Avaliação do estado de hidratação dos atletas, estresse térmico do ambiente e custo calórico do exercício durante sessões de treinamento em voleibol de alto nível

Sweating is the main mechanism to dissipate the heat during exercise in hot environments. Fluid replacement has been recommended to prevent the dehydration, reduction on physical performance, and hyperthermia. However, the recommendations do not quantify the metabolic cost of the activity and the thermal environmental stress in a real sport situation. This study measured the fitness level ( VO 2 peak)» heart rate (HR), energy cost (CAL), sweat rate (SR), urine volume (Vu), specific gravity (Gu), and color (Uc), and the thermal environmental conditions (WBGT) during training sessions (Straj„) in a youth volleyball team. The Strain were equivalent to a mean CAL = 650.8 ± 99.1 kcal.h' 1 (55% V 0 2peak)» with a mean HR = 133 ± 9 beat.min*1 During Strain, the mean SR = 15.1 ± 4.6 ml.min'1 (1,56 1, total), with a water ingestion ad libitum = 8.9 ± 3.7 ml.min' 1 (0,9 1, total). The mean Vu= 0.8 ± 0.4 ml.min' 1 (0.08 1 total), the Uc was classified as “2” (initial) e “3” (final). The mean Gu = 1024 ± 4 (initial) and 1026 ± 6 (final). The WBGT averaged from thermoneutral to warm (20.1 a 24.6 °C WBGT). In conclusion, the Strain were of moderate intensity and conducted in an environment classified as moderate risk for hyperthermia. The athletes finished the sessionswithin the range of 0.9% of the body mass and euhydrated in agreement with the urine specific gravity and color.A sudorese (Ts) é o principal mecanismo dissipador de calor durante o exercício em ambientes quentes. Recomenda-se a ingestão de água (H2O) suficiente para repor a perda hídrica pela sudorese e evitar os efeitos adversos da desidratação no rendimento esportivo. No entanto, as recomendações não quantificam o custo calórico (CAL) e os fatores ambientais (IBUTG) em situações esportivas reais. Este estudo mediu a capacidade aeróbica ( V 0 2PiCo)* a H20, o CAL, a freqüência cardíaca (FC), a Ts, o fluxo urinário (Vu), a coloração (Ucor) e a gravidade específica da urina (Du) e o IBUTG durante sessões de treinamento (Streino) de uma equipe juvenil (média de 18 anos) masculina de voleibol. O CAL de uma Strein0= 650 ± 99 kcal.h (55% do V 0 2Pico)> a FC média = 133 ± 9 bat.min'1 A Ts média = 15 ± 4 ml.min'1 (1,5 litros, total), com uma ingestão de água = 8,9 ± 3,7 ml.min"1 (0,9 litros total). O Vu = 0,8 ± 0,4 ml.min'1 (0,08 litros total), e a Ucor = “2” no início e “3” no final. A Du inicial = 1024 ± 4 e a final = 1026 ± 6. O IBUTG variou entre termoneutro e moderadamente quente (20,1 a 24,6 °C). Concluiu-se que, as Streino foram de intensidade moderada e o ambiente classificado como risco moderado para hipertermia. Os atletas terminaram as sessões com -0,9% da massa corporal e eu-hidratados de acordo com a gravidade específica e coloração da urina

Spectral-Domain Optical Coherence Tomography Findings in Neurofibromatosis Type 2

