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OBJECTIVE: To investigate potential moderating effects of resistance exercise dose components including intensity, volume and frequency, for the management of common tendinopathies. DESIGN: Systematic review with meta-analysis and meta-regressions. DATA SOURCES: Including but not limited to: MEDLINE, CINAHL, SPORTDiscus, ClinicalTrials.gov and ISRCTN Registry. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Randomised and non-randomised controlled trials investigating resistance exercise as the dominant treatment class, reporting sufficient information regarding ≥2 components of exercise dose. RESULTS: A total of 110 studies were included in meta-analyses (148 treatment arms (TAs), 3953 participants), reporting on five tendinopathy locations (rotator cuff: 48 TAs; Achilles: 43 TAs; lateral elbow: 29 TAs; patellar: 24 TAs; gluteal: 4 TAs). Meta-regressions provided consistent evidence of greater pooled mean effect sizes for higher intensity therapies comprising additional external resistance compared with body mass only (large effect size domains: ß BodyMass: External = 0.50 (95% credible interval (CrI): 0.15 to 0.84; p=0.998); small effect size domains (ß BodyMass: External = 0.04 (95% CrI: -0.21 to 0.31; p=0.619)) when combined across tendinopathy locations or analysed separately. Greater pooled mean effect sizes were also identified for the lowest frequency (less than daily) compared with mid (daily) and high frequencies (more than once per day) for both effect size domains when combined or analysed separately (p≥0.976). Evidence for associations between training volume and pooled mean effect sizes was minimal and inconsistent. SUMMARY/CONCLUSION: Resistance exercise dose is poorly reported within tendinopathy management literature. However, this large meta-analysis identified some consistent patterns indicating greater efficacy on average with therapies prescribing higher intensities (through inclusion of additional loads) and lower frequencies, potentially creating stronger stimuli and facilitating adequate recovery.
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Treinamento Resistido , Tendinopatia , Humanos , Manguito Rotador , Terapia por Exercício , Patela , Tendinopatia/terapiaRESUMO
ß-Alanine (BA) is one of the most widely used sport supplements, due to its capacity to improve high-intensity exercise performance by increasing muscle carnosine (MCarn) content, and consequently, the buffering capacity of the muscle. BA is also available in a variety of animal foods, but little is currently known about the influence of dietary BA intake on MCarn. The aim of the current study was to compile a detailed summary of available data on the BA content of commonly consumed foods, and to explore whether associations could be detected between self-reported dietary BA intake and skeletal MCarn in a group of 60 healthy, active, omnivorous men and women. Dietary BA intake was assessed via 3-day food records, and MCarn content assessed by high-performance liquid chromatography. A series of univariate and multivariate linear regression models were used to explore associations between estimated dietary BA and MCarn. No evidence of associations between dietary BA intake and MCarn were identified, with effect sizes close to zero calculated from models accounting for key demographic variables (f2 ≤ 0.02 for all analyses). These findings suggest that capacity to increase MCarn via dietary strategies may be limited, and that supplementation may be required to induce increases of the magnitude required to improve performance.
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Carnosina , Animais , Feminino , Dieta , Suplementos Nutricionais , Músculo Esquelético , beta-AlaninaRESUMO
ABSTRACT: Hall, AJ, Aspe, RR, Craig, TP, Kavaliauskas, M, Babraj, J, and Swinton, PA. The effects of sprint interval training on physical performance: a systematic review and meta-analysis. J Strength Cond Res 37(2): 457-481, 2023-The present study aimed to synthesize findings from published research and through meta-analysis quantify the effect of sprint interval training (SIT) and potential moderators on physical performance outcomes (categorized as aerobic, anaerobic, mixed aerobic-anaerobic, or muscular force) with healthy adults, in addition to assessing the methodological quality of included studies and the existence of small study effects. Fifty-five studies were included (50% moderate methodological quality, 42% low methodological quality), with 58% comprising an intervention duration of ≤4 weeks and an array of different training protocols. Bayesian's meta-analysis of standardized mean differences (SMD) identified a medium effect of improved physical performance with SIT (ES 0.5 = 0.52; 95% credible intervals [CrI]: 0.42-0.62). Moderator analyses identified overlap between outcome types with the largest effects estimated for anaerobic outcomes (ES 0.5 = 0.61; 95% CrI: 0.48-0.75). Moderator effects were identified for intervention duration, sprint length, and number of sprints performed per session, with larger effects obtained for greater values of each moderator. A substantive number of very large effect sizes (41 SMDs > 2) were identified with additional evidence of extensive small study effects. This meta-analysis demonstrates that short-term SIT interventions are effective for developing moderate improvements in physical performance outcomes. However, extensive small study effects, likely influenced by researchers analyzing many outcomes, suggest potential overestimation of reported effects. Future research should analyze fewer a priori selected outcomes and investigate models to progress SIT interventions for longer-term performance improvements.
