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The idea that increasing physical activity directly adds to total energy expenditure in humans (additive model) has been challenged by the energy constrained hypothesis (constrained model). This model proposes that increased physical activity decreases other components of metabolism to constrain total energy expenditure. There is a logical evolutionary argument for trade-offs in metabolism but, to date, evidence supporting constraint is subject to several limitations including cross-sectional and correlational studies with potential methodological issues from extreme differences in body size/composition and lifestyle, potential statistical issues such as regression dilution and spurious correlations, and conclusions drawn from deductive inference rather than direct observation of compensation. Addressing these limitations in future studies, ideally randomized controlled trials, should improve the accuracy of models of human energy expenditure. The available evidence indicates that in many scenarios, the effect of increasing physical activity on total energy expenditure will be mostly additive – although some energy appears to ‘go missing’ and is currently unaccounted for. The degree of energy balance could moderate this effect even further.

La guía CONSORT (CONsolidated Standards Of Reporting Trials)de 2010 (http://www.consort-statement.org/consort-2010) fuedesarrollada para mejorar el informe de ensayos clínicoscontrolados aleatorios de grupos paralelos, por lo que elcumplimiento de los estándares establecidos se puede demostrarmediante la cumplimentación de la lista de chequeo CONSORT20101. Las principales revistas médicas han respaldado estainiciativa, que sin duda ha mejorado la realización y el informe deresultados de la investigación clínica y sanitaria. La investigaciónen el campo de la nutrición deportiva y el metabolismo delejercicio se beneficiará de estándares similares, pero comúnmenteutiliza diseños de investigación diferentes a los ensayos clínicos degrupos paralelos, como los experimentos cruzados.Se ha publicado recientemente una ampliación de CONSORT queaborda ensayos cruzados aleatorios2, con una lista de verificaciónrevisada que se centra en cuestiones de primera relevancia paraensayos clínicos que abordan tratamientos médicos o deasistencia médica. Sin embargo, estas cuestiones específicas de losensayos clínicos, pueden tener una relevancia diferente, cuando seconsideran en relación con los experimentos mecanicistas,estrictamente controlados, realizados en laboratorio, que sonhabituales en la ciencia del ejercicio. Por ejemplo, los diseñoscruzados pueden implicar efectos de orden entre evaluaciones; enlos ensayos clínicos, esto suele ocurrir con mayor frecuenciadebido al tratamiento o la intervención en sí, lo que requiere unintervalo de lavado suficiente, antes de repetir las evaluaciones.Por el contrario, la tendencia en la investigación sobre nutricióndeportiva, se relaciona comúnmente con la evaluación en símisma, que a menudo, tiende a ser más invasiva o exigente para elparticipante, que una instantánea sobre su estado de salud. Dehecho, las pruebas físicas de rendimiento humano sonparticularmente propensas a efectos de aprendizaje o fatiga eincluso algunas adaptaciones físicas pueden persistir durantesemanas o meses después del primer test. Por ejemplo, eldenominado “efecto de intentos repetidos”, que describe cómo unasola exposición a un ejercicio físico desacostumbrado que producedaño muscular puede inducir una profunda y duradera protecciónante ejercicios similares en el futuro3,4. Los participantes enensayos de ejercicio también pueden ser atletas de élite, cuyosniveles habituales de actividad física (y dieta) pueden mostrarvariaciones profundas a lo largo del tiempo (es decir,periodización), lo que complica aún más la interpretación deestudios longitudinales.La lista de chequeo PRESENT (Proper Reporting of Evidence inSport & Exercise Nutrition Trials) 2020 (Ver Anexo), por tanto, seha adaptado de la guía CONSORT para abordar específicamente lacombinación única de desafíos y oportunidades que enfrentan losinvestigadores dentro de los amplios campos de la nutricióndeportiva y el metabolismo del ejercicio. El presente documentocomplementa y desarrolla la lista de verificación CONSORT alponer énfasis y proveer ejemplos comunes o de mayor relevanciapara la investigación en esta área temática. La lista decomprobación PRESENT 2020 se diseñó 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; debería permitir a los investigadoresdeterminar rápidamente si toda la información relevante estáincluida en su manuscrito. Por supuesto, es posible cumplir contodos los factores en la lista de verificación 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 consideración ydiscusión de los factores identificados en la lista de chequeodebería mejorar la comunicación de los resultados de lainvestigación relacionada con el ejercicio y la nutrición, en elfuturo inmediato, y tiene el potencial de mejorar el diseño y larealización de ensayos a largo plazo.