PURPOSE. Neurofibromatosis type 2 (NF2) is an autosomal-dominant disease, characterized by bilateral vestibular schwannomas, multiple central nervous system (CNS) tumors, skin tumors, and juvenile cataract. The present study assessed retinal abnormalities using spectraldomain optical coherence tomography (SD-OCT) in a case series of NF2 patients. METHODS. Nine NF2 patients from the neurofibromatosis outpatient reference center of the Federal University of Minas Gerais, in Brazil, were submitted to a complete anamnesis and a detailed ophthalmic evaluation, including SD-OCT, to detect retinal lesions. RESULTS. Of the nine NF2 patients evaluated, five had an early onset (<20 years) of NF2, and four patients had a late onset (>20 years) of symptoms. SD-OCT scans revealed retinal abnormalities in every patient with early onset (EOS) and in two patients with late onset (LOS) of the disease. In the EOS group, SD-OCT scans revealed flame-shaped epiretinal membranes (ERM) with peculiar characteristics in four eyes of three patients. Two patients had fine undulations of the inner retinal surface with a subtle ERM. Retinal hamartomas were present in four eyes of three patients with EOS; in two eyes, they were subclinical and were detected only by SD-OCT scans. In two patients with LOS and one patient with EOS, SD-OCT scans revealed retinal tufts of a nerve fiber layer. CONCLUSIONS. SD-OCT revealed ERM in most patients with NF2, therefore it may be a valuable exam for evaluating NF2 patients. Epiretinal membranes in NF2 has unique features, distinguishing it from idiopathic ERM or membranes associated with other diseases. We suggest that flame-shaped ERM seems to be specific for NF2 and that ERM can be considered as an important diagnostic sign of NF2

Temperature of the ingested water on fatigue during exercise until exhaustion in a thermoneutral environment

Os efeitos da ingestão de água durante o exercício em ambiente termoneutro, assim como os efeitos da temperatura da água ingerida sobre a fadiga ainda não estão bem estudados. Este trabalho foi realizado para estudar os efeitos de três diferentes temperaturas da água ingerida sobre a tolerância ao esforço submáximo de seis voluntários sadios (idade 24,0 ± 3,5 anos; peso 67,0 ± 4,8 kg; V 02pjCo 47,8 ± 9,1 mL/kg.min*1 e percentual de gordura 9,5 ± 2,0%) durante o repouso (60 min) ou durante o esforço submáximo numa bicicleta ergométrica (60% da V02PiCO) até a exaustão. As temperaturas da água foram escolhidas para produzir resfriamento corporal (10 °C), ou para simular a temperatura corporal interna (38 °C) ou constituir um ponto intermediário (24 °C). Foram medidos continuamente o consumo de oxigênio (V02), a extração de gás carbônico (VC02), a freqüência cardíaca (FC), as temperaturas retal (Tr) e média da pele (TMP), e o calor acumulado (S). O lactato plasmático (La) foi dosado antes e ao final do exercício. Em todas as situações experimentais, os indivíduos ingeriam 1320 mL de água (nas temperaturas de 10, 24 e 38 °C), assim distribuídas: 600 mL 15 minutos antes do procedimento experimental e três doses de 240 mL, aos 15, 30 e 45 minutos, do repouso ou do exercício. A temperatura e a umidade relativa do ar durante os experimentos variaram de 22,4 a 22,8 °C e 62,6 a 65%, respectivamente. O estudo seguiu o delineamento de um Quadrado Latino e a análise de variância de dois fatores (para o TTE) com medidas repetidas no segundo fator (para Tre, TMP, S, FC e V 02) seguidas do teste de Tukey (p < 0,05). A temperatura da água não afetou o tempo máximo de exercício. O exercício aumentou todas as variáveis, como esperado, mas a temperatura da água não interferiu nas respostas. No repouso, observou-se uma redução da Tre, TMP e S ao longo do tempo, sugerindo um resfriamento decorrente do repouso ou das condições térmicas do ambiente. Os resultados mostram que a temperatura da água ingerida não interferiu na temperatura corporal e na performanceThe effects of water ingestion during exercise at a thermoneutral environment and the effects of the ingested water temperature on fatigue have not been studied. This research was designed to study the effects of three different temperatures of ingested water on fatigue of six healthy male subjects (age 24.0 ± 3.5 years; weight 67.0 ± 4.8 kg; V 0 2Peak 47.8 ± 9.1 mL/kg.min'1 and body fat 9.5 ± 2.0%) during rest (60 min) or at a sub-maximal cycle ergometer exercise (60% V O 2 peak) to the exhaustion (ET). The water temperatures were chosen to produce physical cooling (10 °C), to simulate the body temperature (38 °C) and to find an intermediate point (24 °C). There were continuous measurements of oxygen uptake ( V 0 2), carbonic gas extraction (V C 0 2), heart rate (HR), rectal (Tre) and skin (Tsk) temperatures, and heat storage (S). Plasma lactate (La) was measured before and at the end of exercise. In all of the six experimental conditions the volunteers ingested 1320 mL of water (at 38 °C or 24 °C or 10 °C) following the schedule: 600 mL (15 min before) and three doses of 240 mL each at 19, 34 and 49 minutes of resting or exercise. The temperature and air relative humidity during the experiments ranged from 22.4 to 22.8 °C and 62.6 to 65% respectively. The experimental design followed a latin square model and a two-way anova (for TE) and repeated measures (for Tre, TMP, S, FC, V 0 2 and V C 0 2) with post hoc Tukey’s test was used to analyze data, with significance level of p < 0.05. The temperature of ingested water did not change the time to exhaustion. The exercise increased all variables, as expected, but the temperature of ingested water did not modify their responses. During resting, there were lower Tre, TMP, and S, suggesting an cooling effect that could be due to the resting itself or to the thermal environmental conditions. The results showed that the temperature of ingested water did not modify the body temperatures neither the time do exhaustio

