods of monitoring internal training load. Training load (s-RPE and heart rate) data were collected for rugby, soccer and field hockey field-based training sessions over a 14-week in-season period. A total of 397 sessions were monitored (rugby n=170, soccer n=114 and field hockey n=113). Within-subject correlations between s-RPE and sHRz were quantified for each sport using a general linear model. Large correlations between s-RPE and the sHRz method were found for rugby (r=0.68; 95% CI 0.59–0.75) and field hockey (r=0.60; 95% CI 0.47–0.71) with a very large correlation found for soccer (r=0.72; 95% CI 0.62–0.80). No significant differences were found between the correlations for each sport. The very large and large correlations found between s-RPE and the sHRz methods support the use of s-RPE in quantifying internal training load in youth sport.

Objective To quantify the influence of baseline pain levels on weight change at one-year follow-up in patients attending a National Health Service specialist weight management programme. Methods We compared one-year follow-up weight (body mass) change between patient sub-groups of none-to-mild, moderate, and severe pain at baseline. A mean sub-group difference in weight change of ≥5kg was considered clinically relevant. Results Of the 141 complete cases, n = 43 (30.5%) reported none-to-mild pain, n = 44 (31.2%) reported moderate pain, and n = 54 (38.3%) reported severe pain. Covariate-adjusted mean weight loss (95%CI) was similar for those with none-to-mild (8.1kg (4.2 to 12.0kg)) and moderate pain (8.3kg (4.9 to 11.7kg). The mean weight loss of 3.0kg (-0.4 to 6.4kg) for the severe pain group was 5.1kg (-0.6 to 10.7, p = 0.08) lower than the none-to-mild pain group and 5.3kg (0.4 to 10.2kg, p = 0.03) lower than the moderate pain group. Conclusions Patients with severe pain upon entry to a specialist weight management service in England achieve a smaller mean weight loss at one-year follow-up than those with none-to-moderate pain. The magnitude of the difference in mean weight loss was clinically relevant, highlighting the importance of addressing severe persistent pain in obese patients undertaking weight management programmes.

Chronic musculoskeletal pain (CMP) is an urgent global public health concern. Pain neuroscience education (PNE) is an intervention used in the management of CMP aiming to reconceptualize an individual's understanding of their pain as less threatening. This mixed-methods review undertook a segregated synthesis of quantitative and qualitative studies to investigate the clinical effectiveness, and patients’ experience of, PNE for people with CMP. Electronic databases were searched for studies published between January 1, 2002, and June 14, 2018. Twelve randomized, controlled trials (n = 755 participants) that reported pain, disability, and psychosocial outcomes and 4 qualitative studies (n = 50 participants) that explored patients experience of PNE were included. The meta-analyzed pooled treatment effects for PNE versus control had low clinical relevance in the short term for pain (−5.91/100; 95% confidence interval [CI], −13.75 to 1.93) and disability (−4.09/100; 95% CI, −7.72 to −.45) and in the medium term for pain (−6.27/100; 95% CI, −18.97 to 6.44) and disability (−8.14/100; 95% CI, −15.60 to −.68). The treatment effect of PNE for kinesiophobia was clinically relevant in the short term (–13.55/100; 95% CI, –25.89 to –1.21) and for pain catastrophizing in the medium term (–5.26/52; 95% CI, –10.59 to .08). A metasynthesis of 23 qualitative findings resulted in the identification of 2 synthesized findings that identified several key components important for enhancing the patient experience of PNE, such as allowing the patient to tell their own story. These components can enhance pain reconceptualization, which seems to be an important process to facilitate patients’ ability to cope with their condition. The protocol was published on PROSPERO (CRD42017068436). Perspective: We outline the effectiveness of PNE for the management of pain, disability, and psychosocial outcomes in adults with CMP. Key components that can enhance the patient experience of PNE, such as allowing the patient to tell their own story, are also presented. These components may enhance pain reconceptualization.

In keeping with this review-series theme, we question whether the morning surge in blood pressure (MSBP) is a benign response to the physiological challenges during the first 3 h after waking, or is it clinically important? Therefore, we scrutinise the circadian-related mechanisms, the measurement methods and the prognostic value of the MSBP. The MSBP is relatively small (2 mmHg) under constant routine conditions. Nevertheless, the blood pressure response to exercise can be 8-14 mm Hg greater in the morning vs. afternoon, even when prior sleep is controlled. Systematic bias between MSBP methods can be10 mmHg. The "sleep-trough" method provides the largest MSBP (≈25 mmHg), but the sensitivity of MSBP to a treatment/intervention depends largely on its repeatability. The repeatability standard deviation (SD) for most MSBP methods is ≈8 mm Hg. While the magnitude of this SD precludes the use of MSBP for diagnostic decisions on individual patients, sample sizes for future intervention studies may be feasible, depending on the minimal clinically important difference in MSBP. This difference is somewhat unclear given that a large MSBP has recently been reported to predict a reduced, rather than a higher, risk of cardiovascular disease, although this particular study has been criticised. The MSBP is also naturally correlated to changes in physical activity and nocturnal "dipping" status. Therefore, it is important to account for these potential confounders of the MSBP, so that more precise knowledge about its clinical significance is gained, thereby providing a sound rationale for physiological investigation and translational research.

