IMPACTOS DA ATUAÇÃO DE PROFESSORES DE EDUCAÇÃO FÍSICA DO INSTITUTO BENJAMIN CONSTANT DURANTE A PANDEMIA DA COVID-19: UM RELATO DE EXPERIÊNCIA

Este artigo apresenta o relato de experiência docente durante a pandemia da COVID-19 (março de 2020 a dezembro de 2021), no Instituto Benjamin Constant/ Rio de Janeiro. Estudo de natureza qualitativa, com características de abordagem descritiva exploratória, com emprego de técnicas da pesquisa documental/ bibliográfica, que teve o objetivo abordar as estratégias, os desafios e a superação dos professores no teletrabalho, que se reinventaram no processo de ensino-aprendizagem, baseado na teoria do ensino centrada no aprendiz, e entregaram conhecimentos diversificados de hábitos saudáveis, de alimentação e nutrição, práticas esportivas e estratégias preventivas às três etapas da Educação Básica, a partir de uma (Re)Educação Física baseada em evidências. Percebeu-se o envolvimento dos estudantes nas atividades propostas e atitudes críticas de apropriação dos conteúdos apresentados, contudo, as peculiaridades da comunidade escolar daquela instituição foram desconsideradas durante o teletrabalho (acesso às tecnologias) e no momento do retorno às atividades presenciais, com cenário pandêmico preocupante à adoção de procedimentos sanitários

Efeitos das fontes e níveis de lipídios nas dietas de ratos machos da linhagem wistar (rattus norvegicus) sobre frações lipídicas do sangue Effect of source and level of fat in the diet of wistar rats (rattus norvegicus) on lipoidal fractions in the serum

Foram estudadas quatro fontes lipídicas (óleo de soja, óleo de canola, azeite de oliva e gordura suína) em dois níveis na dieta (7 e 14%), verificando a influência do consumo dessas fontes lipídicas sobre algumas frações lipídicas do sangue de ratos. Assim, oito grupos de ratos machos da linhagem Wistar (Rattus norvegicus) foram alimentados ad libitum por 56 dias com oito dietas distintas contendo as fontes e níveis citados de lipídios. As dosagens de colesterol total e triacilgliceróis no soro foram realizadas pelo método colorimétrico/enzimático utilizando "kit" comercial específico. O colesterol em HDL foi determinado por precipitação dos quilomícrons, VLDL e LDL, utilizando também "kit" específico. O aumento de lipídios na dieta para 14% elevou os valores de colesterol total, HDL-colesterol e LDL+VLDL-colesterol séricos, quando a fonte foi a gordura suína. Com 14% de lipídios na dieta, os menores valores de triacilgliceróis séricos foram observados nas fontes lipídicas óleo de soja e canola, com valores de 76,09 e 84,42 mg/dL, respectivamente.Four fat sources (soybean oil, canola oil, olive oil, swine fat) were evaluated with regard to their influence, at two levels in the diet (7 and 14%), on some fat fractions in rats' blood. Thus, eight groups of Wistar rat (Rattus norvegicus) males were ad libitum fed eight different diets, containing the fat and level reported, for 56 days. The dosages of total serum cholesterol and thriacylglicerols were performed by the colorimetric/enzymatic method utilizing a commercial specific kit. The HDL cholesterol was determined by precipitation of kilomicra (VLDL and LDL) by utilizing also a specific kit. The increase of fat in the diet to 14% raised the total cholesterol contents, serum HDL cholesterol and LDL + VLDL cholesterol when the source was swine fat. With 14% of fat in the diet, the lowest values of serum triacylglycerols were found for the fat sources soybean and canola oils, with values of 76.09 and 84.42mg/dl, respectively

Efeito das fibras dos farelos de trigo e aveia sobre o perfil lipídico no sangue de ratos (Rattus norvegicus) wistar Effect of wheat and oat bran fibers on the lipid profile of mouse (Rattus novergicus) wistar blood samples

