Effect of Menstrual Cycle Phase on Fuel Oxidation Post HIT in Women Reproductive Age: A Pilot Study.

Women of childbearing age have variations in substrate oxidation rates that can lead to overweight, type II diabetes, and other conditions that may be associated with metabolic inflexibility and the variations in estrogen concentrations observed during the monthly ovarian cycle. PURPOSE: This study aimed to verify and compare the influence of eight treadmill high-intensity interval training (HIT) sessions on carbohydrate and lipid oxidation rates (CHOox and LIPox, respectively) and intensities of ventilatory anaerobic thresholds (VATs) of women in different phases of the monthly ovarian cycle. METHODS: Eleven irregularly active women performed incremental treadmill exercise testing followed by submaximal work-rate running for 45 min to determine VATs, VO2peak, peak velocity (Vpeak), and substrate oxidation rates, before and after a training period, in different phases of their monthly ovarian cycle (follicular phase group, FL, n = 6; luteal phase group, LT, n = 5). The training period consisted of eight HIT sessions, composed each one of eight sets of 60 s running at 100%Vpeak interspersed by 75 s recovery every 48 h. RESULTS: Our results showed no significant differences in VATs intensities between groups. The comparison between groups showed significant differences in relative energy derived from CHO pre- and post-training of -61.42% and -59.26%, respectively, and LIP pre- and post-training of 27.46% and 34.41%, respectively. The relative energy derived from CHO after the training period was 18.89% and 25.50% higher for FL and LT, respectively; consequently, the relative energy derived from LIPox after the training period was 8,45% and 3.46% lower for FL and LT, respectively. Over the training period, Vpeak was ~13.5 km/h, which produced the relative intensities of ~89%VO2peak e ~93%HRpeak for both groups. CONCLUSION: The monthly ovarian cycle phases promote significant changes in substrate oxidation rates leading to a decrease in CHOox. High-intensity interval training can minimize the differences observed and constitute an alternative intervention.

Six HIT Sessions Improve Cardiorespiratory Fitness and Metabolic Flexibility in Insulin Resistant and Insulin Sensitive Adolescents with Obesity.

To evaluate the effect of high-intensity interval training (HIT) on the cardiorespiratory performance and substrate oxidation pattern in insulin-resistant and insulin-sensitive obese adolescents. METHODS: We recruited 25 obese adolescents in three schools, and trained them in six HIT sessions, comprising of six series at 100% and recovery at 50% peak velocity (Vpeak). For the evaluation, the participants were divided into two groups: insulin-resistant (IR, n = 12; HOMA index ≥3.16) and insulin-sensitive (IS, n = 13). All participants underwent cardiopulmonary and indirect calorimetry testing. We compared the effects of HIT before and after the intervention among the two groups. The data were analyzed using Student's t and Mann-Whitney (intergroup comparisons) and Student's t and Wilcoxon (pre- and post-training comparisons) tests; and Cohen's d (influence of HIT). RESULTS: There was a significant post-training increase in Vpeak, oxygen consumption (VO2), velocity (V), and heart rate (HR) at the exertion intensity at the first ventilatory anaerobic threshold (VAT1) in both groups (p < 0.05; d < 0.02). The exercise promoted changes in substrate oxidation rates of the groups, with an increase in carbohydrate oxidation (CHOox) for both IR (p = 0.064) and IS (p = 0.034). CONCLUSION: Six HIT sessions improved cardiorespiratory performance in both groups and increased CHOox in insulin-sensitive obese adolescents, suggesting its utility for increasing physical fitness and controlling glycemia in these population groups.

Equações de força muscular respiratória de crianças e adolescentes / Respiratory muscle strength equations in children and adolescents / Ecuaciones de la fuerza de los músculos respiratorios en niños y adolescentes

Objetivo: Revisar as equações de predição para a força muscular respiratória em crianças e adolescentes e identificar as variáveis independentes com maior poder preditivo para força muscular respiratória. Métodos: Foi realizada revisão sistemática nas bases de dados: PEDro, MedLine/ PubMed, Cochrane Library, LILACS/ BVS Library, SciELO e Google Acadêmico. Foram incluídos artigos com crianças e adolescentes, publicados entre 2009 a 2019, nos idiomas português, inglês e espanhol, cujo método de avaliação utilizou-se da manovacuometria e equações preditivas foram propostas. Foram excluídos estudos que não estavam disponíveis na íntegra, duplicados ou com baixa qualidade metodológica (Escala PEDro <5,0 pontos). Resultados: Foram selecionados quatro artigos, que abordaram a avaliação da força muscular respiratória, sua comparação entre os sexos e a determinação de equações preditivas. Conclusão: As equações estabelecidas por Lanza et al. e Verma et al. são possíveis alternativas para a determinação da força muscular respiratória em crianças e adolescentes; e as variáveis, idade e sexo foram as que melhor explicaram os valores de força muscular respiratória. (AU)