A melatonin-mediated reduction in body temperature could be useful as a "pre-cooling" intervention for athletes, as long as the melatonin dose is optimised so that substantial soporific effects are not induced. However, the melatonin-temperature dose-response relationship is unclear in humans. Individual studies have involved small samples of different sexes and temperature measurement sites. Therefore, we meta-analysed the effects of exogenous melatonin on body core temperature to quantify the dose-response relationship and to explore the influence of moderating variables such as sex and measurement site. Following a literature search, we meta-analysed 30 data-sets involving 193 participants and 405 ingestions of melatonin. The outcome was the mean difference (95 % confidence limits) in core temperature between the melatonin and placebo-controlled conditions in each study, weighted by the reciprocal of each standard error of the difference. The mean (95 % confidence interval) pooled reduction in core temperature was found to be 0.21 °C (0.18-0.24 °C). The dose-response relationship was found to be logarithmic (P0.0001). Doses of 0-5 mg reduced temperature by ~0.00-0.22 °C. Any further reductions in temperature were negligible with doses5 mg. The pooled mean reduction was 0.13 °C (0.05-0.20 °C) for oral temperature vs 0.26 °C (0.20-0.32 °C) for tympanic and 0.22 °C (0.19-0.25 °C) for rectal temperature. In conclusion, our meta-regression revealed a logarithmic dose-response relationship between melatonin and its temperature lowering effects. A 5-mg dose of melatonin lowered core temperature by ~0.2 °C. Higher doses do not substantially increase this hypothermic effect and may induce greater soporific effects.

We compared measurements of high-intensity activity during field-based training sessions in elite soccer players of different playing positions. Agreement was appraised between measurements of running speed alone and predicted metabolic power derived from a combination of running speed and acceleration. Data was collected during a 10-week phase of the competitive season from 26 English Premier League outfield players using global positioning system technology. High-intensity activity was estimated using the total distance covered at speeds14.4 km · h⁻¹ (TS) and the equivalent metabolic power threshold of20 W · kg⁻¹ (TP), respectively. We selected 0.2 as the -minimally important standardised difference between methods. Mean training session TS was 478±300 m vs. 727±338 m for TP (p0.001). This difference was greater for central defenders (~ 85%) vs. wide defenders and attackers (~ 60%) (p0.05). The difference between methods also decreased as the proportion of high-intensity distance within a training session increased (R2=0.43; p0.001). We conclude that the high-intensity demands of soccer training are underestimated by traditional measurements of running speed alone, especially in training sessions or playing positions associated with less high-intensity activity. Estimations of metabolic power better inform the coach as to the true demands of a training session.

Aim The ability to maintain arterial blood pressure when faced with a postural challenge has implications for the occurrence of syncope and falls. It has been suggested that posture-induced declines in the mechanical component of the baroreflex response drive reductions in cardiovagal baroreflex sensitivity associated with postural stress. However, these conclusions are largely based upon spontaneous methods of baroreflex assessment, the accuracy of which has been questioned. Therefore, the aim was to engage a partially open-loop approach to explore the influence of posture on the mechanical and neural components of the baroreflex. Methods In nine healthy participants, we measured continuous blood pressure, heart rate, RR interval and carotid artery diameter during supine and standing postures. The modified Oxford method was used to quantify baroreflex sensitivity. Results In response to falling pressures, baroreflex sensitivity was similar between postures (P = 0.798). In response to rising pressures, there was an attenuated (P = 0.042) baroreflex sensitivity (mean ± SE) in the standing position (−0.70 ± 0.11 beats min−1 mmHg−1) compared with supine (−0.83 ± 0.06 beats min−1 mmHg−1). This was explained by a diminished (P = 0.016) neural component whilst standing (−30.17 ± 4.16 beats min−1 mm−1) compared with supine (−38.23 ± 3.31 beats min−1 mm−1). These effects were consistent when baroreflex sensitivity was determined using RR interval. Conclusion Cardiovagal baroreflex sensitivity in response to rising pressures is reduced in young individuals during postural stress. Our data suggest that the mechanical component is unaffected by standing, and the reduction in baroreflex sensitivity is driven by the neural component.