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Treinamento Intervalado de Alta Intensidade , Adulto , Humanos , Treinamento Intervalado de Alta Intensidade/métodos , Teorema de Bayes , Força Muscular , Desempenho Físico FuncionalRESUMO
Studies have suggested a potential role of endothelial dysfunction and atherosclerosis in the pathophysiology of COVID-19. Herein, we tested whether brachial flow-mediated dilation (FMD) and carotid intima-media thickness (cIMT) measured upon hospital admission are associated with acute in-hospital outcomes in patients hospitalized with COVID-19. A total of 211 patients hospitalized with COVID-19 were submitted to assessments of FMD and mean and maximum cIMT (cIMTmean and cIMTmax) within the first 72 h of hospital admission. Study primary outcome was a composite of intensive care unit admission, mechanical ventilation, or death during the hospitalization. These outcomes were also considered independently. Thrombotic events were included as a secondary outcome. Odds ratios (ORs) and confidence intervals (CIs) were calculated using unadjusted and adjusted multivariable logistic regression models. Eighty-eight (42%) participants demonstrated at least one of the composite outcomes. cIMTmean and cIMTmax were predictors of mortality and thrombotic events in the univariate analysis (cIMTmean and mortality: unadjusted OR 12.71 [95% CI 1.71-94.48]; P = 0.014; cIMTmean and thrombotic events: unadjusted OR 11.94 [95% CI 1.64-86.79]; P = 0.015; cIMTmax and mortality: unadjusted OR 8.47 [95% CI 1.41-51.05]; P = 0.021; cIMTmax and thrombotic events: unadjusted OR 12.19 [95% CI 2.03-73.09]; P = 0.007). However, these associations were no longer present after adjustment for potential confounders (P > 0.05). In addition, FMD% was not associated with any outcome. In conclusion, cIMT and FMD are not independent predictors of clinical outcomes in patients hospitalized with COVID-19. These results suggest that subclinical atherosclerosis and endothelial dysfunction may not be the main drivers of COVID-19 complications in patients hospitalized with COVID-19.NEW & NOTEWORTHY Studies have suggested a role of endothelial dysfunction and atherosclerosis in COVID-19 pathophysiology. In this prospective cohort study, we assessed the prognostic value of carotid intima-media thickness (IMT) and flow-mediated dilation (FMD) in patients with COVID-19. Carotid IMT and FMD were not independent predictors of major outcomes. These results suggest that other risk factors may be the main drivers of clinical outcomes in patients with COVID-19.
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Aterosclerose , COVID-19 , Artéria Braquial , Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Dilatação , Endotélio Vascular , Hospitalização , Hospitais , Humanos , Estudos Prospectivos , Fatores de Risco , Ultrassonografia , Vasodilatação/fisiologiaRESUMO
OBJECTIVES: To investigate whether physical activity is associated with enhanced immunogenicity of a SARS-CoV-2 inactivated vaccine (Coronavac) in patients with autoimmune rheumatic diseases (ARD) (n = 898) and in non-ARD (n = 197) individuals without pre-existing immunogenicity to SARS-CoV-2. METHODS: This was a prospective cohort study within an open-label, single-arm, phase 4 vaccination trial. Immunogenicity was assessed after vaccination by measuring seroconversion rates of total anti-SARS-CoV-2 S1/S2 IgG (SC), geometric mean titers of anti-S1/S2 IgG (GMT), factor-increase in GMT (FI-GMT), frequency of neutralizing antibody (NAb), and median neutralizing activity. Physical activity (active being defined as ≥ 150 min/week) and sedentary behavior (>8h/day) were assessed by questionnaire. RESULTS: Physically active ARD patients (n = 494) were younger and less frequently used prednisone/biologics than inactive patients (n = 404). After controlling for covariates, active patients exhibited greater SC (OR: 1.4 [95%CI: 1.1-2.0]), GMT (32% [95%CI: 8.8-60) and FI-GMT (33% [95%CI: 9.6-63%]) vs. inactive. Cluster analysis (physical activity/sedentary status) revealed greater GMT (43.0% [95% CI: 11.0-84.0%) and FI-GMT (48.0% [95%CI: 14.0-92.0%]) in active/non-sedentary vs. inactive/sedentary ARD patients. A dose-response was observed, with greater benefits for the group of patients performing ≥ 350 min/week of physical activity (OR: 1.6 [95%CI: 1.1-2.4]; 41% [95%CI: 10-80%]; 35% [95%CI: 4.3-74], for SC, GMT, and FI-GMT, respectively) vs. the least active group (≤30 min/week). Greater SC (OR: 9.9 [95%CI: 1.1-89.0]) and GMT (26% [95%CI: 2.2-56.0%]) were observed in active vs. inactive non-ARD. CONCLUSIONS: A physically active lifestyle may enhance SARS-CoV-2 vaccine immunogenicity, a finding of particular clinical relevance for immunocompromised patients. TRIAL REGISTRATION: Clinicaltrials.gov #NCT04754698.