Objective: To review the prediction equations for respiratory muscle strength in children and adolescents and identify the independent variables with greater predictive power for respiratory muscle strength. Methods: This is a systematic review that was carried out using the databases: PEDro, MedLine / PubMed, Cochrane Library, LILACS / BVS Library, SciELO and Google Scholar. There were included articles with children and adolescents, published between 2009 and 2019, in Portuguese, English and Spanish, whose assessment method used manovacuometry and predictive equations were proposed. Studies that were not available in full, duplicated or with low methodological quality (PEDro scale <5.0 points) were excluded. Results: Four articles were selected, which addressed the evaluation of the respiratory muscle strength, its comparison between the sexes and the determination of predictive equations. Conclusion: The equations established by Lanza et al. and Verma et al. are possible alternatives for determining respiratory muscle strength in children and adolescents; the variables, age and sex were the ones that best explained the respiratory muscle strength values. (AU)

Objetivo: Revisar las ecuaciones de predicción para la fuerza muscular respiratoria en niños y adolescentes e identificar lãs variables independientes con mayor poder predictivo para La fuerza muscular respiratoria. Métodos: Esta es una revisión sistemática que se realizó en las bases de datos: PEDro, MedLine / PubMed, Cochrane Library, LILACS / BVS Library, SciELO y Google Scholar. Se incluyeron artículos con niños y adolescentes, publicados entre 2009 y 2019, en portugués, inglés y español, cuyo método de evaluación utilizó manovacuometría y se propusieron ecuaciones predictivas. Se excluyeron los estudios que no estaban disponibles en su totalidad, duplicados o con baja calidad metodológica (escala PEDro <5.0 puntos). Resultados: Se seleccionaron cuatro artículos, que abordaron La evaluación de La fuerza muscular respiratoria, su comparación entre géneros y la determinación de ecuaciones predictivas. Conclusión: Las ecuaciones establecidas por Lanza et al. y Verma et al. son posibles alternativas para determinar La fuerza muscular respiratória em niños y adolescentes, brasileños y otras nacionalidades, respectivamente; las variables, edad y sexo fueronlas que mejor explicaron los valores de fuerza muscular respiratoria. (AU)

Impacto do exercício físico no comportamento de idosas com alzheimer / Impact of physical exercise on behavior of elderly women bearing alzheimer's disease / Impacto del ejercicio físico en el comportamiento de mujeres mayores con alzheimer

Objetivo: Comparar o impacto do exercício físico no comportamento de idosas com Alzheimer em uma Instituição de longa permanecia para idosos. Método: Ensaio clínico não randomizado, com nove idosas com Doença de Alzheimer, residentes em uma instituição de longa permanência. Que foram submetidas diariamente, por quatro semanas, à aplicação de dois questionários, um para estabelecer o perfil individual de cada moradora, e outro para análise dos comportamentos característicos da doença. Resultados: Observa-se que nove dentre os medicamentos consumidos possuíam características para modulação comportamental (55,56% Quetiapina; 22,22% Depakote e/ou Exelon Patch; 11,11% de Donaren, Donepezila, Donila Duo, Escitalopran, Exodus e/ou Sertralina); após quatro semanas, 44,44% (n=4) das moradoras apresentaram diminuição das alterações comportamentais, para os períodos com exercício físico (p<0,05); as médias de alterações comportamentais da amostra total, foram de 0,76±0,38 e 1,60±0,70 para os períodos com e sem exercício físico, respectivamente (p<0,05); e comportamentos como "agressividade direcionada a equipe", "irritabilidade" e "outras alterações", apresentaram Δ de variação de 0,80; 2,04; e 1,21; respectivamente (p<0,05). Conclusão: A inclusão de exercícios físicos de maneira regular, em uma Instituição de longa permanecia para idosos, é capaz de reduzir alterações comportamentais à curto prazo em idosas com Doença de Alzheimer institucionalizadas. (AU)

