Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Int J Biometeorol ; 68(7): 1235-1252, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38691211

RESUMO

There are concerns regarding high surface temperatures on synthetic grass sports surfaces influencing the surrounding thermal environment, potentially increasing heat stress and impacting athlete safety. As such, studies have investigated changes to the thermal environment surrounding synthetic grass surfaces in comparison to both natural grass, and synthetic surfaces with different features, but this body of research has not been systematically reviewed. Therefore, this systematic review aimed to (i) determine if there are differences in the thermal environment surrounding synthetic grass surfaces compared with natural grass surfaces, and (ii) determine if there are differences in the thermal environment between different types of synthetic grass surfaces. A systematic review adhering to the PRISMA guidelines was performed. The eligibility criteria required investigations to report at least one of the following environmental parameters on or directly above both a synthetic surface and a comparator group of either natural grass or an alternative synthetic grass surface used in sport: Air temperature, mean radiant temperature, humidity, wind velocity, unified heat stress indices (i.e. wet-bulb-globe temperature and heat index) and/or surface temperature. Twenty-three studies were identified. The only parameters that were consistently higher on synthetic grass compared to natural grass were the air temperature (range: 0.5-1.2 °C) and surface temperature (range: 9.4-33.7 °C), while the mean radiant temperature, humidity, wind velocity and wet-bulb-globe temperature remained similar or required more data to determine if any differences exist. Synthetic grass surfaces consisting of styrene butadiene rubber infill or a shock pad had increased surface temperatures, whereas surfaces with thermoplastic elastomer infill, Cool climate turf fibres or HydroChill had lower surface temperatures. This systematic review has demonstrated that air and surface temperatures can be increased on synthetic sports surfaces, compared to natural grass surfaces. However, it is uncertain whether the differences are enough to increase an individual's heat stress risk and cause concern for athlete safety. While modifications to the turf infill or fibres can reduce synthetic surface temperatures, the effect of these features on the thermal environment as a whole is unclear. This review was prospectively registered with the Open Science Framework (Open Science Framework registration   https://doi.org/10.17605/OSF.IO/BTKGE ).


Assuntos
Poaceae , Esportes , Humanos , Temperatura , Propriedades de Superfície
2.
Aust J Rural Health ; 32(2): 286-298, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38337146

RESUMO

OBJECTIVE: Most podiatry-led high-risk foot services (HRFS) in Australia are located in metropolitan areas or large regional centres. In rural areas, where there are limited specialist services, individuals with diabetes-related foot ulceration are more likely to undergo amputation. This study aimed to explore clinicians' perceptions of a recently implemented HRFS in rural New South Wales, Australia, and compare trends of amputation and hospitalisation prior to and post-implementation of the service. SETTING: Rural HRFS in Tamworth, New South Wales, Australia. PARTICIPANTS: Health professionals working within the HRFS were recruited to participate. DESIGN: This was a multiple-methods study. For the qualitative arm, semi-structured interviews were conducted, which were analysed using a reflexive thematic approach. The quantitative arm of the study utilised a retrospective analytic design which applied an interrupted time series to compare amputation and hospitalisation trends pre- and post-implementation of the HRFS utilising diagnostic and procedural ICD codes. RESULTS: The qualitative arm of the study derived three themes: (1) navigating the divide, (2) rural community and rural challenges and (3) professional identity. Results of the interrupted time series indicate that there was a downward trend in major amputations following implementation of the HRFS; however, this was not statistically significant. CONCLUSION: Clinicians were aware of the inequity in DFD outcomes between rural and metropolitan areas and were committed to improving outcomes, particularly with respect to First Nations peoples. Future research will explore service use and amputation rates in the longer term to further evaluate this specialised multidisciplinary care in a rural community.