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COVID-19 , Doenças Reumáticas , Vacinas contra COVID-19 , Exercício Físico , Humanos , Estudos Prospectivos , SARS-CoV-2 , Vacinas de Produtos InativadosRESUMO
This prospective cohort study within an open-label, single-arm, phase 4 vaccination trial (clinicaltrials.gov #NCT04754698) aimed to investigate the association between physical activity and persistent anti-SARS-CoV-2 antibodies 6 months after two-dose schedule of CoronaVac in autoimmune rheumatic diseases (ARD) patients (n = 748). Persistent immunogenicity 6 months after the full-course vaccination was assessed using seroconversion rates of total anti-SARS-CoV-2 S1/S2 IgG, geometric mean titers of anti-S1/S2 IgG (GMT), and frequency of positive neutralizing antibodies (NAb). Physical activity was assessed trough questionnaire. Adjusted point estimates from logistic regression models indicated that physically active patients had greater odds of seroconversion rates (OR: 1.5 [95%CI: 1.1 to 2.1]) and NAb positivity (OR: 1.5 [95%CI: 1.0 to 2.1]), and approximately 43% greater GMT (42.8% [95%CI: 11.9 to 82.2]) than inactive ones. In conclusion, among immunocompromised patients, being physically active was associated with an increment in antibody persistence through 6 months after a full-course of an inactivated SARS-CoV-2 vaccine.
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Vacinas contra COVID-19 , COVID-19 , Anticorpos Antivirais , Exercício Físico , Humanos , Hospedeiro Imunocomprometido , Imunoglobulina G , Estudos Prospectivos , SARS-CoV-2RESUMO
Genome-wide association studies found that increased risk for atrial fibrillation (AF), the most common human heart arrhythmia, is associated with noncoding sequence variants located in proximity to PITX2 Cardiomyocyte-specific epigenomic and comparative genomics uncovered 2 AF-associated enhancers neighboring PITX2 with varying conservation in mice. Chromosome conformation capture experiments in mice revealed that the Pitx2c promoter directly contacted the AF-associated enhancer regions. CRISPR/Cas9-mediated deletion of a 20-kb topologically engaged enhancer led to reduced Pitx2c transcription and AF predisposition. Allele-specific chromatin immunoprecipitation sequencing on hybrid heterozygous enhancer knockout mice revealed that long-range interaction of an AF-associated region with the Pitx2c promoter was required for maintenance of the Pitx2c promoter chromatin state. Long-range looping was mediated by CCCTC-binding factor (CTCF), since genetic disruption of the intronic CTCF-binding site caused reduced Pitx2c expression, AF predisposition, and diminished active chromatin marks on Pitx2 AF risk variants located at 4q25 reside in genomic regions possessing long-range transcriptional regulatory functions directed at PITX2.