Objective: Comparison of the impact of physical exercise on the behavior of elderly women with Alzheimer's in a long-stay institution for the elderly. Methods: Non-randomized clinical trial, with nine elderly women with Alzheimer's Disease, residing in a long-term institution. They were submitted daily, for four weeks, to the application of two questionnaires, one to establish the individual profile of each resident, and the other to analyze the characteristic characteristics of the disease. Results: It is observed that nine among the drugs consumed had characteristics for behavioral modulation (55.56% Quetiapine; 22.22% Depakote and/or Exelon Patch; 11.11% of Donaren, Donepezila, Donila Duo, Escitalopran, Exodus and / or Sertraline); after four weeks, 44.44% (n = 4) of residents reduced behavioral changes for periods with physical exercise (p < 0.05); as means of behavioral changes in the total sample, they were 0.76 ± 0.38 and 1.60 ± 0.70 for the periods with and without physical exercise, respectively (p < 0.05); and behavior such as "aggressiveness directed at the team", "irritability" and "other changes", similar to a variation of 0.80; 2.04; and 1.21; respectively (p<0.05). Conclusion: The inclusion of physical exercise on a regular basis, in a long-stay institution for the elderly, is capable of reducing short-term behavioral changes in institutionalized elderly women with Alzheimer's Disease. (AU)

Objetivo: Comparación del impacto del ejercicio físico en el comportamiento de mujeres mayores con Alzheimer en una institución de larga estancia para ancianos. Métodos: Ensayo clínico no aleatorizado, con nueve ancianas con enfermedad de Alzheimer, residentes en una institución de larga duración. Fueron sometidos diariamente, durante cuatro semanas, a la aplicación de dos cuestionarios, uno para establecer el perfil individual de cada residente y otro para analizar las características características de la enfermedad. Resultados: Se observa que nueve de los fármacos consumidos tenían características de modulación conductual (55,56% Quetiapina; 22,22% Depakote y / o Exelon Patch; 11,11% de Donaren, Donepezila, Donila Duo, Escitalopran, Exodus y / o Sertralina); después de cuatro semanas, el 44,44% (n = 4) de los residentes redujeron los cambios de comportamiento por períodos con ejercicio físico (p <0,05); como medias de los cambios de comportamiento en la muestra total fueron 0,76 ± 0,38 y 1,60 ± 0,70 para los períodos con y sin ejercicio físico, respectivamente (p <0,05); y comportamientos como "agresividad dirigida al equipo", "irritabilidad" y "otros cambios", similar a una variación de 0,80; 2,04; y 1,21; respectivamente (p <0,05). Conclusión: La inclusión de ejercicio físico de forma regular, en una institución de larga estancia para ancianos, es capaz de reducir los cambios conductuales a corto plazo en mujeres ancianas institucionalizadas con enfermedad de Alzheimer. (AU)

Effect of Resistance Training With Total and Partial Blood Flow Restriction on Biomarkers of Oxidative Stress and Apoptosis in Untrained Men.

Introduction: The characterization of immune and oxidative stress responses to acute and chronic exercise training is important because it may aid in the safety and dose-response prescription of resistance training (RT) in many populations. Purpose: The present study compared changes in acute oxidative stress and markers of apoptosis in immune cells before and after 8 weeks of low-load RT with total or partial blood flow restriction (BFR) versus high-load traditional RT. Methods: Twenty-seven untrained men were randomly divided into three groups: traditional RT [75% one-repetition maximum (1-RM)], RT with partial (20% 1-RM), and total BFR (20% 1-RM). Over an 8-week period, participants performed six sets of arm curls until failure with 90 seconds of recovery for 3 days/week. Blood samples were obtained before and after the first and last training sessions. Results: Data indicated that all training groups showed similar increases in muscular strength (p < 0.001), reduction in mitochondrial membrane potential (MMP) after exercise in neutrophils (p < 0.001), and increase in caspase-3 activity after exercise (p < 0.001). Traditional RT and total BFR showed increased plasma lipid peroxidation (p < 0.001) and protein carbonyls (p < 0.001) and lower levels of reduced glutathione (GSH) (p < 0.001) after exercise. No change was observed in oxidative stress biomarkers in response to partial BFR (p > 0.05). Conclusion: Data show that RT with partial BFR can increase muscular strength but still does not augment biomarkers of oxidative stress in untrained men. In addition, RT with total BFR promoted similar responses of oxidative stress and markers of immune cell apoptosis versus traditional RT.

Effect of high intensity interval training on body composition in women before and after menopause: a meta-analysis.

