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1.
J Sports Sci ; 39(18): 2080-2086, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33906585

RESUMO

Athletes physically overload to improve performance. Unbalanced stress/recovery may induce overtraining, which is difficult to diagnosis as no diagnostic marker exists. Hormonal responses to a 55/80 cycle (30-min of alternating blocks of 1-min at 55% and 4-min at 80% maximum work rate) may highlight early-stage overtraining (overreaching), as blunted cortisol and testosterone responses to 55/80 follows intensified training. However, the reliability of hormonal responses to 55/80 when not overreached is unknown. Therefore, reported blunted hormonal responses could be due to inconsistent cortisol and testosterone responses to 55/80. Participants (n = 23) completed three 55/80 bouts, >7 days apart, with no exercise 24 h pre-trials. Pre-exercise urine osmolality and stress questionnaire responses were measured. Pre, post, and 30-min post-exercise saliva samples were collected for cortisol and testosterone assessment. Salivary cortisol and testosterone responses, osmolality and well-being were not different between trials. Salivary cortisol and testosterone elevated from pre- to post-exercise [by 4.2 nmol.L-1 (cortisol) and 307 pmol.L-1 (testosterone)], and 30 min post-exercise [by 160 pmol.L-1 (testosterone) only]. Intraclass correlation coefficients for pre to peak post-exercise cortisol (0.89; good) and testosterone (0.53; moderate) were calculated. This demonstrates that 55/80 induces reliable elevations of salivary cortisol and testosterone when in a healthy state.


Assuntos
Ciclismo/fisiologia , Hidrocortisona/metabolismo , Resistência Física/fisiologia , Testosterona/metabolismo , Adolescente , Adulto , Teste de Esforço , Voluntários Saudáveis , Humanos , Masculino , Reprodutibilidade dos Testes , Saliva/química , Inquéritos e Questionários , Adulto Jovem
2.
Br J Sports Med ; 55(8): 416, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33097528

RESUMO

Football is a global game which is constantly evolving, showing substantial increases in physical and technical demands. Nutrition plays a valuable integrated role in optimising performance of elite players during training and match-play, and maintaining their overall health throughout the season. An evidence-based approach to nutrition emphasising, a 'food first' philosophy (ie, food over supplements), is fundamental to ensure effective player support. This requires relevant scientific evidence to be applied according to the constraints of what is practical and feasible in the football setting. The science underpinning sports nutrition is evolving fast, and practitioners must be alert to new developments. In response to these developments, the Union of European Football Associations (UEFA) has gathered experts in applied sports nutrition research as well as practitioners working with elite football clubs and national associations/federations to issue an expert statement on a range of topics relevant to elite football nutrition: (1) match day nutrition, (2) training day nutrition, (3) body composition, (4) stressful environments and travel, (5) cultural diversity and dietary considerations, (6) dietary supplements, (7) rehabilitation, (8) referees and (9) junior high-level players. The expert group provide a narrative synthesis of the scientific background relating to these topics based on their knowledge and experience of the scientific research literature, as well as practical experience of applying knowledge within an elite sports setting. Our intention is to provide readers with content to help drive their own practical recommendations. In addition, to provide guidance to applied researchers where to focus future efforts.


Assuntos
Desempenho Atlético/fisiologia , Dieta Saudável , Política Nutricional , Futebol/fisiologia , Traumatismos em Atletas/reabilitação , Composição Corporal , Comportamento Competitivo/fisiologia , Diversidade Cultural , Suplementos Nutricionais , Meio Ambiente , Feminino , Humanos , Masculino , Necessidades Nutricionais , Condicionamento Físico Humano/fisiologia , Viagem
3.
J Int Soc Sports Nutr ; 17(1): 24, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398103