Neurofibromatose tipo 1: mais comum e grave do que se imagina

OBJETIVO: Determinar a prevalência das características clínicas da neurofibromatose tipo 1 (NF1), avaliar sua gravidade e visibilidade e quantificar baixa estatura, macrocrania, força muscular e as alterações da motricidade oral e da voz nesta enfermidade. MÉTODOS: 183 pacientes atendidos no Centro de Referência em Neurofibromatose de Minas Gerais (CRNF-MG) foram avaliados quanto à frequência de manifestações clínicas e complicações da NF1. A gravidade e a visibilidade foram avaliadas com o uso de escalas de Riccardi e Ablon respectivamente. As alterações da motricidade oral e da voz foram verificadas com uso do software Vox-Metria, e a medida quantitativa da força muscular realizada com uso de dinamômetro. RESULTADOS: As manifestações clínicas habituais da NF1 observadas neste estudo são semelhantes às descritas na literatura. Entretanto, mais de 50% dos pacientes apresentaram gravidade e visibilidade moderada e grave. A incidência de macrocrania e baixa estatura foi maior nos pacientes do CRNF-MG. As alterações da voz e da motricidade oral foram pela primeira vez quantificadas, com rouquidão e distúrbios da motricidade oral observados em mais de 60% dos pacientes. A força muscular estava reduzida em 67% dos pacientes. CONCLUSÃO: O perfil clínico destes pacientes é semelhante aos relatos prévios da literatura. Mais da metade dos pacientes avaliados apresenta as formas moderada e grave da doença (gravidade e visibilidade), incluindo baixa estatura, macrocrania, distúrbios da voz e da motricidade oral e redução da força muscular. Os resultados desta pesquisa contrariam o conceito tradicional de que a NF1 é uma doença benigna e demonstram alguns aspectos clínicos, ainda não descritos na literatura.OBJECTIVE: To study prevalence of clinical features among Brazilian patients diagnosed with neurofibromatosis type 1(NF1), comparing these features with international data to evaluate the severity and visibility of the disease and quantify less frequent manifestations such as short stature, macrocephaly, muscle strength, voice abnormalities and oral motor disorders. METHODS: 183 patients diagnosed with NF1, attended at the Neurofibromatosis Outpatient Reference Center, were evaluated for clinical manifestations and complications of NF1. Severity and visibility were verified using the Riccardi and Ablon scales respectively. Voice abnormalities and oral motor disorders were quantified using the Vox-Metria software and maximal voluntary muscle strength (MVMS) was quantified using a handgrip dynamometer. RESULTS: Clinical manifestations of NF1 observed were comparable to those described in literature. However, more then 50% of patients presented severity and visibility classified as moderate and severe. The incidence of macrocephaly and short stature was higher among the Brazilian patients. Voice abnormalities and oral motor disorders were quantified for the first time, with hoarseness and oral motor disorders observed in more then 60% the patients. Maximal voluntary muscle strength was found to be reduced in 67% of patients. CONCLUSION: The main clinical features of these patients are similar to those reported in previous studies. More then one-half of the patients presented moderate and severe levels of NF1 (severity and visibility), including short stature, macrocephaly, voice abnormalities and oral motor disorders and decreased muscle strength. These results are in disagreement with the traditional concept that NF1 is a benign disease and also disclosed some clinical aspects not previously reported