NEW FINDINGS: What is the topic of this review? A meta-analysis of the efficacy of high intensity interval training (HIIT) in reducing weight, total fat mass (FM) and (intra)-abdominal FM in normal-weight and overweight/obese women before and after menopause. What advances does it highlight? HIIT programmes in women significantly decrease body weight and total and abdominal FM. Their effects are more evident in pre- than in postmenopausal women. Cycling HIIT seems more effective than running, especially in postmenopausal women, and training interventions longer than 8 weeks comprising three sessions a week should be promoted. ABSTRACT: High-intensity interval training (HIIT) is a stimulating modality for reducing body weight and adipose tissue. The purpose of this meta-analysis was to assess the efficacy of HIIT in reducing weight, total fat mass (FM) and (intra)-abdominal FM in normal-weight and overweight/obese women before and after menopause. A structured electronic search was performed to find all publications relevant to our review. Stratified analyses were made of hormonal status (pre- vs. postmenopausal state), weight, HIIT modalities (cycling vs. running), programme duration (< or ≥8 weeks) and the methods used to measure body composition (dual-energy X-ray absorptiometry vs. computed tomography, Magnetic Resonance Imaging and others). A total of 38 studies involving 959 subjects were included. Our meta-analysis showed that overall HIIT programmes significantly decrease weight, total and abdominal FM in women. Both normal weight and overweight/obese women lost total FM after HIIT protocols whereas HIIT was only effective in decreasing abdominal FM in women with excess adiposity. When pre- and postmenopausal women were considered separately, the effect of HIIT on weight, total and abdominal FM were only significant before menopause. Cycling HIIT seemed more effective than running, especially in postmenopausal women, and training interventions longer than 8 weeks comprising three sessions were more efficient. HIIT is a successful strategy to lose weight and FM in normal weight and overweight/obese women. However, further studies are still needed to draw meaningful conclusions about the real effectiveness of HIIT protocols in postmenopausal women.

The Goal Scale: A New Instrument to Measure the Perceived Exertion in Soccer (Indoor, Field, and Beach) Players.

The rating of perceived exertion (RPE) can be used to monitor the exercise intensity during laboratory and specific tests, training sessions, and to estimate the internal training load of the athletes. The aim of the present study was to develop and validate a specific pictorial perceived exertion scale for soccer players (indoor, field, and beach soccer) called GOAL Scale. The pictorial GOAL Scale (six drawings; 1 "low exertion" to 6 "exhaustion") was validated for twenty under-17 soccer players (16.4 ± 0.68 years; 175.4 ± 9 cm; 66.4 ± 7.7 kg; % fat mass 12.4 ± 3.3). In the validation phase, the athletes were evaluated in a progressive protocol involving stimuluses of 3 min with 1 min for the rest into the stages until the voluntary exhaustion in Maximal Cardiopulmonary Effort Test (MCET), and in the Yo Yo Intermittent Recovery Test - Level 1 (Yo-Yo). The RPE identified by the GOL Scale, by the Borg Scale 6 - 20 and by the Cavasini Scale, as well as the heart rate (HR), perceptual of the heart rate (%HRmax) and the blood lactate concentration ([La]) were immediately evaluated after each stage of both tests. Spearman's correlation coefficient (p < 0.05) was used. Construct scale validity was examined by regressing GOAL Scale against Borg Scale 6 - 20 and Cavasini Scale and concurrent scale validity was investigated by regressing GOAL Scale against HR, beats/min and blood lactate concentration (mmol/L) during two progressive tests. There was a significant correlation values of the GOAL Scale with Borg Scale (r = 0.93; r = 0.88), Cavasini Scale (r = 0.91; r = 0.90), %HRmax (r = 0.91; r = 0,86), HR (r = 0.87; r = 0.83) and lactate (r = 0.68; r = 0.83) during tests (Maximal Incremental Cardiopulmonary Test and Yo-Yo test, respectively). The results evidenced concurrent and construct validity of the GOAL Scale across a wide range of exercise intensity. The absence of verbal anchors makes the use of this instrument to soccer, futsal and beach soccer athletes of different languages and different literacy levels possible.

Six hit treadmill sessions improve lipid oxidation and ventilatory threshold intensities / Seis sessões de hit em esteira aumentam a oxidação de lipídios e limiares ventilatórios / Seis sesiones de hit en cinta de correr aumentan la oxidación de lípidos y umbrales ventilatorios

ABSTRACT Introduction: High-intensity interval training (HIT) has been used as an alternative to cardiorespiratory training performed continuously at submaximal intensity and over long periods. Objectives: Propose a treadmill HIT protocol and verify the influence of six HIT sessions with this protocol on ventilatory anaerobic thresholds (VATs) and substrate oxidation pattern during submaximal continuous exercise (SCE). Methods: Fifteen sporadically active subjects underwent maximal progressive testing before and after six HIT treadmill running sessions to determine peak oxygen uptake (VO2peak), peak velocity (Vpeak), and VATs followed by SCE to determine lipid (LIPox) and carbohydrate (CHOox) oxidation rates. The HIT sessions consisted of eight sets of 60s at 100%Vpeak, interspersed with 75s of passive recovery between sets and a 48h interval between sessions. Results: Our results showed increases in VAT intensities of 4.4% for VAT1 and 8.8% for VAT2, a decrease of 12.8% in CHOox and an increase of 23.7% for LIPox; accordingly, the relative energy derived from LIPox was 20.3% higher after the training period. Vpeak was ~15 km/h, producing intensities corresponding to ~84%VO2peak and ~91%FCpeak over the training period. Conclusion: The proposed protocol produced adaptations and intensities which are similar to those described in the literature, but unlike others, it can be applied in sporadically active individuals. Level of Evidence II; Comparative prospective study.