RESUMO

The microorganisms in the gastrointestinal tract play a significant role in nutrient uptake, vitamin synthesis, energy harvest, inflammatory modulation, and host immune response, collectively contributing to human health. Important factors such as age, birth method, antibiotic use, and diet have been established as formative factors that shape the gut microbiota. Yet, less described is the role that exercise plays, particularly how associated factors and stressors, such as sport/exercise-specific diet, environment, and their interactions, may influence the gut microbiota. In particular, high-level athletes offer remarkable physiology and metabolism (including muscular strength/power, aerobic capacity, energy expenditure, and heat production) compared to sedentary individuals, and provide unique insight in gut microbiota research. In addition, the gut microbiota with its ability to harvest energy, modulate the immune system, and influence gastrointestinal health, likely plays an important role in athlete health, wellbeing, and sports performance. Therefore, understanding the mechanisms in which the gut microbiota could play in the role of influencing athletic performance is of considerable interest to athletes who work to improve their results in competition as well as reduce recovery time during training. Ultimately this research is expected to extend beyond athletics as understanding optimal fitness has applications for overall health and wellness in larger communities. Therefore, the purpose of this narrative review is to summarize current knowledge of the athletic gut microbiota and the factors that shape it. Exercise, associated dietary factors, and the athletic classification promote a more "health-associated" gut microbiota. Such features include a higher abundance of health-promoting bacterial species, increased microbial diversity, functional metabolic capacity, and microbial-associated metabolites, stimulation of bacterial abundance that can modulate mucosal immunity, and improved gastrointestinal barrier function.


Assuntos
Desempenho Atlético/fisiologia , Dieta , Exercício Físico/fisiologia , Microbioma Gastrointestinal/fisiologia , Humanos , Fenômenos Fisiológicos da Nutrição Esportiva
4.
Nat Commun ; 11(1): 750, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029729

RESUMO

Facile C-C bond formation is essential to the formation of long hydrocarbon chains in Fischer-Tropsch synthesis. Various chain growth mechanisms have been proposed previously, but spectroscopic identification of surface intermediates involved in C-C bond formation is scarce. We here show that the high CO coverage typical of Fischer-Tropsch synthesis affects the reaction pathways of C2Hx adsorbates on a Co(0001) model catalyst and promote C-C bond formation. In-situ high resolution x-ray photoelectron spectroscopy shows that a high CO coverage promotes transformation of C2Hx adsorbates into the ethylidyne form, which subsequently dimerizes to 2-butyne. The observed reaction sequence provides a mechanistic explanation for CO-induced ethylene dimerization on supported cobalt catalysts. For Fischer-Tropsch synthesis we propose that C-C bond formation on the close-packed terraces of a cobalt nanoparticle occurs via methylidyne (CH) insertion into long chain alkylidyne intermediates, the latter being stabilized by the high surface coverage under reaction conditions.

5.
J Int Soc Sports Nutr ; 16(1): 62, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31864419

RESUMO

Position statement: The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the mechanisms and use of probiotic supplementation to optimize the health, performance, and recovery of athletes. Based on the current available literature, the conclusions of the ISSN are as follows: 1)Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host (FAO/WHO).2)Probiotic administration has been linked to a multitude of health benefits, with gut and immune health being the most researched applications.3)Despite the existence of shared, core mechanisms for probiotic function, health benefits of probiotics are strain- and dose-dependent.4)Athletes have varying gut microbiota compositions that appear to reflect the activity level of the host in comparison to sedentary people, with the differences linked primarily to the volume of exercise and amount of protein consumption. Whether differences in gut microbiota composition affect probiotic efficacy is unknown.5)The main function of the gut is to digest food and absorb nutrients. In athletic populations, certain probiotics strains can increase absorption of key nutrients such as amino acids from protein, and affect the pharmacology and physiological properties of multiple food components.6)Immune depression in athletes worsens with excessive training load, psychological stress, disturbed sleep, and environmental extremes, all of which can contribute to an increased risk of respiratory tract infections. In certain situations, including exposure to crowds, foreign travel and poor hygiene at home, and training or competition venues, athletes' exposure to pathogens may be elevated leading to increased rates of infections. Approximately 70% of the immune system is located in the gut and probiotic supplementation has been shown to promote a healthy immune response. In an athletic population, specific probiotic strains can reduce the number of episodes, severity and duration of upper respiratory tract infections.7)Intense, prolonged exercise, especially in the heat, has been shown to increase gut permeability which potentially can result in systemic toxemia. Specific probiotic strains can improve the integrity of the gut-barrier function in athletes.8)Administration of selected anti-inflammatory probiotic strains have been linked to improved recovery from muscle-damaging exercise.9)The minimal effective dose and method of administration (potency per serving, single vs. split dose, delivery form) of a specific probiotic strain depends on validation studies for this particular strain. Products that contain probiotics must include the genus, species, and strain of each live microorganism on its label as well as the total estimated quantity of each probiotic strain at the end of the product's shelf life, as measured by colony forming units (CFU) or live cells.10)Preclinical and early human research has shown potential probiotic benefits relevant to an athletic population that include improved body composition and lean body mass, normalizing age-related declines in testosterone levels, reductions in cortisol levels indicating improved responses to a physical or mental stressor, reduction of exercise-induced lactate, and increased neurotransmitter synthesis, cognition and mood. However, these potential benefits require validation in more rigorous human studies and in an athletic population.