Assuntos
Amputação Cirúrgica , Pé Diabético , Serviços de Saúde Rural , Humanos , Serviços de Saúde Rural/estatística & dados numéricos , New South Wales , Amputação Cirúrgica/estatística & dados numéricos , Feminino , Masculino , Pesquisa Qualitativa , Estudos Retrospectivos , Podiatria , Adulto , Pessoa de Meia-Idade , Hospitalização/estatística & dados numéricos , População Rural/estatística & dados numéricos
3.
Aust Occup Ther J ; 71(4): 612-626, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38296464

RESUMO

INTRODUCTION: Pressure injuries are a preventable yet highly prevalent health concern. Wheelchair cushion prescription can have significant implications for wheelchair users' risk of pressure injury development, which can impact functional abilities and quality of life. The efficacy of a wheelchair cushion to redistribute pressure has been well-researched, but the efficacy to manage the microclimate is less clear, particularly in warm-hot environments. The aim of this study was to systematically review studies examining the effect of wheelchair cushions on temperature, moisture and thermal perception to determine which cushions are superior to improve these responses. METHOD: A systematic review with meta-analyses of randomised cross-over and randomised control trials of wheelchair cushion interventions on measures of temperature, moisture, and thermal perception was conducted. RESULTS: Eight studies were identified that met the eligibility criteria and six meta-analyses were conducted. Pooled analyses identified a significantly lower temperature on foam-gel cushions compared to air cushions (MD = 0.80, 95% CI: 0.31, 1.29; p = 0.002) and a significantly lower temperature on foam-gel cushions compared to foam cushions (SMD = 0.76, 95%CI; 0.45, 1.06; p < 0.00001). Pooled analyses also demonstrated significantly lower relative humidity (i.e., moisture) on foam cushions compared to foam-gel cushions (p = 0.02). Differences in thermal perception were inconclusive due to limited data found. CONCLUSION: It is clear that not one cushion is ideal in managing all aspects of microclimate, as foam-gel cushions were the superior cushion to manage temperature and foam cushions were the superior cushion to manage moisture. This article provides occupational therapists and other health professionals with evidence-based information to assist with wheelchair cushion prescription that minimises the temperature and moisture accumulation, and associated risk of pressure injury for wheelchair users.


Assuntos
Desenho de Equipamento , Microclima , Úlcera por Pressão , Cadeiras de Rodas , Humanos , Úlcera por Pressão/prevenção & controle , Temperatura , Terapia Ocupacional/métodos
4.
Environ Microbiol ; 25(8): 1409-1423, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36871189

RESUMO

Methylmercury (MeHg) production is controlled by the bioavailability of inorganic divalent mercury (Hg(II)i ) and Hg-methylation capacity of the microbial community (conferred by the hgcAB gene cluster). However, the relative importance of these factors and their interaction in the environment remain poorly understood. Here, metagenomic sequencing and a full-factorial MeHg formation experiment were conducted across a wetland sulfate gradient with different microbial communities and pore water chemistries. From this experiment, the relative importance of each factor on MeHg formation was isolated. Hg(II)i bioavailability correlated with the dissolved organic matter composition, while the microbial Hg-methylation capacity correlated with the abundance of hgcA genes. MeHg formation responded synergistically to both factors. Notably, hgcA sequences were from diverse taxonomic groups, none of which contained genes for dissimilatory sulfate reduction. This work expands our understanding of the geochemical and microbial constraints on MeHg formation in situ and provides an experimental framework for further mechanistic studies.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Microbiota , Poluentes Químicos da Água , Metilação , Disponibilidade Biológica , Poluentes Químicos da Água/análise
5.
Diabet Med ; 40(1): e14951, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36054775

RESUMO

OBJECTIVE: Diabetes-related foot ulceration (DFU) is a common limb-threatening condition, which is complex and subsequently challenging to manage. The aim of this study was to determine the contribution of a range of clinical and social factors to the healing of diabetes-related foot ulceration in an Australian population. RESEARCH DESIGN AND METHODS: This was a prospective cohort study of individuals with diabetes-related foot ulceration (DFU). Age, sex, medical history, medications, dietary supplementation (e.g. vitamin C intake) and smoking history were elicited at baseline. The index of relative socio-economic disadvantage (IRSD) was calculated. The Australian Eating Survey and International Physical Activity Questionnaire-short were administered. Wound history, size, grade, time to healing and infection were captured and monitored over 6 months. Logistic regression was performed to determine the relationship between healing and diet quality, toe systolic pressure, wound size at, IRSD, infection and previous amputation. RESULTS: A total of 117 participants were included. The majority were male n = 96 (82%), socio-economically disadvantaged (mean IRSD 965, SD 60), and obese (BMI 36 kg/m2 , SD 11) with a long history of diabetes (20 years, SD 11). Wounds were predominantly neuropathic (n = 85, 73%) and classified 1A (n = 63, 54%) on the University of Texas wound classification system with few infections (n = 23, 16%). Dietary supplementation was associated with 4.36 increased odds of healing (95% 1.28-14.84, p = 0.02), and greater levels of socio-economic advantage were also associated with increased odds of healing (OR 1.01, 95% CI 1.01-1.02, p = 0.03). CONCLUSIONS: In this cohort study of predominantly neuropathic, non-infected DFU, individuals who had greater levels of socio-economic advantage had significantly greater odds of DFU healing. Diet quality was poor in most participants, with individuals taking supplementation significantly more likely to heal.