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In lean individuals, acute aerobic exercise is reported to transiently suppress sensations of appetite, suppress blood concentrations of acylated ghrelin (AG), and increase glucagon-like peptide-1 (GLP-1) and peptide-YY (PYY). Findings in overweight/obese individuals have yet to be synthesised. In this systematic review and meta-analysis, we quantified the effects that acute exercise has on AG and total PYY and GLP-1 in overweight/obese individuals. The potential for body mass index (BMI) to act as a moderator for AG was also explored. Six published studies (73 participants, 78% male, mean BMI: 30.6 kg·m−2) met the inclusion criteria. Standardised mean differences (SMDs) and standard errors were extracted for AG and total PYY and GLP-1 concentrations in control and exercise trials and synthesised using a random effects meta-analysis model. BMI was the predictor in metaregression for AG. Exercise moderately suppressed AG area-under-the-curve concentrations (pooled SMD: −0.34, 95% CI: −0.53 to −0.15). The magnitude of this reduction was greater for higher mean BMIs (pooled metaregression slope: −0.04 SMD/kg·m−2 (95% CI: −0.07 to 0.00)). Trivial SMDs were obtained for total PYY (0.10, 95% CI: −0.13 to 0.31) and GLP-1 (−0.03, 95% CI: −0.18 to 0.13). This indicates that exercise in overweight/obese individuals moderately alters AG in a direction that could be associated with decreased hunger and energy intake. This trial is registered with PROSPERO: CRD42014006265.

A post-menopausal hot flush consists of profuse physiological elevations in cutaneous vasodilatation and sweating that are accompanied by reduced brain blood flow. These responses can be used to objectively quantify hot flush severity. The impact of an exercise training intervention on the physiological responses occurring during a hot flush is currently unknown. In a preference-controlled trial involving 21 post-menopausal women, 16 weeks of supervised moderate intensity exercise training was found to improve cardiorespiratory fitness and attenuate cutaneous vasodilatation, sweating and the reductions in cerebral blood flow during a hot flush. It is concluded that the improvements in fitness that are mediated by 16 weeks of exercise training reduce the severity of physiological symptoms that occur during a post-menopausal hot flush. A hot flush is characterised by feelings of intense heat, profuse elevations in cutaneous vasodilatation and sweating, and reduced brain blood flow. Exercise training reduces self-reported hot flush severity, but underpinning physiological data are lacking. We hypothesised that exercise training attenuates the changes in cutaneous vasodilatation, sweat rate and cerebral blood flow during a hot flush. In a preference trial, 18 symptomatic post-menopausal women underwent a passive heat stress to induce hot flushes at baseline and follow-up. Fourteen participants opted for a 16 week moderate intensity supervised exercise intervention, while seven participants opted for control. Sweat rate, cutaneous vasodilatation, blood pressure, heart rate and middle cerebral artery velocity (MCAv) were measured during the hot flushes. Data were binned into eight equal segments, each representing 12.5% of hot flush duration. Weekly self-reported frequency and severity of hot flushes were also recorded at baseline and follow-up. Following training, mean hot flush sweat rate decreased by 0.04 mg cm(2) min(-1) at the chest (95% confidence interval 0.02-0.06, P = 0.01) and by 0.03 mg cm(2) min(-1) (0.02-0.05, P = 0.03) at the forearm, compared with negligible changes in control. Training also mediated reductions in cutaneous vasodilatation by 9% (6-12%) at the chest and by 7% (4-9%) at forearm (P ≤ 0.05). Training attenuated hot flush MCAv by 3.4 cm s(-1) (0.7-5.1 cm s(-1) , P = 0.04) compared with negligible changes in control. Exercise training reduced the self-reported severity of hot flushes by 109 arbitrary units (80-121, P0.001). These data indicate that exercise training leads to parallel reductions in hot flush severity and within-flush changes in cutaneous vasodilatation, sweating and cerebral blood flow.

BAILEY, T. G., H JONES, W. GREGSON, G. ATKINSON, N. T. CABLE, and D. H. J. THIJSSEN. Effect of Ischemic Preconditioning on Lactate Accumulation and Running Performance. Med. Set. Sports Exerc., Vol. 44, No. 11, pp. 2084-2089, 2012. Purpose: Repeated bouts of ischemia followed by reperfusion (i.e., ischemic preconditioning (IPC)) protect against damage after a myocardial infarction. Recent observational data indicate that IPC improves exercise performance. However, no previous study has examined potential underlying mechanisms for this effect of IPC. Therefore, we examined the potential of IPC to improve 5-km running time trial performance and reduce lactate accumulation during an incremental exercise test. Methods: In a randomized, crossover study, 13 healthy men performed running exercise, which was preceded by IPC (4 x 5-min 220 mm Hg bilateral leg occlusion) or a control intervention (C) (4 x 5-min 20 mm Hg bilateral leg occlusion). Participants performed a graded maximal treadmill running test, starting with five 3-min submaximal stages (10-14 km.h(-1)), followed by increments of 1 km.h(-1) every 2 min to 16 km.h(-1), followed by an incline of the treadmill of 2% every 2 min. Blood lactate was examined at each 3-min stage. After 45 min of rest in the supine position, subjects then performed a 5-km running time trial. Results: We found similar submaximal gas parameters during running exercise with both interventions. The overall increase in blood lactate during the submaximal stages was 1.07 +/- 0.11 mmol.L-1 lower when exercise was preceded with IPC versus C (P = 0.023). The 5-km running time trial was completed in a time that was 34 s faster after IPC versus C (95% confidence interval, 5-64 s; P = 0.027). Conclusion: IPC improves 5-km time trial performance in healthy male individuals. Moreover, we found that IPC is associated with an attenuated rise in blood lactate concentration at submaximal level during an incremental running test. This could indicate that IPC allows for higher work rates and thus improves time trial performance.