Assuntos
Probióticos , Ciências da Nutrição e do Esporte , Atletas , Desempenho Atlético , Composição Corporal , Exercício Físico , Microbioma Gastrointestinal , Humanos , Sociedades Médicas
6.
Curr Treat Options Gastroenterol ; 17(3): 378-393, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31327146

RESUMO

PURPOSE OF THE REVIEW: Liver disease, colon cancer, and the gut microbiome are intimately interrelated; however, the connections linking liver disease and colorectal neoplasia via the gut microbiota remain poorly understood and rarely addressed in a single space. The goal of this review is to take a broad perspective on the clinical problem of colorectal neoplasia in the liver disease population, recognize the significance of the clinical study findings, and delve into the evidence supporting putative molecular mechanisms connecting dysbiosis in the progression of liver disease to the development of colorectal neoplasia. RECENT FINDINGS: Clinical studies have recently reported increased risk of colorectal neoplasia in patients with fatty liver disease, and risk increases with liver disease severity. Concurrently, the evolution of -omics technology has shown dysregulation of the gut microbial community, termed dysbiosis, in the progression of liver disease. Specific microbes enriched in the gut flora of liver disease patients have been linked to colon cancer and adenomatous precursor lesions. The gut microbiome of liver disease patients generates a pro-neoplastic environment, mediated via altered bile acid signaling and a dysregulated inflammatory response that suppresses immune surveillance. Research focused on the mechanisms linking liver disease to colorectal neoplasia via the gut microbiome is needed to help us prepare for the rising tide of colon cancer in young patients with an increasing prevalence of liver disease.

7.
Otol Neurotol ; 40(7): e704-e712, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31295202

RESUMO

OBJECTIVES: To undertake a large-scale review of otogenic intracranial sepsis in an area of highly prevalent HIV and tuberculosis (TB) to re-examine and inform early diagnosis and treatment efforts. METHODS: Seventy-seven consecutive cases of otogenic intracranial sepsis in KwaZulu-Natal, South Africa were reviewed for demographics, presentation, imaging, HIV status, culture results, and outcomes. RESULTS: The most common intracranial complications were intracranial abscess (46.8%), hydrocephalus (31.2%), subdural empyema (28.6%), and epidural empyema (26.0%). Ear discharge (87.0%), postauricular abscess (29.9%), and hearing loss (29.9%) were notable presenting symptoms. Overall mortality was 15.6%. Of the 45.5% of patients with HIV testing, 54.2% were HIV+, Mortality among HIV+ patients was 15.8% but only 6.3% in HIV- patients (p = 0.61, OR = 2.8). Eight patients (10.4%) had culture or histological evidence of TB infection. CONCLUSIONS: Otogenic intracranial complications continue to present late and are associated with significant mortality and morbidity, despite advances in diagnostic and treatment modalities. This study represents one of the largest case-series in the literature, and the first to specifically evaluate the effects of HIV and TB infection.Patient presentation and severity of illness varied; however, a majority of patients presented with ear discharge and no focal neurological signs. An effect size for higher mortality among HIV+ patients compared with HIV- patients was noted but was not significant. Tuberculosis infection was prevalent compared with previous studies.This study reinforces the need for enhanced screening and early treatment of ear disease to minimize associated mortality and morbidity, particularly in immunocompromised patients.