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Fibrilação Atrial/genética , Elementos Facilitadores Genéticos , Predisposição Genética para Doença , Proteínas de Homeodomínio/genética , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Animais , Sistemas CRISPR-Cas , Mapeamento Cromossômico , Epigênese Genética , Estudo de Associação Genômica Ampla , Camundongos , Camundongos Knockout , Proteína Homeobox PITX2RESUMO
The purpose of this research was to assess relationships between subjective and external measures of training load in professional youth footballers, whilst accounting for the effect of the stage of the season. Data for ratings of perceived exertion (RPE) and seven global positioning systems (GPS) derived measures were collected from 20 players (age = 17.4 ± 1.3 yrs, height = 178.0 ± 8.1 cm, mass = 71.8 ± 7.2 kg) across a 47-week season. The season was categorised by a pre-season phase, and two competitive phases (Comp1, Comp2). The structure of the data were investigated using principal component analysis. An extraction criterion of component with eigenvalues ≥1.0 was used. Two components were retained for the pre-season period explaining a cumulative variance of 77.1%. Single components were retained for both Comp1 and Comp2 explaining 73.3% and 74.3% of variance, respectively. Identification of single components may suggest that measures are related and can be used interchangeably, however these interpretations should be considered with caution. The identification of multiple components in the pre-season phase suggests that univariate measures may not be sufficient when considering load experienced. These results suggest that factoring load based on measures of volume and intensity should be considered.
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Condicionamento Físico Humano , Futebol , Adolescente , Sistemas de Informação Geográfica , Humanos , Esforço Físico , Análise de Componente Principal , Estações do AnoRESUMO
The magnitude of change following strength and conditioning (S&C) training can be evaluated comparing effect sizes to thresholds. This study conducted a series of meta-analyses and compiled results to identify thresholds specific to S&C, and create prior distributions for Bayesian updating. Pre- and post-training data from S&C interventions were translated into standardised mean difference (SMDpre) and percentage improvement (%Improve) effect sizes. Bayesian hierarchical meta-analysis models were conducted to compare effect sizes, develop prior distributions, and estimate 0.25-, 0.5-, and 0.75-quantiles to determine small, medium, and large thresholds, respectively. Data from 643 studies comprising 6574 effect sizes were included in the analyses. Large differences in distributions for both SMDpre and %Improve were identified across outcome domains (strength, power, jump and sprint performance), with analyses of the tails of the distributions indicating potential large overestimations of SMDpre values. Future evaluations of S&C training will be improved using Bayesian approaches featuring the information and priors developed in this study. To facilitate an uptake of Bayesian methods within S&C, an easily accessible tool employing intuitive Bayesian updating was created. It is recommended that the tool and specific thresholds be used instead of isolated effect size calculations and Cohen's generic values when evaluating S&C training.
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Treinamento Resistido , Humanos , Teorema de BayesRESUMO
This study aims to investigate the relationship between subjective and external measures of load in professional youth football players whilst accounting for the effect of training theme or competition. Data from ratings of perceived exertion and global positioning system-derived measures of external training load were collected from 20 professional youth players (age=17.4±1.3 yrs) across a 46-week season. General characteristics of training sessions were categorised based on their proximity to match day. The underlying structure of the data was investigated with principal component analysis. An extraction criterion comprising eigenvalues >1 was used to identify which components to retain. Three components were retained for training performed three days prior to match day (80.2% of variance), with two components (72.9-89.7% of variance) retained for all other modes. Generally, the first component was represented by measures of volume (Total Distance, PlayerLoad and low intensity running) whilst the second and third components were characterised by measures of intensity. Identification of multiple components indicates that load monitoring should comprise multiple variables. Additionally, differences in the underlying structure across training days that reflected different goals suggest that effective monitoring should be specific to the demands of different session types.
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Esforço Físico/fisiologia , Corrida/fisiologia , Futebol/fisiologia , Adolescente , Sistemas de Informação Geográfica , Humanos , Masculino , Análise de Componente PrincipalRESUMO
This study determined the influence of a high- (HI) versus low-intensity (LI) cycling warm-up on blood acid-base responses and exercise capacity following ingestion of sodium bicarbonate (SB; 0.3 g/kg body mass) or a placebo (PLA; maltodextrin) 3 hr prior to warm-up. Twelve men (21 ± 2 years, 79.2 ± 3.6 kg body mass, and maximum power output [Wmax] 318 ± 36 W) completed a familiarization and four double-blind trials in a counterbalanced order: HI warm-up with SB, HI warm-up with PLA, LI warm-up with SB, and LI warm-up with PLA. LI warm-up was 15 min at 60% Wmax, while the HI warm-up (typical of elites) featured LI followed by 2 × 30 s (3-min break) at Wmax, finishing 30 min prior to a cycling capacity test at 110% Wmax. Blood bicarbonate and lactate were measured throughout. SB supplementation increased blood bicarbonate (+6.4 mmol/L; 95% confidence interval, CI [5.7, 7.1]) prior to greater reductions with HI warm-up (-3.8 mmol/L; 95% CI [-5.8, -1.8]). However, during the 30-min recovery, blood bicarbonate rebounded and increased in all conditions, with concentrations â¼5.3 mmol/L greater with SB supplementation (p < .001). Blood bicarbonate significantly declined during the cycling capacity test at 110%Wmax with greater reductions following SB supplementation (-2.4 mmol/L; 95% CI [-3.8, -0.90]). Aligned with these results, SB supplementation increased total work done during the cycling capacity test at 110% Wmax (+8.5 kJ; 95% CI [3.6, 13.4], â¼19% increase) with no significant main effect of warm-up intensity (+0.0 kJ; 95% CI [-5.0, 5.0]). Collectively, the results demonstrate that SB supplementation can improve HI cycling capacity irrespective of prior warm-up intensity, likely due to blood alkalosis.