Assuntos
Diabetes Mellitus , Pé Diabético , Úlcera do Pé , Adulto , Masculino , Humanos , Feminino , Pé Diabético/epidemiologia , Pé Diabético/terapia , Estudos de Coortes , Estudos Prospectivos , Austrália/epidemiologia , Cicatrização
6.
Angew Chem Int Ed Engl ; 62(31): e202306583, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37277318

RESUMO

Cell encapsulation has been studied for various applications ranging from cell transplantation to biological production. However, current encapsulation technologies focus on cell protection rather than cell regulation that is essential to most if not all cell-based applications. Here we report a method for cell nanoencapsulation and regulation using an ultrathin biomimetic extracellular matrix as a cell nanocapsule to carry nanoparticles (CN2 ). This method allows high-capacity nanoparticle retention at the vicinity of cell surfaces. The encapsulated cells maintain high viability and normal metabolism. When gold nanoparticles (AuNPs) are used as a model to decorate the nanocapsule, light irradiation transiently increases the temperature, leading to the activation of the heat shock protein 70 (HSP70) promoter and the regulation of reporter gene expression. As the biomimetic nanocapsule can be decorated with any or multiple NPs, CN2 is a promising platform for advancing cell-based applications.


Assuntos
Nanopartículas Metálicas , Nanocápsulas , Nanopartículas , Ouro , Biomimética/métodos , Matriz Extracelular
7.
Circulation ; 143(1): 33-44, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33148016

RESUMO

BACKGROUND: Patients with elevated triglycerides despite statin therapy have increased risk for ischemic events, including coronary revascularizations. METHODS: REDUCE-IT (The Reduction of Cardiovascular Events with Icosapent Ethyl-Intervention Trial), a multicenter, double-blind, placebo-controlled trial, randomly assigned statin-treated patients with elevated triglycerides (135-499 mg/dL), controlled low-density lipoprotein (41-100 mg/dL), and either established cardiovascular disease or diabetes plus other risk factors to receive icosapent ethyl 4 g/d or placebo. The primary and key secondary composite end points were significantly reduced. Prespecified analyses examined all coronary revascularizations, recurrent revascularizations, and revascularization subtypes. RESULTS: A total of 8179 randomly assigned patients were followed for 4.9 years (median). First revascularizations were reduced to 9.2% (22.5/1000 patient-years) with icosapent ethyl versus 13.3% (33.7/1000 patient-years) with placebo (hazard ratio, 0.66 [95% CI, 0.58-0.76]; P<0.0001; number needed to treat for 4.9 years=24); similar reductions were observed in total (first and subsequent) revascularizations (negative binomial rate ratio, 0.64 [95% CI, 0.56-0.74]; P<0.0001), and across elective, urgent, and emergent revascularizations. Icosapent ethyl significantly reduced percutaneous coronary intervention (hazard ratio, 0.68 [95% CI, 0.59-0.79]; P<0.0001) and coronary artery bypass grafting (hazard ratio, 0.61 [95% CI, 0.45-0.81]; P=0.0005). CONCLUSIONS: Icosapent ethyl reduced the need for first and subsequent coronary revascularizations in statin-treated patients with elevated triglycerides and increased cardiovascular risk. To our knowledge, icosapent ethyl is the first non-low-density lipoprotein-lowering treatment that has been shown to reduce coronary artery bypass grafting in a blinded, randomized trial. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01492361.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Ácido Eicosapentaenoico/análogos & derivados , Revascularização Miocárdica/métodos , Inibidores da Agregação Plaquetária/uso terapêutico , Idoso , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus/fisiopatologia , Método Duplo-Cego , Ácido Eicosapentaenoico/uso terapêutico , Feminino , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Pessoa de Meia-Idade
8.
Wound Repair Regen ; 30(1): 24-33, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34698428