Assuntos
Abscesso Encefálico , Otopatias/etiologia , Infecções por HIV/complicações , Sepse/etiologia , Tuberculose/complicações , Adulto , Abscesso Encefálico/diagnóstico , Abscesso Encefálico/etiologia , Otopatias/diagnóstico , Feminino , Humanos , Masculino , Estudos Retrospectivos , Sepse/diagnóstico , África do Sul , Adulto Jovem
8.
Science ; 363(6423): 155-157, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-30630927

RESUMO

The classic system that describes weakly activated dissociation in heterogeneous catalysis has been explained by two dynamical models that are fundamentally at odds. Whereas one model for hydrogen dissociation on platinum(111) invokes a preequilibrium and diffusion toward defects, the other is based on direct and local reaction. We resolve this dispute by quantifying site-specific reactivity using a curved platinum single-crystal surface. Reactivity is step-type dependent and varies linearly with step density. Only the model that relies on localized dissociation is consistent with our results. Our approach provides absolute, site-specific reaction cross sections.

9.
Appl Opt ; 57(22): E1-E5, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30117913

RESUMO

We report on a 2.051 µm InxGaAs/InP-based discrete mode laser diode monolithically integrated with a curved tapered semiconductor optical amplifier for CO2 sensing applications. At a heat-sink temperature of 0°C, the laser emits a record InP value of more than 35 mW continuous-wave output power in a single longitudinal mode.

10.
Am J Gastroenterol ; 113(10): 1516-1523, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29453383

RESUMO

BACKGROUND: Hyperbaric oxygen therapy (HBOT) markedly increases tissue oxygen delivery. Case series suggest it may have a potential therapeutic benefit in ulcerative colitis (UC). We investigated the therapeutic potential of HBOT as an adjunct to steroids for UC flares requiring hospitalization. METHODS: The study was terminated early due to poor recruitment with 18 of the planned 70 patients enrolled. UC patients hospitalized for moderate-severe flares (Mayo score ≥6, endoscopic sub-score ≥2) were block randomized to steroids + daily HBOT (n = 10) or steroids + daily sham hyperbaric air (n = 8). Patients were blinded to study assignment, and assessments were performed by a blinded gastroenterologist. Primary outcome was the clinical remission rate at study day 5 (partial Mayo score ≤2 with no sub-score >1). Key secondary outcomes were: clinical response (reduction in partial Mayo score ≥2, rectal bleeding sub-score of 0-1) and progression to second-line therapy (colectomy or biologic therapy) during the hospitalization. RESULTS: A significantly higher proportion of HBOT-treated patients achieved clinical remission at study day 5 and 10 (50 vs. 0%, p = 0.04). HBOT-treated patients less often required progression to second-line therapy during the hospitalization (10 vs. 63%, p = 0.04). The proportion requiring in-hospital colectomy specifically as second-line therapy for medically refractory UC was lower in the HBOT group compared to sham (0 vs. 38%, p = 0.07). There were no serious adverse events. CONCLUSION: In this small, proof-of-concept, phase 2A trial, the use of HBOT as an adjunctive therapy to steroids for UC patients hospitalized for moderate-severe flares resulted in higher rates of clinical remission, and a reduction in rates of progression to second-line therapy during the hospitalization. Larger well-powered trials are needed, however, to provided definitive evidence of therapeutic benefit.


Assuntos
Produtos Biológicos/administração & dosagem , Colectomia/estatística & dados numéricos , Colite Ulcerativa/terapia , Glucocorticoides/administração & dosagem , Oxigenoterapia Hiperbárica/efeitos adversos , Adulto , Colite Ulcerativa/diagnóstico , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Progressão da Doença , Método Duplo-Cego , Resistência a Medicamentos , Feminino , Hemorragia Gastrointestinal , Glucocorticoides/efeitos adversos , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudo de Prova de Conceito , Indução de Remissão/métodos , Índice de Gravidade de Doença , Exacerbação dos Sintomas , Resultado do Tratamento , Adulto Jovem
11.
Physiol Behav ; 188: 181-187, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29427565