Effects of carbohydrates and electrolytes on thermoregulatory responses and anaerobic performance following a prolonged exercise in the heat

Most of the energy needed for muscle contraction during the Wingate anaerobic test is derived from adenosine triphosphate, creatine phosphate and glucose breakdown. Exogenous carbohydrates contribute to the maintenance of blood glucose and that could lead to the improvement of anaerobic performance following a prolonged sub-maximal exercise (PE). The purpose of the present study was to compare the anaerobic power output of men in the Wingate test performed immediately after 90 min of cycling at 60% of the maximal workload, with and without the ingestion of carbohydrates and electrolytes (CHO), as well as the physiological responses during the PE. Seven men (21.4 ± 4.2 yrs; 65.46 ± 10.45 kg; 9.4 ± 1.8% fat and 60.38 ± 4.76 mLO2.kg-1.min-1) volunteered for the study. They received adequate amounts of distilled water and capsules containing either glucose and electrolytes (CHO) or placebo (PLA) at every 15 min, while exercising on an environmental chamber at 28 ºC temperature and 79% air relative humidity, in a double-blind protocol. Rectal temperatures and heart rates were monitored continuously. Blood glucose and lactate were also measured. Sweat rates were estimated from pre to post-exercise body weight differences, taking into account water intake and urine excretion. As expected, blood glucose was significantly higher (p ≤ 0.05) in CHO (116 ± 12mg/dL) than in PLA (81 ± 7mg/dL). Relative power output in CHO (12.63 ± 1.27 W·Kg-1) and in PLA ( 12.64 ± 1.30 W·Kg-1) as well as the total work output in CHO (18.57 ± 2.86 KJ) and in PLA (20.36 ± 6.01 KJ) were not different. Thermal regulation was also unaffected. The ingestion of CHO did not affect any of the variables under investigationCarboidratos exógenos contribuem para a manutenção da glicose sangüínea e acredita-se que isto possa melhorar o desempenho anaeróbio após um exercício prolongado. Foram objetivos deste estudo comparar a potência máxima e o trabalho total de atletas, no teste anaeróbio de Wingate realizado após 90 min de exercício prolongado (EP), com e sem a ingestão de mistura eletrolítica carboidratada (MEC), bem como as respostas termorregulatórias ocorridas durante o EP. Sete homens (21,4 ± 4,2 anos; 65,46 ± 10,45 kg; 9,4 ± 1,8% de gordura e 60,38 ± 4,76 mLO2·kg-1·min-1) ingeriram água destilada e cápsulas gelatinosas contendo MEC ou placebo (PLA) a cada 15 min, enquanto realizavam o EP a 60% da carga máxima em uma câmara ambiental (25,9 IBUTG), em duplo-velado. Temperatura retal, freqüência cardíaca, lactato e glicose sangüínea foram medidas. Como era esperado, a glicose sangüínea foi mais alta (p≤0,05) quando a ingestão da MEC (116 ± 12 mg.dL-1) foi comparada à ingestão de PLA (81±7mg/dL). Não houve diferença entre as situações MEC e PLA na termorregulação, na potência relativa (12,63 ± 1,27 W·Kg-1 e 12,64 ± 1,30 W·Kg-1, respectivamente) ou no trabalho total (18,57 ± 2,86 KJ e 20,36 ± 6,01 KJ, respectivamente). Conclusões: A ingestão da MEC não alterou nenhuma das demais variáveis estudada