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

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

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

A lack of physical activity in general and among children and youth in particular is a growing concern noticeable in research, campaigns and programs. Being physically inactive is highly related to negative influences on several health related factors such as growing prevalence of obesity, increased risks of cardio-respiratory diseases, prevalence of diabetes, and so on. Poor physical activity participation also threatens development of motor competence and can result in a strong decrease or fade away of participation in the sport and movement culture. Because of limited (spontaneous) movement opportunities among young children however, the fundamental movement skills may be strongly delayed or not fully developed. In addition, a shortage of physical activity can have a pernicious influence on the perception of well-being, the so-called quality of life. In this contribution we emphasize the development of fundamental movement skills among pre-school children because of the limited attention that is been givento this subject in the story of this issue. The age category of preschoolers as well as development of fundamental movement skills are seldom considered in research concerning physical activity. A clustered sample of Flemish pre school children (N= 1208, nboys= 654, ngirls=554) was assessed on their fundamental movement skill development with the MOT 4-6 test (Zimmer & Volkamer, 1987). The test features 18 test items including fine motor movement skill and gross motor movement skill items.The participating pre-school children were between 4 and 6 years of age (M=5.18 years, ± 0.61). Length and weight were measured as anthropometric variables. Data were used to describe the developmental status of fundamental movement skills among Flemish preschoolers. A description of total motor composite on the motor assessment test was provided using quartiles for every half year age category. Non parametric statistics in SPSS 15.0 were used for data analysis. Compared to the amount of pre-school children with a higher motor quotient (6%) than the average, there was a larger amount of pre-school children with a lower motor quotient (34,1%). There was a significant difference in the development of fundamental movement skills between boys (mdn = 91) and girls (mdn = 93) (U = 165 760, pIn agreement with findings of other authors, there was a decrease in the development of fundamental movement skills among pre-school children compared to the normative data for the test. Zimmer, R., & Volkamer, M. (1987). Motoriktest für vier- bis sechsjärige Kinder (manual). Weinheim: Betltztest

Introduction: The efficacy of high-intensity interval training (HIIT) for improving markers of physical fitness and cardiometabolic health is promising. The workplace is one non-laboratory setting where the effectiveness of HIIT could be explored. The aim of this study was to undertake a mixed-methods exploratory pilot trial of a workplace HIIT intervention named Brief Exercise at Work (BE@Work).Methods: Fifty-four healthy employees (mean ± standard deviation [SD] age 46 ± 10 years) from two workplaces in Northeast England were allocated to 8 weeks of thrice-weekly workplace HIIT based on boxing, stair climbing and stepping, comprising 4–7 60 s high-intensity intervals interspersed with 75 s rest (n = 30), or a no-intervention control (n = 24). The primary outcome was the change SD of predicted maximal oxygen consumption (VO2max). Markers of physical fitness, cardiometabolic health and mental well-being were also measured at baseline and follow-up. Participant perceptions of the intervention were explored in post-intervention focus groups (n = 9).Results: Mean (±SD) session attendance was 82% (±15%). Mean peak heart rate across the intervention was 87% of age-predicted maximal heart rate with a within- and between-subject SD of 5.5% and 3.7%, respectively. The SD of changes in predicted VO2max was 6.6 mL·kg−1·min−1 across both groups, which can be used to inform sample size estimations for a future full trial. The control-adjusted mean increase (95% confidence interval) in predicted VO2max was 3.9 (−0.2 to 8.1) mL·kg−1·min−1, corresponding to a Cohen's D of 0.47. We also observed preliminary evidence of small to moderate effects in favour of the intervention group for non-dominant leg extensor muscle power, markers of health-related quality of life, well-being and perceived stress and small to moderate effects in favour of the controls in perceived pain, physical activity and high-density lipoprotein cholesterol. During HIIT, focus group participants reported physiological responses they perceived as unpleasant or tiring (e.g., breathlessness, local muscular fatigue), but also that they felt alert and energised afterwards.Conclusion: The findings of this exploratory pilot trial support the implementation of a definitive randomised controlled trial to quantify the effectiveness of a workplace HIIT intervention.

It is clear that many pre-school children do not meet daily physical activity recommendations, which could hamper the development of fundamental movement skills [FMS]. Therefore, we studied the development of FMS among pre-school children aged four to six years. Pre-school children (n=1208) were assessed on their FMS development with the MOT 4-6. Children's body mass and height were measured. Results showed that a mid group of 704 (59%) children were considered having a normal FMS development. Interesting findings, however, were that only a very small group of 72 (6%) children were classified having stronger developed FMS and a worrying larger group of 422 children (35%) were classified having weaker developed FMS. Obese children showed significant lower FMS development than children categorised as having 'normal weights' (U= 26 259.5, p