RESUMO

Periods of short-term intensified training (IT) are often used by athletes during training cycles over the season and undergoing phases of increased physical stress may impact upon the immune system. This study investigated the effects of a period of IT on free light chains (FLCs) in saliva - an emerging immune biomarker of oral inflammation - and matched serum samples in well-trained athletes. It also examined if IT influences basal FLC levels and FLC flux during acute exercise. Highly trained male cyclists (n = 10) underwent a 9-day period of IT; before and after IT participants performed a 1 h time trial (TT) on a cycle ergometer, with blood and saliva samples collected pre- and post-exercise. FLCs were assessed in serum and saliva, and IgG, IgA, IgM and creatinine were also measured in serum. Weekly training volume increased by 143% (95% CI 114-172%), p < 0.001, during IT compared with pre-trial baseline training. Following IT, the cyclists demonstrated higher salivary FLC levels. Both salivary lambda FLC concentrations (p < 0.05, η2 = 0.384) and secretion rates, and kappa FLC concentrations and secretion rates increased after IT. Salivary FLCs concentration and secretion rates decreased in response to the TT following IT (p < 0.05, η2 = 0.387-0.428), but not in response to the TT prior to IT. No significant effects of IT on serum FLCs were observed. There were no significant changes in serum FLCs in response to the TT, before or after the IT period, nor did IT impact upon other serological responses to the TT. In conclusion, IT increased basal salivary FLC parameters and amplified decreases in salivary FLCs in response to acute exercise. Increases in salivary FLC concentration likely reflects alterations to oral inflammation during times of heavy training, and we show for the first time that FLCs may have utility as a marker of exercise stress and oral health status.


Assuntos
Ciclismo/fisiologia , Treino Aeróbico/efeitos adversos , Cadeias Leves de Imunoglobulina/metabolismo , Saliva/química , Estomatite/etiologia , Ensino , Adulto , Análise de Variância , Sangue/metabolismo , Creatinina/sangue , Creatinina/metabolismo , Feminino , Humanos , Masculino , Saliva/imunologia , Fatores de Tempo , Adulto Jovem
12.
Gastroenterology ; 153(6): 1687-1689, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29100850
13.
Pract Neurol ; 17(3): 218-221, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28242629

RESUMO

The combination of tongue hemianaesthesia, dysgeusia, dysarthria and dysphagia suggests the involvement of multiple cranial nerves. We present a case with sudden onset of these symptoms immediately following wisdom tooth extraction and highlight the clinical features that allowed localisation of the lesion to a focal, iatrogenic injury of the lingual nerve and adjacent styloglossus muscle.


Assuntos
Traumatismos do Nervo Lingual/etiologia , Doenças Musculares/etiologia , Complicações Pós-Operatórias/etiologia , Língua/inervação , Extração Dentária/efeitos adversos , Doenças dos Nervos Cranianos/fisiopatologia , Feminino , Humanos , Dente Serotino/cirurgia , Língua/patologia , Adulto Jovem
14.
Exerc Immunol Rev ; 23: 8-50, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28224969

RESUMO

In this consensus statement on immunonutrition and exercise, a panel of knowledgeable contributors from across the globe provides a consensus of updated science, including the background, the aspects for which a consensus actually exists, the controversies and, when possible, suggested directions for future research.


Assuntos
Exercício Físico , Sistema Imunitário/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva , Aminoácidos/imunologia , Biomarcadores , Carboidratos da Dieta/imunologia , Ácidos Graxos/imunologia , Humanos , Inflamação/imunologia , Necessidades Nutricionais
15.
Clin Exp Optom ; 100(6): 633-641, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28147451

RESUMO

BACKGROUND: Older adults with visual loss have high rates of depression, restricted participation and reduced quality of life. We sought to measure the impact of lessons in the Alexander technique on vision-related emotional and social well-being, as secondary outcomes to a study on improving physical functioning in this population. METHODS: This is a single-blind randomised controlled trial. One hundred and twenty community-dwelling adults aged 50 to 90 years with visual impairments were randomised to either 12 Alexander lessons over 12 weeks and usual care or usual care. The Perceived Visual Ability Scale, the Keele Assessment of Participation, the emotional subscale of the Impact of Vision Impairment Profile, the Positive and Negative Affect Scale and the five-item Geriatric Depression Scale were administered at baseline and three and 12 months. Participants were receiving services from Guide Dogs NSW/ACT. RESULTS: None of the validated questionnaires found statistically significant improvements after adjustment for baseline at three or 12 months, although the emotional subscale of the Impact of Vision Impairment approached significance in favour of the intervention group (4.54 points, 95 per cent CI: -0.14 to 9.21, p = 0.06). Depressive symptoms were prevalent and associated with greater impact of visual impairment on emotional well-being (odds ratio: 1.12, 95 per cent CI: 1.07 to 1.17, p < 0.0001). Faster gait, an indicator of general mobility, was associated with less depressive symptoms (odds ratio: 1.27, 95 per cent CI: 1.06 to 1.54, p = 0.01). CONCLUSION: On average, there was no significant impact of weekly lessons in the Alexander technique on social and emotional well-being, although the emotional impact of visual impairment showed a trend toward less distress in the intervention group. Our data found that emotional distress associated with visual impairment influences depressive symptoms but contrary to expectations, the level of social support received was not significant. Additionally, gait speed is a significant predictor of depressive symptoms, suggesting that general mobility is of importance to the well-being of older adults with visual impairments.