RESUMO

Australia has the second highest rate of non-traumatic lower extremity amputation (LEA) globally. Australia's large geographical size is one of the biggest challenges facing limb preservation services and may be contributing to LEA. The aim of this study was to determine what factors contribute to the likelihood of LEA in people with active foot ulceration in regional Australia. This retrospective cohort study audited patients with active foot ulceration in a multidisciplinary high risk foot service (HRFS) in regional Australia. Neurological, vascular and wound characteristics were systematically extracted, along with demographic information. Participants were followed for at least 12 months until healing or LEA occurred. Correlations between LEA and clinical and demographic characteristics were assessed using the Pearson's product moment correlation coefficient and chi squared test for independence. Significant variables (p < 0.05) were included in the model. Direct logistic regression assessed the independent contribution of significantly correlated variables on the likelihood of LEA. Of note, 1876 records were hand screened with 476 participants (25%) meeting the inclusion criteria. Geographical distance from the HRFS, toe systolic pressure (TSP), diabetes and infection were all significantly correlated with LEA and included in the logistic regression model. TSP decrease of 1 mmHg (OR 1.02, 95% CI 1.01-1.03), increased geographical distance (1 km) from HRFS (OR 1.006, 95% CI 1.001-1.01) infection (OR 2.08, 95% CI 1.06-4.07) and presence of diabetes (OR 3.77, 95% CI 1.12-12.65) were all significantly associated with increased likelihood of LEA. HRFS should account for the disparity in outcomes between patients living in close proximity to their service, compared to those in rural areas. Optimal management of diabetes, vascular perfusion and control of infection may also contribute to preventing LEA in people with active foot ulceration.


Assuntos
Pé Diabético , Amputação Cirúrgica , Pé Diabético/epidemiologia , Pé Diabético/cirurgia , Humanos , Extremidade Inferior/cirurgia , Estudos Retrospectivos , Fatores de Risco , Cicatrização
9.
J Sports Sci ; 40(13): 1486-1499, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35695484

RESUMO

The primary objective of this systematic review was to synthesise peer-reviewed quantitative research of outcomes associated with participation in parkrun. The secondary objective was to synthesise the quantitative research of factors influencing why, and how often, individuals participate in parkrun. Studies were identified via electronic search of Medline, AMED, CINAHL, Cochrane Library, Informit, PsychInfo, SportDiscus, and Web of Science, to 30 March 2021. Two reviewers independently assessed methodological quality. Eleven studies (18,203 participants) were included. Limited evidence from pre-post measure single-group prospective studies suggests parkrun participation promotes improvements in fitness, body mass index, physical activity levels, mood, and personal wellbeing. Individuals with non-running backgrounds generally had higher levels of participation. The main motivators to participate were to improve fitness and social interaction. Future attendance was most strongly correlated with historical attendance. There is a small evidence base for improvements in broad measures of physical and mental health from participation in parkrun. In addition, the study found improving physical fitness and social wellbeing were the main self-reported factors for participation in parkrun. Further research is needed to strengthen the knowledge base of the effects of parkrun to determine its efficacy as a health intervention strategy for physical and mental health.


Assuntos
Exercício Físico , Satisfação Pessoal , Humanos , Saúde Mental , Estudos Prospectivos , Autorrelato
10.
Environ Sci Technol ; 54(24): 15840-15851, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33228362

RESUMO

Mercury (Hg) methylation is a microbially mediated process that converts inorganic Hg into bioaccumulative, neurotoxic methylmercury (MeHg). The metabolic activity of methylating organisms is highly dependent on biogeochemical conditions, which subsequently influences MeHg production. However, our understanding of the ecophysiology of methylators in natural ecosystems is still limited. Here, we identified potential locations of MeHg production in the anoxic, sulfidic hypolimnion of a freshwater lake. At these sites, we used shotgun metagenomics to characterize microorganisms with the Hg-methylation gene hgcA. Putative methylators were dominated by hgcA sequences divergent from those in well-studied, confirmed methylators. Using genome-resolved metagenomics, we identified organisms with hgcA (hgcA+) within the Bacteroidetes and the recently described Kiritimatiellaeota phyla. We identified hgcA+ genomes derived from sulfate-reducing bacteria, but these accounted for only 22% of hgcA+ genome coverage. The most abundant hgcA+ genomes were from fermenters, accounting for over half of the hgcA gene coverage. Many of these organisms also mediate hydrolysis of polysaccharides, likely from cyanobacterial blooms. This work highlights the distribution of the Hg-methylation genes across microbial metabolic guilds and indicate that primary degradation of polysaccharides and fermentation may play an important but unrecognized role in MeHg production in the anoxic hypolimnion of freshwater lakes.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Anaerobiose , Ecossistema , Lagos , Mercúrio/análise , Metilação , Sulfatos
11.
J Thromb Thrombolysis ; 49(4): 522-526, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32166541