RESUMO Introdução: O treinamento cardiorrespiratório intervalado de alta intensidade (high-intensity interval training, HIT) tem sido utilizado como alternativa ao treinamento cardiorrespiratório contínuo de intensidade submáxima e duração prolongada. Objetivo: Propor um protocolo de HIT utilizando corrida em esteira e verificar a influência de seis sessões de HIT com esse protocolo sobre os limiares anaeróbios ventilatórios (LAVs) e o padrão de oxidação de substratos durante o exercício contínuo de intensidade submáxima (ECIS). Métodos: Quinze indivíduos irregularmente ativos foram submetidos, antes e após seis sessões de HIT com corrida em esteira, a teste progressivo máximo para determinação do pico de consumo de oxigênio (VO2pico), velocidade de pico (Vpico) e LAVs seguidos de ECIS para determinação das taxas de oxidação de lipídios (LIPox) e carboidratos (CHOox). As sessões de HIT eram compostas por oito séries de 60 segundos a 100%Vpico com 75 segundos de recuperação passiva entre as séries e com 48 horas de intervalo entre as sessões. Resultados: Observaram-se aumentos das intensidades de ocorrência dos LAVs (4,4% para LAV1 e 8,8% para LAV2), redução de 12,8% de CHOox e aumento de 23,7% de LIPox; como consequência, a energia relativa derivada de LIPox apresentou-se 20,3% maior após o período de treinamento. A Vpico foi de ~15 km/h, promovendo intensidades correspondentes a ~84%VO2pico e ~91%FCpico ao longo do período de treinamento. Conclusão: O protocolo proposto promoveu adaptações e intensidades similares às descritas na literatura; porém, ao contrário de outros, é passível de aplicação em indivíduos irregularmente ativos. Nível de Evidência II; Estudo prospectivo comparativo.

RESUMEN Introducción: El entrenamiento cardiorrespiratorio intermitente de alta intensidad (high-intensity interval training, HIT) ha sido utilizado como alternativa al entrenamiento cardiorrespiratorio continuo de intensidad submáxima y duración prolongada. Objetivo: Proponer un protocolo de HIT utilizando carrera en cinta y verificar la influencia de seis sesiones de HIT con ese protocolo sobre los umbrales anaeróbicos ventilatorios (UAVs) y el patrón de oxidación de substratos durante el ejercicio continuo de intensidad submáxima (ECIS). Métodos: Quince individuos irregularmente activos fueron sometidos, antes y después de seis sesiones de HIT con carrera en cinta, a test progresivo máximo para determinación del pico de consumo de oxígeno (VO2pico), velocidad de pico (Vpico) y UAVs seguidos de ECIS para determinación de las tasas de oxidación de lípidos (LIPox) y carbohidratos (CHOox). Las sesiones de HIT eran compuestas por ocho series de 60 segundos a 100%Vpico con 75 segundos de recuperación pasiva entre las series y con 48 horas de intervalo entre las sesiones. Resultados: Se observaron aumentos de las intensidades de ocurrencia de los UAVs (4,4% para UAV1 y 8,8% para UAV2), reducción de 12,8% de CHOox y aumento de 23,7% de LIPox; como consecuencia, la energía relativa derivada de LIPox se presentó 20,3% mayor después del período de entrenamiento. La Vpico fue de ~15 km/h, promoviendo intensidades correspondientes a ~84%VO2pico e ~91%FCpico a lo largo del período de entrenamiento. Conclusión: El protocolo propuesto promovió adaptaciones e intensidades similares a las descritas en la literatura; sin embargo, al contrario de otros, es pasible de aplicación en individuos irregularmente activos. Nivel de Evidencia II; Estudio prospectivo comparativo.

A note on motor skill acquisition in mild and moderate Down syndrome individuals.

This study investigated the acquisition of a serial motor skill in individuals with Down syndrome with two levels of handicap, mild group (mean age = 14.5 years, SD = 2.3, 7 individuals) and moderate group (mean age = 15.2 years, SD = 3.2, 7 individuals). The task involved single-arm sequential movements to five. The measures to access performance were overall sequence error, reaction time, and total movement time. To evaluate action program, formation variability of sequencing and relative timing variability were considered. Although there was no clear practice effect, the results showed that the level of handicap led to different strategies to plan and control the actions. The moderate group presented a less stable action program expressed in the variability in sequencing and timing. Their longer reaction times also suggest a heavy demand on central processing in accord with the one-target advantage hypothesis and also due to memory deficits to select and plan movements.