Assuntos
Atividades Cotidianas/psicologia , Transtorno Depressivo/psicologia , Qualidade de Vida/psicologia , Seguridade Social/psicologia , Transtornos da Visão/psicologia , Pessoas com Deficiência Visual/psicologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Avaliação Geriátrica , Humanos , Masculino , Pessoa de Meia-Idade , Perfil de Impacto da Doença , Método Simples-Cego , Inquéritos e Questionários
16.
Int J Sport Nutr Exerc Metab ; 27(2): 97-104, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27710149

RESUMO

Altitude exposure can exaggerate the transient increase in markers of oxidative stress observed following acute exercise. However, these responses have not been monitored in endurance-trained cyclists at altitudes typically experienced while training. Endurance trained males (n = 12; mean (± SD) age: 28 ± 4 years, V̇O2max 63.7 ± 5.3 ml/kg/min) undertook two 75-min exercise trials at 70% relative V̇O2max; once in normoxia and once in hypobaric hypoxia, equivalent to 2000m above sea level (hypoxia). Blood samples were collected before, immediately after and 2 h postexercise to assess plasma parameters of oxidative stress (protein carbonylation (PC), thiobarbituric acid reactive substances (TBARS), total antioxidant capacity (TAC) and catalase activity (CAT)). Participants cycled at 10.5% lower power output in hypoxia vs. normoxia, with no differences in heart rate, blood lactate or rating of perceived exertion observed. PC increased and decreased immediately after exercise in hypoxia and normoxia respectively (nmol/mg/protein: Normoxia-0.3 ± 0.1, Hypoxia + 0.4 ± 0.1; both p < .05). CAT increased immediately postexercise in both trials, with the magnitude of change greater in hypoxia (nmol/min/ml: Normoxia + 12.0 ± 5.0, Hypoxia + 27.7 ± 4.8; both p < .05). CAT was elevated above baseline values at 2 h postexercise in Hypoxia only (Normoxia + 0.2 ± 2.4, Hypoxia + 18.4 ± 5.2; p < .05). No differences were observed in the changes in TBARS and TAC between hypoxia and normoxia. Trained male cyclists demonstrated a differential pattern/ timecourse of changes in markers of oxidative stress following submaximal exercise under hypoxic vs. normoxic conditions.


Assuntos
Doença da Altitude/fisiopatologia , Atletas , Desempenho Atlético , Exercício Físico , Hipóxia/etiologia , Estresse Oxidativo , Esforço Físico , Adulto , Doença da Altitude/sangue , Doença da Altitude/metabolismo , Câmaras de Exposição Atmosférica , Ciclismo , Biomarcadores/sangue , Catalase/sangue , Estudos Cross-Over , Humanos , Peroxidação de Lipídeos , Masculino , Consumo de Oxigênio , Carbonilação Proteica , Índice de Gravidade de Doença , Adulto Jovem
18.
Br J Sports Med ; 50(17): 1030-41, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27535989

RESUMO

Athletes participating in elite sports are exposed to high training loads and increasingly saturated competition calendars. Emerging evidence indicates that poor load management is a major risk factor for injury. The International Olympic Committee convened an expert group to review the scientific evidence for the relationship of load (defined broadly to include rapid changes in training and competition load, competition calendar congestion, psychological load and travel) and health outcomes in sport. We summarise the results linking load to risk of injury in athletes, and provide athletes, coaches and support staff with practical guidelines to manage load in sport. This consensus statement includes guidelines for (1) prescription of training and competition load, as well as for (2) monitoring of training, competition and psychological load, athlete well-being and injury. In the process, we identified research priorities.