RESUMO

Patients with atrial fibrillation who undergo percutaneous coronary intervention are at increased risk for both coronary and cerebral thrombotic events. As a result, antithrombotic therapy for this patient population continues to pose a significant challenge. In this review, we discuss the development of warfarin triple therapy as the standard of care in the last century, the transition to dual therapy with warfarin and a P2Y12 inhibitor, the advent of NOACs, recent clinical trials, and new regimens with a NOAC and a P2Y12 inhibitor. We also discuss our current clinical practice, based on the available data.


Assuntos
Anticoagulantes/administração & dosagem , Fibrilação Atrial/complicações , Trombose Coronária/prevenção & controle , Trombose Intracraniana/prevenção & controle , Anticoagulantes/efeitos adversos , Aspirina/administração & dosagem , Cardiologia/tendências , Trombose Coronária/etiologia , Quimioterapia Combinada/efeitos adversos , Humanos , Trombose Intracraniana/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Varfarina/administração & dosagem
12.
BMC Musculoskelet Disord ; 20(1): 463, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31638962

RESUMO

INTRODUCTION: Globally, low back pain (LBP) is one of the greatest causes of disability. In people with LBP, dysfunction of muscles such as the gluteus medius have been demonstrated to increase spinal loading and reduce spinal stability. Differences in gluteus medius function have been reported in those with LBP compared to those without, although this has only been reported in individual studies. The aim of this systematic review was to determine if adults with a history, or current LBP, demonstrate differences in measures of gluteus medius function when compared to adults without LBP. METHODS: MEDLINE, EMBASE, AMED, PsycINFO, PubMED, Pro Quest Database, CINAHL and SPORTDiscus were searched from inception until December 2018 for published journal articles and conference abstracts. No language restrictions were applied. Only case-control studies with participants 18 years and over were included. Participants could have had any type and duration of LBP. Studies could have assessed gluteus medius function with any quantifiable clinical assessment or measurement tool, with the participant non-weight bearing or weight bearing, and during static or dynamic activity. Quality appraisal and data extraction were independently performed by two authors. RESULTS: The 24 included articles involved 1088 participants with LBP and 998 without LBP. The gluteus medius muscle in participants with LBP tended to demonstrate reduced strength and more trigger points compared to the gluteus medius muscle of those without LBP. The level of activity, fatigability, time to activate, time to peak activation, cross sectional area, and muscle thickness showed unclear results. Meta-analysis was not performed due to the heterogeneity of included studies. CONCLUSION: Clinically, the findings from this systematic review should be considered when assessing and managing patients with LBP. Future studies that clearly define the type and duration of LBP, and prospectively assess gluteus medius muscle function in those with and without LBP are needed. TRIAL REGISTRATION: PROSPERO ( CRD42017076773 ).


Assuntos
Dor Lombar/fisiopatologia , Músculo Esquelético/fisiopatologia , Nádegas , Humanos , Força Muscular
13.
Curr Cardiol Rep ; 20(11): 110, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30259187

RESUMO

PURPOSE OF REVIEW: This review aims to discuss the use of antithrombotic therapy in patients with atrial fibrillation who undergo coronary stenting with emphasis on the use of double vs triple therapy. RECENT FINDINGS: When combined with systemic anticoagulation, dual antiplatelet therapy results in an unacceptable increase in bleeding without any improvement in prevention of thrombotic events. Direct oral anticoagulants combined with single antiplatelet therapy have reduced bleeding compared with warfarin plus dual antiplatelet therapy. Triple anticoagulation therapy with warfarin or direct oral anticoagulants leads to an excess of bleeding and is not superior in preventing thrombotic events. Recent randomized, controlled trials have shown a significant reduction in major bleeding events in patients treated with dual antithrombotic therapy compared with triple therapy without any difference in efficacy. These findings call into question whether triple therapy should remain a part of standard practice.