A note on motor skill acquisition in mild and moderate Down syndrome individuals

Abstract This study investigated the acquisition of a serial motor skill in individuals with Down syndrome with two levels of handicap, mild group (mean age = 14.5 years, SD = 2.3, 7 individuals) and moderate group (mean age = 15.2 years, SD = 3.2, 7 individuals). The task involved single-arm sequential movements to five. The measures to access performance were overall sequence error, reaction time, and total movement time. To evaluate action program, formation variability of sequencing and relative timing variability were considered. Although there was no clear practice effect, the results showed that the level of handicap led to different strategies to plan and control the actions. The moderate group presented a less stable action program expressed in the variability in sequencing and timing. Their longer reaction times also suggest a heavy demand on central processing in accord with the one-target advantage hypothesis and also due to memory deficits to select and plan movements.

DESEMPENHO DE INDIVÍDUOS COM DERMOPIGMENTAÇÃO SUBMETIDOS À PRÁTICA DE EXERCÍCIO FÍSICO / PERFORMANCE OF DERMAL PIGMENTED INDIVIDUALS SUBMITTED TO PHYSICAL EXERCISE / DESEMPEÑO DE INDIVIDUOS CON DERMOPIGMENTACIÓN SOMETIDOS A PRÁCTICA DE EJERCICIOS FÍSICOS

RESUMO Introdução: A duração e a intensidade dos exercícios provocam diferentes alterações no sistema imunológico, dentre elas a diminuição das respostas imunes, acarretando queda no desempenho físico. Sabe-se também que a dermopigmentação pode colaborar com tais alterações no comportamento deste sistema. Objetivo: Avaliar os efeitos da dermopigmentação sobre o desempenho no exercício físico. Método: Neste ensaio clínico participaram 12 sujeitos, dentre eles seis com dermopigmentação, idade (anos), peso (Kg), estatura (cm) e gordura corporal (%) de 16,5 ± 1,16; 68,10 ± 6,83; 176,29 ± 7,71; 11,49 ± 0,58 respectivamente, divididos em dois grupos, sendo submetidos a teste de esforço máximo com intensidade progressiva em esteira ergométrica para determinação do consumo máximo de oxigênio (VO2máx), limiares anaeróbios (LAns) e economia de corrida (EC 14km/h %), sendo realizadas coletas de lactato pré e 5 minutos pós-teste. Os dados foram tratados por "teste t" para variáveis independentes, tendo como nível de significância adotado α < 0,05. Resultados: Foram observadas diferenças significativas entre os grupos em relação à concentração sanguínea de lactato (CSL) pré-teste (4,6 ± 0,11 e 3,23 ± 0,88 para dermopigmentados e não dermopigmentados, respectivamente; p < 0,05) e 5 minutos pós-teste (5,65 ± 0,49 e 13,13 ± 2,20 para dermopigmentados e não dermopigmentados, respectivamente; p < 0,05). O tempo de teste também foi significativamente superior para o grupo não dermopigmentado em comparação ao grupo com dermopigmentação (8 min 47 seg ± 0,08 e 7 min 39 seg ± 0,03 respectivamente; p < 0,05), bem como análise do WURSS-21 (3,33 ± 3,14 e 2,00 ± 1,09, respectivamente; p > 0,05). Em relação às demais variáveis dependentes (VO2máx, segundo limiar anaeróbio e economia de corrida) não foram encontradas diferenças estatisticamente significativas. Conclusão: A dermopigmentação produziu rendimento inferior no teste de esforço máximo, influenciando o desempenho no exercício físico.

ABSTRACT Introduction: Duration and intensity of exercises cause different alterations in the immunity system, among them, reduction of immunity responses, causing decrease in physical performance. It is also known that dermal pigmentation can influence such alterations in the system's behavior. Objective: To evaluate the effects of dermal pigmentation on performance of physical exercise. Method: In this clinical essay, 12 subjects participated, among them, 6 with dermal pigmentation, being age (years), weight (kg), height (cm) and body fat (%) measured as 16.5 ± 1.16; 68.10 ± 6.83; 176.29 ± 7.71; 11.49 ± 0.58, respectively, divided in two groups. They were submitted to a maximum effort test with gradual intensity in treadmill to determine maximum oxygen consumption (VO2max), anaerobic thresholds (AnT) and running economy (RE 14km/h %), lactate being collected before and 5 minutes after test. Data has been analyzed by "t test" for independent variables, having a level of significance of α < 0.05. Results: Significant differences were observed between groups in relation to pre-test blood lactate concentration (BLC) (4.6 ± 0.11 and 3.23 ± 0.88 for the dermal pigmented and non-dermal pigmented groups, respectively; p <0.05) and 5 minutes post-test (5.65 ± 0.49 and 13.13 ± 2.20 for the dermal pigmented and non-dermal pigmented groups, respectively; p <0.05). The testing time was also significantly higher for the non-dermal pigmented group, compared to the dermal pigmented group (8 min 47 sec ± 0.08 and 7 min 39 sec ± 0.03 respectively; p < 0.05) and also analysis of WURSS-21 (3.33 ± 3.14 and 2.00 ± 1.09, respectively; p> 0.05). In relation to the other dependent variables (VO2max, second anaerobic threshold and running economy) no statistically significant differences were found. Conclusion: Dermal pigmentation produced lower performance in the maximum effort test, with an influence on performance of physical exercise.