Assuntos
Traumatismos em Atletas/etiologia , Transtornos Traumáticos Cumulativos/etiologia , Traumatismos em Atletas/fisiopatologia , Desempenho Atlético/fisiologia , Transtornos Traumáticos Cumulativos/fisiopatologia , Diagnóstico Precoce , Feminino , Humanos , Masculino , Educação Física e Treinamento , Guias de Prática Clínica como Assunto , Prática Profissional , Volta ao Esporte , Fatores de Risco , Medicina Esportiva , Estresse Psicológico/fisiopatologia , Estresse Psicológico/prevenção & controle , Viagem , Carga de Trabalho
19.
Br J Sports Med ; 50(17): 1043-52, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27535991

RESUMO

The modern-day athlete participating in elite sports is exposed to high training loads and increasingly saturated competition calendar. Emerging evidence indicates that inappropriate load management is a significant risk factor for acute illness and the overtraining syndrome. The IOC convened an expert group to review the scientific evidence for the relationship of load-including rapid changes in training and competition load, competition calendar congestion, psychological load and travel-and health outcomes in sport. This paper summarises the results linking load to risk of illness and overtraining in athletes, and provides athletes, coaches and support staff with practical guidelines for appropriate load management to reduce the risk of illness and overtraining in sport. These include guidelines for prescription of training and competition load, as well as for monitoring of training, competition and psychological load, athlete well-being and illness. In the process, urgent research priorities were identified.


Assuntos
Doença Aguda/epidemiologia , Traumatismos em Atletas/etiologia , Transtornos Traumáticos Cumulativos/etiologia , Carga de Trabalho , Doença Aguda/terapia , Atletas/educação , Traumatismos em Atletas/fisiopatologia , Desempenho Atlético/fisiologia , Biomarcadores/análise , Transtornos Traumáticos Cumulativos/fisiopatologia , Dieta Saudável , Medicina Baseada em Evidências , Feminino , Promoção da Saúde/métodos , Humanos , Sistema Imunitário/fisiologia , Masculino , Educação Física e Treinamento , Guias de Prática Clínica como Assunto , Prática Profissional/normas , Volta ao Esporte/fisiologia , Fatores de Risco , Medicina Esportiva , Estresse Psicológico/prevenção & controle , Terminologia como Assunto , Viagem
20.
Front Neurol ; 7: 101, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27468274

RESUMO

INTRODUCTION: Evidence is emerging for a significant clinical and neuroanatomical relationship between balance and anxiety. Research has suggested a potentially priming effect with anxiety symptoms predicting a worsening of balance function in patients with underlying balance dysfunction. We propose to show that a vestibular stimulus is responsible for an increase in state anxiety, and there is a relationship between increased state anxiety and worsening balance function. AIMS: (1) To quantify state anxiety following a vestibular stimulus in patients with a chronic vestibular deficit. (2) To determine if state anxiety during a vestibular stimulus would correlate with the severity of chronic balance symptoms and handicap. METHODS: Two separate cohorts of vestibular schwannoma (VS) patients underwent vestibular tests (electronystagmography, cervical and ocular vestibular evoked myogenic potentials, and caloric responses) and questionnaire assessments [vertigo handicap questionnaire (VHQ), vertigo symptom scale (VSS), and state-trait anxiety inventory (STAIY)]. Fifteen post-resection VS patients, with complete unilateral vestibular deafferentation, were assessed at a minimum of 6 months after surgery in Experiment 1 (Aim 1). Forty-five patients with VS in situ formed the cohort for Experiment 2 (Aim 2). Experiment 1: VS subjects (N = 15) with a complete post-resection unilateral vestibular deafferentation completed a state anxiety questionnaire before caloric assessment and again afterward with the point of maximal vertigo as the reference (Aim 1). Experiment 2: state anxiety measured at the point of maximal vertigo following a caloric assessment was compared between two groups of patients with VS in situ presenting with balance symptoms (Group 1, N = 26) and without balance symptoms (Group 2, N = 11) (Aim 2). The presence of balance symptoms was defined as having a positive score on the VSS-VER. RESULTS: In Experiment 1, a significant difference (p < 0.01) was found when comparing STAIY at baseline and at the peak of the subjective vertiginous response in post-resection patients with a unilateral vestibular deafferentation. In Experiment 2, VS in situ patients with balance symptoms had significantly worse state anxiety at the peak vertiginous response than patients without balance symptoms (p < 0.001), as did patients with a balance-related handicap (p < 0.001). CONCLUSION: Anxiety symptoms during a vestibular stimulus may contribute to a priming effect that could explain worsening balance function.

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