Com o objetivo de determinar os efeitos das fontes de fibras de farelo de aveia e trigo sobre o perfil lipídico no sangue de ratos (Rattus norvegicus) wistar, conduziu-se este ensaio utilizando-se 48 animais, os quais foram distribuídos em um delineamento ao acaso e divididos em oito grupos. Durante um período de seis dias, os animais receberam dietas padrão para se adaptarem ao experimento. Após esse período, os animais receberam dietas distintas por 63 dias, sendo elas compostas com 5, 10 e 15% de farelo de aveia e 1% de colesterol e outras três compostas por 5,10 e 15% de farelo de trigo como fonte de fibra e 1% de colesterol. Havia dois grupos-controle, sendo o primeiro isento de colesterol e com 5% de celulose como fonte de fibra e o segundo com 1% de colesterol. Após os 63 dias recebendo as dietas experimentais, os animais se submeteram às mesmas análises de colesterol, HDL, LDL, VLDL e triacilglicerol no sangue. Os ratos alimentados com farelo de aveia 5, 10 e 15% tiveram redução significativa do colesterol sérico em relação ao grupo controle contendo 1% de colesterol e aos alimentados com 1% de colesterol. Os níveis de HDL foram maiores nos grupos alimentados com 10 e 15% do farelo de aveia do que nos grupos alimentados com 5% de farelo de aveia e com farelo de trigo a 5,10 e 15%. Não houve diferença estatística em relação ao grupo controle e os alimentados com farelo de aveia 10 e 15%. A concentração de LDL apresentou-se menor no tratamento com 15% em relação ao controle contendo colesterol e aos tratamentos com farelo de trigo. Já o os níveis de triacilglicerol e VLDL foram significativamente menores nos animais alimentados com 15% dos farelos de aveia e trigo em relação a todos os outros tratamentos. Conclui-se, neste experimento, que o perfil lipídico pode ser melhorado com a adição do farelo de aveia à dieta e que o farelo de trigo exerce pouca influência apenas nos níveis de triacilglicerol séricos.<br>This work aimed to determine the effects of oat and wheat bran fibers on the lipid profile in the blood of wistar mouse (Rattus novergicus). This work used 48 animals, which were randomly distributed and divided into eight groups. During a period of six days, the animals received a pattern diet for adapting to the experiment. After this period, the animals received different diets for 63 days. The diets were composed of 5, 10, and 15% of oat bran and 1% of cholesterol. Other three diests were composed of 5, 10, and 15% of wheat bran as fiber source and 1% of cholesterol. There was two control groups, being the first exempt of cholesterol and with 5% of cellulose as fiber source, and the second having 1% of cholesterol. After 63 days feeding the experimental diets, the animals were submitted to analyses for cholesterol in the blood, HDL, LDL, VLDL, and triacylglicerol. The mice fed with oatmeal at 5, 10, and 15% presented a significant reduction of serum cholesterol relative to the control group containing 1% of cholesterol and to those fed with 1% cholesterol. The HDL levels were higher in groups fed with oatmeal and 15% of wheat meal than in those fed wheat meal at 5 and 10%. In spite of that, there was no statistical difference relative to the control groups and those fed with oat brans. The LDL concentrations were lower in the treatments with 10 and 15% relative to the control containing cholesterol and to the treatments with wheat meal. Triacylglicerol levels were significantly lower in animals fed with 15% oatmeal and wheat meal relative to all other treatments. It follows that the lipid profile may be improved with the addition of oat bran to the diet and that wheat meal influences only the levels of serum triacylglicerol

Mean and SD for power output (upper), anaerobic (middle) and aerobic (lower) mechanic power for each 200 m during the 4-km cycling TT for control (CON), low carbohydrate availability with placebo ingestion (DEP-PLA) and low carbohydrate availability with caffeine ingestion (DEP-CAF).