Assuntos
Anticoagulantes/uso terapêutico , Antitrombinas/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Doença da Artéria Coronariana/terapia , Intervenção Coronária Percutânea/efeitos adversos , Stents , Anticoagulantes/efeitos adversos , Antitrombinas/efeitos adversos , Doença da Artéria Coronariana/complicações , Trombose Coronária/etiologia , Trombose Coronária/prevenção & controle , Quimioterapia Combinada , Hemorragia/induzido quimicamente , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Varfarina/efeitos adversos , Varfarina/uso terapêutico
14.
J Strength Cond Res ; 32(4): 1109-1113, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29324580

RESUMO

Lamoureux, NR, Tomkinson, GR, Peterson, BJ, and Fitzgerald, JS. Relationship between skating economy and performance during a repeated-shift test in elite and subelite ice hockey players. J Strength Cond Res 32(4): 1109-1113, 2018-The purpose of this study was to determine the importance of skating economy to fatigue during repeated high-intensity efforts of a simulated ice hockey shift. Forty-five collegiate and Junior A male ice hockey players (aged 18-24 years) performed a continuous graded exercise test using a skate treadmill. Breath-by-breath data for oxygen consumption (V[Combining Dot Above]O2) and respiratory exchange ratio were collected and used to derive energy expenditure (EE) averaged over the final 10 seconds of each stage. Economy was determined as the slope of the regression line relating V[Combining Dot Above]O2 and EE against skating speed separately. Participants also completed 8 bouts of maximal ice skating through a course designed to simulate typical shift, with timing gates determining first half, second half, and total fatigue decrement, calculated by a percent decrement score. Partial correlation was used to determine the association between economy measures and decrement during the repeated-shift test. Twenty-six participants met inclusion criteria and were included in data analysis. Skating economy measures (both relative V[Combining Dot Above]O2 and EE) were very likely moderate positive correlates of total fatigue decrement (r [95% confidence interval]: V[Combining Dot Above]O2, 0.46 [0.09, 0.72] and EE, 0.44, [0.06, 0.71]) but not with first or second gate decrement. Our results indicate that skating economy plays an important role in fatigue resistance over repeated on-ice sprints designed to simulate a typical shift. This supports the use of technical skating coaching and training techniques to enhance skating economy as a means of improving ice hockey performance.


Assuntos
Desempenho Atlético/fisiologia , Hóquei/fisiologia , Fadiga Muscular/fisiologia , Treinamento por Simulação/métodos , Patinação/fisiologia , Adolescente , Adulto , Atletas , Metabolismo Energético/fisiologia , Teste de Esforço/métodos , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Adulto Jovem
15.
J Exerc Sci Fit ; 16(1): 32-36, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30662490

RESUMO

BACKGROUND/OBJECTIVE: The relationship between ventilatory threshold (VT1, VT2) and repeated-sprint ability (RSA) in competitive male ice hockey players was investigated. METHODS: Forty-three male ice hockey players aged 18-23 years competing in NCAA Division I, NCAA Division III, and Junior A level participated. Participants performed an incremental graded exercise test on a skate treadmill to determine V ˙ O2peak, VT1, and VT2 using MedGraphics Breezesuit™ software (v-slope). Participants performed an on-ice repeated shift (RSA) test consisting of 8-maximal skating bouts, lasting approximately 25 s and interspersed with 90 s of passive recovery, to determine first gate, second gate, and total sprint decrement (%dec). Pearson product-moment correlations and multiple regressions were used to assess relationships between ventilatory threshold variables (VT1, VT2, Stage at VT1, and Stage at VT2) and RSA (first gate, second gate, and total course decrement). RESULTS: Stage at VT2 was the only variable substantially correlated with first gate (r = -0.35; P < 0.05), second gate (r = -0.58; P < 0.001) and total course decrement (r = -0.42; P < 0.05). CONCLUSION: The results of this study demonstrated that VT is substantially associated with RSA, and VT2 is more strongly correlated with RSA than V ˙ O2peak. This study suggests that longer duration high-intensity interval training at intensities that increase workrate at VT2 may lead to possible improvements in RSA.