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Alcalose , Substâncias para Melhoria do Desempenho , Adulto , Ciclismo , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino , Bicarbonato de Sódio/farmacologiaRESUMO
Currently, little is known about the extent of interindividual variability in response to beta-alanine (BA) supplementation, nor what proportion of said variability can be attributed to external factors or to the intervention itself (intervention response). To investigate this, individual participant data on the effect of BA supplementation on a high-intensity cycling capacity test (CCT110%) were meta-analyzed. Changes in time to exhaustion (TTE) and muscle carnosine were the primary and secondary outcomes. Multilevel distributional Bayesian models were used to estimate the mean and SD of BA and placebo group change scores. The relative sizes of group SDs were used to infer whether observed variation in change scores were due to intervention or non-intervention-related effects. Six eligible studies were identified, and individual data were obtained from four of these. Analyses showed a group effect of BA supplementation on TTE (7.7, 95% credible interval [CrI] [1.3, 14.3] s) and muscle carnosine (18.1, 95% CrI [14.5, 21.9] mmol/kg DM). A large intervention response variation was identified for muscle carnosine (σIR = 5.8, 95% CrI [4.2, 7.4] mmol/kg DM) while equivalent change score SDs were shown for TTE in both the placebo (16.1, 95% CrI [13.0, 21.3] s) and BA (15.9, 95% CrI [13.0, 20.0] s) conditions, with the probability that SD was greater in placebo being 0.64. In conclusion, the similarity in observed change score SDs between groups for TTE indicates the source of variation is common to both groups, and therefore unrelated to the supplement itself, likely originating instead from external factors such as nutritional intake, sleep patterns, or training status.
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Ciclismo/fisiologia , Carnosina/metabolismo , Suplementos Nutricionais , Tolerância ao Exercício/fisiologia , Músculo Esquelético/metabolismo , beta-Alanina/administração & dosagem , Teorema de Bayes , Viés , Método Duplo-Cego , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fenômenos Fisiológicos da Nutrição Esportiva , Fatores de TempoRESUMO
In this article, the authors assessed the cost-effectiveness of center-based exercise training for older Australians. The participants were recipients of in-home care services, and they completed 24 weeks of progressive resistance plus balance training. Transport was offered to all participants. A stepped-wedge randomized control trial produced pre-, post-, and follow-up outcomes and cost data, which were used to calculate incremental cost-effectiveness ratios per quality-adjusted life year gained. Analyses were conducted from a health provider perspective and from a government perspective. From a health-service provider perspective, the direct cost of program provision was $303 per person, with transport adding an additional $1,920 per person. The incremental cost-utility ratio of the program relative to usual care was $70,540 per quality-adjusted life year over 6 months, decreasing to $37,816 per quality-adjusted life year over 12 months. The findings suggest that Muscling Up Against Disability offers good value for the money within commonly accepted threshold values.