Publishing more, or better? The olympic anteater

O presente texto discute alguns dos critérios que os órgãos financiadores da pesquisa utilizam para escolher os projetos contemplados nas ciências do esporte, embora essa questão seja importante também para os cientistas brasileiros de outros campos do conhecimento. Observa-se que as transformações realizadas nos últimos anos nos sistemas de fomento e classificação dos programas de pós-graduação resultaram no aumento da produtividade científica brasileira medida pelas publicações indexadas no contexto internacional. No entanto, a pressão institucional quantitativa pela publicação pode estar induzindo a graves distorções de comportamento entre os cientistas, o que compromete o próprio sentido do fazer científico e o futuro da ciência no Brasil. Uma comparação entre o tamanduá e a ciência produzida pelos brasileiros pode ser útil no entendimento de algumas propostas de ação para a comunidade científica ligada às ciências do esporte.The present text issues some of the research funding institutions criteria used to approve sports science projects, although it seems to be an interesting and common problem to Brazilian scientists of another scientific areas. It has been observed that the performed changes in the postgraduate supporting and qualifying system have resulted in a greater Brazilian scientific productivity, as shown by its indexed international papers. Nevertheless, the institutional pressure for quantitative publishing could be resulting in behavioral distortions of the researchers, which could be harmful to the scientific practice and the science future in Brazil. A comparison is made between the anteater and the produced science of Brazilians and it seems to be useful to clarify some possible political actions to the sports science scientific community.Cet article examine certains des critères utilisées par des organismes de financement de la recherche pour choisir les projets envisagés en sciences du sport. Cette question est également importante pour les scientifiques brésiliens dans d'autres domaines de la connaissance. On observe que les modifications apportées ces dernières années dans les systèmes de promotion et de classement des programmes d'études supérieures ont conduit à l'augmentation de la productivité scientifique au Brésil selon ce qui est mesuré dans le contexte international par les publications indexées. Cependant, cette pression quantitative de publication peut être induisant une distorsion grave de comportement parmi les scientifiques. Cela mine le sens même du travail scientifique et l'avenir de la science au Brésil. Une comparaison de fourmilier et les travaux scientifiques produits par les Brésiliens peut être utiles pour comprendre quelques propositions d'action à la communauté scientifique liée à la science du sport.El texto aquí elaborado discute algunos de los criterios que las instituciones de investigación científica utilizan para seleccionar los proyectos que serán favorecidos en las ciencias del deporte, aunque esta situación sea importante también para los científicos brasileños de otros campos del conocimiento. Se observa que las transformaciones realizadas en los últimos años en los sistemas de fomento y clasificación de los programas de postgrado resultaron en un aumento de la productividad científica brasileña conforme medido por las publicaciones indexadas en el contexto internacional. Sin embargo, la presión institucional cuantitativa para publicación puede estar induciendo a graves distorsiones de comportamiento entre los científicos, lo que compromete el propio sentido de la actividad científica y el futuro de la ciencia en Brasil. Una comparación entre el oso hormiguero y la ciencia que se produce por los brasileños puede ser útil en el entendimiento de algunas proposiciones de acción para la comunidad científica relacionada a las ciencias del deporte

Assessment of functional capacity through oxygen consumption in patients with asymptomatic probable heart disease

PURPOSE: To compare peak exercise oxygen consumption (VO2peak) of healthy individuals with asymptomatic individuals with probable heart disease. METHODS: Ninety-eight men were evaluated. They were divided into two groups: 1) 39 healthy individuals (group N) with an age range of 50±4.6 years; and 2) 59 asymptomatic individuals with signs of atherosclerotic and/or hypertensive heart disease (group C) with an age range of 51.9±10.4 years. In regard to age, height, body surface area, percentage of fat, lean body mass, and daily physical activity, both groups were statistically similar. Environmental conditions during the ergometric test were also controlled. RESULTS: Maximal aerobic power (watts), VO2peak, maximal heart rate, and maximal pulmonary ventilation were lower in group C (p<0.01) than in group N; weight, however, was lower in group N (p=0.031) than in group C. Differences in the respiratory gas exchange index, heart rate at rest, and the maximal double product of the two groups were not statistically significant. CONCLUSION: Signs of probable heart disease, even though asymptomatic, may reduce the functional capacity, perhaps due to the lower maximal cardiac output and/or muscle metabolic changes