RESUMEN Introducción: La duración e intensidad del ejercicio provocan diferentes cambios en el sistema inmunológico, entre ellos, la reducción de las respuestas inmunes, lo que resulta en disminución en el rendimiento físico. También se sabe que la dermopigmentación puede colaborar con tales cambios en el comportamiento de este sistema. Objetivo: Evaluar los efectos de dermopigmentación en el rendimiento del ejercicio físico. Método: En este ensayo clínico participaron 12 sujetos, entre ellos seis con dermopigmentación, con edad (años), peso (kg), altura (cm) y grasa corporal (%) de 16,5 ± 1,16; 68,10 ± 6,83; 176,29 ± 7,71; 11,49 ± 0,58, respectivamente, divididos en dos grupos. Estos se sometieron a la prueba de esfuerzo máximo con intensidad progresiva en una cinta ergométrica para determinar el consumo máximo de oxígeno (VO2máx), umbrales anaeróbicos (UA) y la economía de carrera (EC 14km/h %), con colecciones de lactato pre y 5 minutos después de la prueba. Los datos fueron analizados por "prueba t" para las variables independientes, teniendo un nivel de significación adoptado de α < 0,05. Resultados: Se observaron diferencias significativas entre los grupos con respecto a la concentración de lactato en sangre (CLS) pre-test (4,6 ± 0,11 y 3,23 ± 0,88 para dermopigmentados y no dermopigmentados, respectivamente; p < 0,05) y 5 minutos después de la prueba (5,65 ± 0,49 y 13,13 ± 2,20 para dermopigmentados no dermopigmentados, respectivamente; p < 0,05). El tiempo de prueba fue también significativamente mayor para el grupo no dermopigmentado en comparación con el grupo con dermopigmentación (8 min 47 seg ± 0,08 y 7 min 39 seg ± 0,03, respectivamente; p <0,05) y WURSS-21 análisis (3,33 ± 3,14 y 2,00 ± 1,09 respectivamente; p> 0,05). En cuanto las demás variables dependientes (VO2máx, segundo umbral anaeróbico y economía de carrera) no se encontraron diferencias estadísticamente significativas. Conclusión: La dermopigmentación produjo bajo rendimiento en la prueba de esfuerzo máximo, que influye en el rendimiento del ejercicio físico.

Effect of aspartate and asparagine supplementation on fatigue determinants in intense exercise.

PURPOSE: This study evaluated the effect of aspartate (ASP) and asparagine (ASG) supplementation on fatigue determinants in Wistar rats exercised to exhaustion by swimming. METHODS: The animals were tested for anaerobic threshold (AT) determination and then supplemented with 350 mM ASP + 400 mM ASG x day(-1) (AA group, n = 16) or 2 ml x day(-1) of distillated water (PLC group, n = 16) for 7 days. On the 7th day of supplementation, the animals were divided into 4 new groups and killed at rest (RAA, n = 8; RPLC, n = 8), or immediately after the swimming exercise to exhaustion (EAA, n = 8; EPLC, n = 8). R: No significant differences were observed between amino acids and placebo rest groups for muscle and liver glycogen, blood glucose, lactate, alanine, and glutamine concentrations. However, in the exhaustion groups, the EAA group showed higher exercise time (68.37 +/- 25.42 x 41.12 +/- 13.82 min, p <.05) and lower blood lactate concentration (8.57 +/- 1.92 x 11.28 +/- 2.61 mmol x L(-1), p <.05) than the EPLC group. Moreover, the ASP+ASG supplementation decreased the rate of glycogen degradation of gastrocnemius (1.00 +/- 0.51 x 3.43 +/- 0.99 microg x 100 mg of tissue sample(-1) x min(-1), extensor digitorius longus (5.70 +/- 2.35 x 8.11 +/- 3.97 microg. 100 mg of tissue sample(-1) x min(-1) and liver (0.51 +/- 0.34 x 3.37 +/- 2.31 microg x 100 mg of tissue sample(-1) x min(-1) for EAA. CONCLUSION: These results suggest that ASP+ASG supplementation may increase the contribution of oxidative metabolism in energy production and delay fatigue during exercise performed above the AT.

Dietas hiperlipídicas e freqüência alimentar: efeitos sobre as reservas lipídicas em ratos / Fat enriched diets and meal feeding: effects on body fat in rats

O objetivo deste estudo foi avaliar a composição corporal, consumo alimentar e tolerância à glicose de ratas submetidas a diferentes freqüências de ingestão alimentar associadas a dietas hiperlipídicas (HL). Ratas Wistar foram acompanhadas por 8 semanas divididas em: C2h (controle intermitente, com ingestao de ração comercial 1x/dia durante 2h/dia); HL2h (HL intermitente, com consumo de HL 1x/dia por 2h/dia); C24h (controle fracionado, com acesso 24h/d à ração comercial) e HL24h (HL fracionada, com acesso 24h/d à ração HL). Os grupos com dieta HL ingeriram menos alimento que os controles, porém com mesma ingestão energética. Animais com apenas 2h de acesso diário ao alimento ingeriram apenas cerca de 62 por cento das calorias consumidas pelos animais com ingestão ®ad libitum...

Estratégias de reposiçäo hídrica: revisäo e recomendaçöes aplicadas / Water replacement strategies: review and practical applications

Grande atençäo tem-se dado às estratégias de reidrataçäo durante e após a atividade física, como forma de manter os líquidos corporais. Quando discutimos a necessidade de repor as perdas hídricas associadas à atividade física, buscamos, em última análise, formas de prolongar ou manter pelo maior tempo possível o rendimento do indivíduo. Alteraçöes das funçöes fisiológicas consequentes das perdas hídricas comprometem o desempenho, tornando-se assim fatores determinantes de fadiga. Este artigo de revisäo discute a necessidade de repor as perdas hídricas associadas à atividade física, apresentando algumas estratégias presentes na literatura. Alguns artigos consideram a reposiçäo hídrica, em conjunto com a oferta de nutrientes e eletrólitos, como um importante recurso ergogênico, já que a depleçäo de substratos energéticos (glicogênio muscular e hepático), o acúmulo de metabólitos (lactato e íons H) e o prejuízo dos processos de termorregulaçäo estäo intimamente ligados à diminuiçäo do desempenho. Assim, além da oferta de água, as estratégias discutidas nesta revisäo procuram também avaliar a disponibilidade de carboidratos e eletrólitos, quer como agentes facilitadores da própria reposiçäo hídrica ou como fonte exógena de substrato

Possível efeito da suplementaçäo de aminoácidos de cadeia ramificada, aspartato e asparagina sobre o limiar anaeróbio / Possible effect of the supplementation of branched chain aminoacids, aspartate and asparagine on anaerobic threshold

Recentemente o conceito "Limiar Anaeróbio" tem sido muito criticado. As prinipais criticas repousam sobre os mecanismos considerados para o aumento da concentraçäo de lactato sangüíneo, hipóxia muscular principalmente, e sobre a suposta relaçäo de causa-e-efeito entre os limiares metabólico e ventilatório. Apesar de criticado, o conceito Limiar Anaeróbio encontrou muitas aplicaçöes, e por esta razäo, vários estudos foram realizados para facilitar a sua determinaçäo näo invasivamente, a partir de parâmetros ventilatórios e da deflexäo da curva de freqüência cardíaca. Recentemente o uso de aminoácidos tem se difundido largamente entre os praticantes de atividades motoras, tornando-se objeto de estudo para vßrios pesquisadores. Foi proposto que a suplementaçäo de aminoácidos de cadeia ramificada, aspartato e asparagina promove aumento da resistência ao esforço físico prolongado, em decorrência do aumento do conteúdo de glicogênio muscular e síntese de oxaloacetato para manutençäo da atividade do ciclo de Krebs e do próprio metabolismo oxidativo. Com isto o transporte de glicose para o interior da célula muscular diminui, retardando a depleçäo de glicogênio muscular e a acidose metabólica, causas evidentes de fadiga. Em conseqüência, a oxidaçäo de AGLs durante o exercício contínuo moderado aumenta, retardando o acúmulo de lactato sangüíneo e muscular. Isto retardaria o estímulo metabólico para o processo de tamponamento pelo HCO3 e a conseqüente compensaçäo ventilatória para CO2, podendo dissociar os limiares metabólico e ventilatório. A dissociaçäo dos limiares reforçaria as críticas sobre o conceito Limiar Anaeróbio e poderia, inclusive, prejudicar a sua identificaçäo através de outros métodos, como por exemplo, a deflexäo da curva de freqüência cardíaca.