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OBJECTIVE: To investigate the associations of balance confidence with physical and cognitive markers of well-being in older adults receiving government-funded aged care services and whether progressive resistance plus balance training could positively influence change. DESIGN: Intervention study. SETTING: Community-based older adult-specific exercise clinic. PARTICIPANTS: Older adults (N=245) with complex care needs who were receiving government-funded aged care support. INTERVENTIONS: Twenty-four weeks of twice weekly progressive resistance plus balance training carried out under the supervision of accredited exercise physiologists. MAIN OUTCOME MEASURES: The primary measure was the Activity-specific Balance Confidence Scale. Secondary measures included the Short Physical Performance Battery; fall history gathered as part of the health history questionnaire; hierarchical timed balance tests; Geriatric Anxiety Index; Geriatric Depression Scale; Fatigue, Resistance, Ambulation, Illness, Loss of Weight scale; and EuroQoL-5 dimension 3 level. RESULTS: At baseline, better physical performance (r=.54; P<.01) and quality of life (r=.52; P<.01) predicted better balance confidence. In contrast, at baseline, higher levels of frailty predicted worse balance confidence (r=-.55; P<.01). Change in balance confidence after the exercise intervention was accompanied by improved physical performance (+12%) and reduced frailty (-11%). Baseline balance confidence was identified as the most consistent negative predictor of change scores across the intervention. CONCLUSIONS: This study shows that reduced physical performance and quality of life and increased frailty are predictive of worse balance confidence in older adults with aged care needs. However, when a targeted intervention of resistance and balance exercise is implemented that reduces frailty and improves physical performance, balance confidence will also improve. Given the influence of balance confidence on a raft of well-being determinants, including the capacity for positive physical and cognitive change, this study offers important insight to those looking to reduce falls in older adults.
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Pessoas com Deficiência/reabilitação , Serviços de Saúde para Idosos/organização & administração , Equilíbrio Postural/fisiologia , Treinamento Resistido , Idoso , Austrália , Avaliação da Deficiência , Feminino , Avaliação Geriátrica , Humanos , Masculino , Qualidade de Vida , Inquéritos e Questionários , Resultado do TratamentoRESUMO
This study investigated the association of sitting time with sarcopenia and physical performance in residential aged care residents at baseline and 18-month follow-up. Measures included the International Physical Activity Questionnaire (sitting time), European Working Group definition of sarcopenia, and the short physical performance battery (physical performance). Logistic regression and linear regression analyses were used to investigate associations. For each hour of sitting, the unadjusted odds ratio of sarcopenia was 1.16 (95% confidence interval [0.98, 1.37]). Linear regression showed that each hour of sitting was significantly associated with a 0.2-unit lower score for performance. Associations of baseline sitting with follow-up sarcopenia status and performance were nonsignificant. Cross-sectionally, increased sitting time in residential aged care may be detrimentally associated with sarcopenia and physical performance. Based on current reablement models of care, future studies should investigate if reducing sedentary time improves performance among adults in end of life care.
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Desempenho Físico Funcional , Sarcopenia/epidemiologia , Comportamento Sedentário , Postura Sentada , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Instituição de Longa Permanência para Idosos , Humanos , MasculinoRESUMO
PURPOSE: Evaluate the effectiveness of workplace interventions to improve sitting posture of workers that spend long periods of time seated at a visual display terminal. METHODS: A systematic review of randomised controlled trials, non-randomised controlled trials and single-group intervention trials featuring workplace interventions with pre- and follow-up measurements of sitting posture was conducted (registered in PROSPERO, CRD#42015027648). Nine databases were searched for studies available between January 2005 and February 2016. RESULTS: 2519 articles were screened with 12 studies meeting the inclusion criteria. The included studies featured various ergonomic workplace interventions and comprised 4 randomised controlled trial (n=457), 2 non-randomised controlled trials (n=416) and 6 single-group intervention trials (n=328). Due to clinical and methodological heterogeneity, pooling of data was not completed and a narrative summary of findings was developed using the Grading of Recommendations Assessment Development and Evaluation (GRADE) framework. The evidence for four review outcomes was assessed with medium to large positive improvements obtained for the majority of studies investigating changes to gross sitting posture, whereas mixed findings were obtained for more specific local segment assessments of sitting posture. The overall evidence quality for all review outcomes were identified as either 'low' or 'very low'. CONCLUSION: There is evidence which is limited in quality to indicate that ergonomic workplace interventions can improve gross sitting posture. More high quality research across a range of intervention types is required with longer follow-up durations and more advanced methods to assess sitting posture with greater frequency and less bias.
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Medicina Baseada em Evidências , Postura/fisiologia , Local de Trabalho/normas , Computadores/estatística & dados numéricos , Ergonomia/normas , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: To conduct a systematic review and meta-analysis of the evidence on the effects of ß-alanine supplementation on exercise capacity and performance. DESIGN: This study was designed in accordance with PRISMA guidelines. A 3-level mixed effects model was employed to model effect sizes and account for dependencies within data. DATA SOURCES: 3 databases (PubMed, Google Scholar, Web of Science) were searched using a number of terms ('ß-alanine' and 'Beta-alanine' combined with 'supplementation', 'exercise', 'training', 'athlete', 'performance' and 'carnosine'). ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Inclusion/exclusion criteria limited articles to double-blinded, placebo-controlled studies investigating the effects of ß-alanine supplementation on an exercise measure. All healthy participant populations were considered, while supplementation protocols were restricted to chronic ingestion. Cross-over designs were excluded due to the long washout period for skeletal muscle carnosine following supplementation. A single outcome measure was extracted for each exercise protocol and converted to effect sizes for meta-analyses. RESULTS: 40 individual studies employing 65 different exercise protocols and totalling 70 exercise measures in 1461 participants were included in the analyses. A significant overall effect size of 0.18 (95% CI 0.08 to 0.28) was shown. Meta-regression demonstrated that exercise duration significantly (p=0.004) moderated effect sizes. Subgroup analyses also identified the type of exercise as a significant (p=0.013) moderator of effect sizes within an exercise time frame of 0.5-10â min with greater effect sizes for exercise capacity (0.4998 (95% CI 0.246 to 0.753)) versus performance (0.1078 (95% CI -0.201 to 0.416)). There was no moderating effect of training status (p=0.559), intermittent or continuous exercise (p=0.436) or total amount of ß-alanine ingested (p=0.438). Co-supplementation with sodium bicarbonate resulted in the largest effect size when compared with placebo (0.43 (95% CI 0.22 to 0.64)). SUMMARY/CONCLUSIONS: ß-alanine had a significant overall effect while subgroup analyses revealed a number of modifying factors. These data allow individuals to make informed decisions as to the likelihood of an ergogenic effect with ß-alanine supplementation based on their chosen exercise modality.
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Desempenho Atlético/fisiologia , Suplementos Nutricionais , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , beta-Alanina/farmacologia , Carnosina/química , Humanos , Músculo Esquelético/química , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
This study aimed to assess the effect of extreme environmental exposure during an operational saturation dive on airway inflammation (exhaled nitric oxide (FeNo)), components of fitness (flexibility and aerobic capacity) and blood hematological variables. Six saturation divers, who undertook a 26±0.5 day operational saturation dive were recruited to take part in this study. Participants completed a field-based repeated measure test battery on three occasions (pre-dive, post-dive and 24 hours after saturation dive). Hemoglobin concentration was significantly (P⟨0.001) reduced from pre- (15.3±0.8 g/dL) to post-saturation (14.25±1.2 g/dL) dive but recovered toward baseline values within 24 hours (15.13±1.03 g/dL; P=0.04). Similarly, a reduction in plasma volume was observed in all participants from pre- to post-saturation dive trials. Airway inflammation response was non-significant, although a large inter-individual response was evident. Hip flexion, assessed by the sit and reach test did not change following the saturation dive. Data on aerobic capacity was collected in one participant only, due to practical difficulties in participant access. In summary, this is the first investigation to conduct a multiple-component field-based study on operational saturation divers. The findings for this exploratory study present interesting groundings for further investigation.
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Mergulho/fisiologia , Adulto , Mergulho/efeitos adversos , Expiração/fisiologia , Hematócrito , Hemoglobinas/metabolismo , Humanos , Inflamação/etiologia , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/fisiologia , Consumo de Oxigênio/fisiologia , Aptidão Física/fisiologia , Projetos Piloto , Fenômenos Fisiológicos RespiratóriosRESUMO
The consequences of and transition into sarcopenia with long-term survival was investigated in the nursing home setting. Eligible residents from 11 nursing homes were followed-up 18-months after their assessment for sarcopenia using the European Working Group on Sarcopenia in Older People criteria, with other demographic, physical and cognitive health measures collected. Of the 102 older adults who consented at baseline, 22 had died and 58 agreed to participate at follow-up, 51.7% of whom had sarcopenic. Sarcopenia at baseline was associated with a depression (p < .001), but not mortality, hospitalization, falls or cognitive decline at follow-up. Age was the strongest predictor of mortality (p = .05) with the relative risk of death increasing 5.2% each year. The prevalence of sarcopenia is high and increases with long-term survival in end-of-life care. However, the risk of sarcopenia-related mortality is not as great as from increasing age alone.