16.
Neuroimage ; 131: 29-41, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26589333

RESUMO

Exercise improves cognition in humans and animals. Running increases neurogenesis in the dentate gyrus of the hippocampus, a brain area important for learning and memory. It is unclear how running modifies the circuitry of new dentate gyrus neurons to support their role in memory function. Here we combine retroviral labeling with rabies virus mediated trans-synaptic retrograde tracing to define and quantify new neuron afferent inputs in young adult male C57Bl/6 mice, housed with or without a running wheel for one month. Exercise resulted in a shift in new neuron networks that may promote sparse encoding and pattern separation. Neurogenesis increased in the dorsal, but not the ventral, dentate gyrus by three-fold, whereas afferent traced cell labeling doubled in number. Regional analysis indicated that running differentially affected specific inputs. Within the hippocampus the ratio of innervation from inhibitory interneurons and glutamatergic mossy cells to new neurons was reduced. Distal traced cells were located in sub-cortical and cortical regions, including perirhinal, entorhinal and sensory cortices. Innervation from entorhinal cortex (EC) was augmented, in proportion to the running-induced enhancement of adult neurogenesis. Within EC afferent input and short-term synaptic plasticity from lateral entorhinal cortex, considered to convey contextual information to the hippocampus was increased. Furthermore, running upregulated innervation from regions important for spatial memory and theta rhythm generation, including caudo-medial entorhinal cortex and subcortical medial septum, supra- and medial mammillary nuclei. Altogether, running may facilitate contextual, spatial and temporal information encoding by increasing adult hippocampal neurogenesis and by reorganization of new neuron circuitry.


Assuntos
Envelhecimento/fisiologia , Núcleos Cerebelares/fisiologia , Rede Nervosa/fisiologia , Neurogênese/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Corrida/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
17.
J Nucl Cardiol ; 22(2): 266-75, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25388380

RESUMO

BACKGROUND: Obesity is a common source of artifact on conventional SPECT myocardial perfusion imaging (MPI). We evaluated image quality and diagnostic performance of high-efficiency (HE) cadmium-zinc-telluride parallel-hole SPECT MPI for coronary artery disease (CAD) in obese patients. METHODS AND RESULTS: 118 consecutive obese patients at three centers (BMI 43.6 ± 8.9 kg·m(-2), range 35-79.7 kg·m(-2)) had upright/supine HE-SPECT and invasive coronary angiography > 6 months (n = 67) or low likelihood of CAD (n = 51). Stress quantitative total perfusion deficit (TPD) for upright (U-TPD), supine (S-TPD), and combined acquisitions (C-TPD) was assessed. Image quality (IQ; 5 = excellent; < 3 nondiagnostic) was compared among BMI 35-39.9 (n = 58), 40-44.9 (n = 24) and ≥45 (n = 36) groups. ROC curve area for CAD detection (≥50% stenosis) for U-TPD, S-TPD, and C-TPD were 0.80, 0.80, and 0.87, respectively. Sensitivity/specificity was 82%/57% for U-TPD, 74%/71% for S-TPD, and 80%/82% for C-TPD. C-TPD had highest specificity (P = .02). C-TPD normalcy rate was higher than U-TPD (88% vs 75%, P = .02). Mean IQ was similar among BMI 35-39.9, 40-44.9 and ≥45 groups [4.6 vs 4.4 vs 4.5, respectively (P = .6)]. No patient had a nondiagnostic stress scan. CONCLUSIONS: In obese patients, HE-SPECT MPI with dedicated parallel-hole collimation demonstrated high image quality, normalcy rate, and diagnostic accuracy for CAD by quantitative analysis of combined upright/supine acquisitions.


Assuntos
Artefatos , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Aumento da Imagem/métodos , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Compostos de Cádmio , California , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/métodos , Obesidade/complicações , Reprodutibilidade dos Testes , Compostos de Selênio , Sensibilidade e Especificidade , Transdutores , Compostos de Zinco
18.
J Strength Cond Res ; 29(6): 1465-72, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25756322

RESUMO

Current research has found conflicting results regarding the relationship between maximal oxygen uptake ((Equation is included in full-text article.)) and the repeated sprint ability (RSA) of hockey players. The purpose of this study was to use sport-specific testing methods to investigate this relationship. Forty-five (range, 18-24) college hockey players completed a graded exercise test on a skating treadmill to ascertain their (Equation is included in full-text article.). An on-ice repeated shift test was then conducted to evaluate each player's susceptibility to fatigue. First gate, second gate, and total test times were collected on the course and then used to calculate associated decrement scores. Second gate decrement was significantly correlated to (Equation is included in full-text article.)(r = -0.31, p = 0.04). Final stage completed during the graded exercise test was also significantly correlated to second gate and total decrement (r = -0.46, p = 0.001; r = -0.32, p = 0.03). No significant correlation was found between either first gate or total decrement score and (Equation is included in full-text article.)(r = -0.11, p = 0.46; r = -0.17, p = 0.26). The results of this study indicate that RSA is associated with (Equation is included in full-text article.)and final stage completed when using sport-specific testing methods.