<p>*Significantly different between DEP-CAF and DEP-PLA (P<0.05); #Significantly different between CON and DEP-PLA (P<0.05); †Significantly different between DEP-CAF and CON (P<0.05).</p

Experimental Protocol.

<p>[La]: plasma lactate concentrations; MVC: maximal voluntary contraction; EMG: electromyographic activity; VO₂: oxygen uptake; RER: respiratory exchange ratio; HR: heart rate; PPO: power output; Paer: aerobic mechanical power output; Pan: anaerobic mechanical power output.</p

Mean and SD for lactate concentration at rest, and pre and post the 4-km cycling TT.

<p>Data are expressed in mmol.L⁻¹.</p>*<p>Significantly higher than Rest and Pre-TT (P<0.05).</p

Mean and SD for rating of perceived exertion (RPE), integrated electromyography (iEMG), average oxygen uptake (VO₂) and heart rate (HR) during the 4-km cycling TT.

<p>iEMG expressed as percentage of EMG value obtained during MVC. CON: control; DEP-PLA: low carbohydrate availability with placebo ingestion; DEP-CAF: low carbohydrate availability with caffeine ingestion.</p

Time to complete the 4-km cycling TT for control (CON), low carbohydrate availability with placebo ingestion (DEP-PLA) and low carbohydrate availability with caffeine ingestion (DEP-CAF).

<p>*Moderate effect of DEP-PLA compared to CON and DEP-CAF (ES = 0.65 and 0.94, respectively). #Small effect of DEP-CAF compared to CON (ES = 0.45). Data are expressed as mean (•) and individual (○) values.</p

Mean and SD for work total (Wtot), total aerobic (Waer) and anaerobic work (Wan) during the 4-km cycling TT for control (CON), low carbohydrate availability with placebo ingestion (DEP-PLA) and low carbohydrate availability with caffeine ingestion (DEP-CAF).

<p>*Moderate effect of DEP-PLA compared to CON (ES = 0.93). §Small and moderate effect of DEP-CAF compared to CON and DEP-PLA (ES = 0.53 and 1.18, respectively). †Small effect of DEP-PLA compared to CON (ES = 0.40). #Moderate and large effects of DEP-CAF compared to CON and DEP-PLA (ES = 0.96 and 1.33, respectively).</p

Caffeine Increases Anaerobic Work and Restores Cycling Performance following a Protocol Designed to Lower Endogenous Carbohydrate Availability

The purpose this study was to examine the effects of caffeine ingestion on performance and energy expenditure (anaerobic and aerobic contribution) during a 4-km cycling time trial (TT) performed after a carbohydrate (CHO) availability-lowering exercise protocol. After preliminary and familiarization trials, seven amateur cyclists performed three 4-km cycling TT in a double-blind, randomized and crossover design. The trials were performed either after no previous exercise (CON), or after a CHO availability-lowering exercise protocol (DEP) performed in the previous evening, followed by either placebo (DEP-PLA) or 5 mg.kg−1 of caffeine intake (DEP-CAF) 1 hour before the trial. Performance was reduced (−2.1%) in DEP-PLA vs CON (421.0±12.3 vs 412.4±9.7 s). However, performance was restored in DEP-CAF (404.6±17.1 s) compared with DEP-PLA, while no differences were found between DEP-CAF and CON. The anaerobic contribution was increased in DEP-CAF compared with both DEP-PLA and CON (67.4±14.91, 47. 3±14.6 and 55.3±14.0 W, respectively), and this was more pronounced in the first 3 km of the trial. Similarly, total anaerobic work was higher in DEP-CAF than in the other conditions. The integrated electromyographic activity, plasma lactate concentration, oxygen uptake, aerobic contribution and total aerobic work were not different between the conditions. The reduction in performance associated with low CHO availability is reversed with caffeine ingestion due to a higher anaerobic contribution, suggesting that caffeine could access an anaerobic “reserve” that is not used under normal conditions