Assuntos
Teste de Esforço/métodos , Tolerância ao Exercício/fisiologia , Hóquei/fisiologia , Consumo de Oxigênio , Patinação/fisiologia , Adolescente , Humanos , Masculino , Adulto Jovem
19.
J Athl Train ; 59(2): 159-172, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37071550

RESUMO

OBJECTIVE: To investigate whether lower limb strength is reduced in people with patellar tendinopathy (PT) compared with asymptomatic control individuals or the asymptomatic contralateral limb. DATA SOURCES: MEDLINE, PubMed, Scopus, and Web of Science. STUDY SELECTION: To be included in the systematic review and meta-analysis, studies were required to be peer reviewed, published in the English language, and case control investigations; include participants with a clinical diagnosis of PT and an asymptomatic control or contralateral limb group; and include an objective measure of lower limb maximal strength. DATA EXTRACTION: We extracted descriptive statistics for maximal strength for the symptomatic and asymptomatic limbs of individuals with PT and the limb(s) of the asymptomatic control group, inferential statistics for between-groups differences, participant characteristics, and details of the strength-testing protocol. The risk of bias was assessed using the Joanna Briggs Institute critical appraisal tool for analytical cross-sectional studies. DATA SYNTHESIS: Of the 23 included studies, 21 reported knee strength, 3 reported hip strength, and 1 reported ankle strength. Random-effects models (Hedges g) were used to calculate the pooled effect sizes (ESs) of muscle strength according to the direction of joint movement and type of contraction. The pooled ESs (95% CI) for maximal voluntary isometric contraction knee-extension strength, concentric knee-extension strength, and concentric knee-flexion strength were 0.54 (0.27, 0.80), 0.78 (0.30, 1.33), and 0.41 (0.04, 0.78), respectively, with all favoring greater strength in the asymptomatic control group. Researchers of 2 studies described maximal eccentric knee-extensor strength with no differences between the PT and asymptomatic control groups. In 3 studies, researchers measured maximal hip strength (abduction, extension, and external rotation), and all within-study ESs favored greater strength in the asymptomatic control group. CONCLUSIONS: Isometric and concentric knee-extensor strength are reduced in people with PT compared with asymptomatic control individuals. In contrast, evidence for reduced eccentric knee-extension strength in people with PT compared with asymptomatic control individuals is limited and inconsistent. Although evidence is emerging that both knee-flexion and hip strength may be reduced in people with PT, more examination is needed to confirm this observation.


Assuntos
Extremidade Inferior , Tendinopatia , Humanos , Estudos Transversais , Extremidade Inferior/fisiologia , Joelho/fisiologia , Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia
20.
Sports Biomech ; 22(3): 351-387, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36214324

RESUMO

This review aimed to synthesise the methods for assessing and reporting footwear characteristics among studies evaluating the effect of footwear on running biomechanics. Electronic searches of Scopus®, EBSCO, PubMed®, ScienceDirect®, and Web of Science® were performed to identify original research articles of the effect of running footwear on running biomechanics published from 1st January 2015 to 7th October 2020. Risk of bias among included studies was not assessed. Results were presented via narrative synthesis. Eligible studies compared the effect of two or more footwear conditions in adult runners on a biomechanical parameter. Eighty-seven articles were included and data from 242 individual footwear were extracted. Predominantly, studies reported footwear taxonomy (i.e., classification) and manufacturer information, however omitted detail regarding the technical specifications of running footwear and did not use validated footwear reporting tools. There is inconsistency among contemporary studies in the methods by which footwear characteristics are assessed and reported. These findings point towards a need for consensus regarding the reporting of these characteristics within biomechanical studies to facilitate the conduct of systematic reviews and meta-analyses pertaining to the effect of running footwear on running biomechanics.


Assuntos
Corrida , Sapatos , Adulto , Humanos , Fenômenos Biomecânicos , Revisões Sistemáticas como Assunto , Projetos de Pesquisa
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa