785 resultados para Fatigue. Aged. Physical exertion


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Background. Ambulatory blood pressure (ABP) measurement is a means of monitoring cardiac function in a noninvasive way, but little is known about ABP in heart failure (HF) patients. Blood pressure (BP) declines during sleep as protection from consistent BP load, a phenomenon termed "dipping." The aims of this study were (1) to compare BP dipping and physical activity between two groups of HF patients with different functional statuses and (2) to determine whether the strength of the association between ambulatory BP and PA is different between these two different functional statuses of HF. ^ Methods. This observational study used repeated measures of ABP and PA over a 24-hour period to investigate the profiles of BP and PA in community-based individuals with HF. ABP was measured every 30 minutes by using a SpaceLabs 90207, and a Basic Motionlogger actigraph was used to measure PA minute by minute. Fifty-six participants completed both BP and physical activity for a 24-hour monitoring period. Functional status was based on New York Heart Association (NYHA) ratings. There were 27 patients with no limitation of PA (NYHA class I HF) and 29 with some limitation of PA but no discomfort at rest (NYHA class II or III HF). The sample consisted of 26 men and 30 women, aged 45 to 91 years (66.96 ± 12.35). ^ Results. Patients with NYHA class I HF had significantly greater dipping percent than those with NYHA class II/III HF after controlling their left ventricular ejection fraction (LVEF). In a mixed model analysis (PROC MIXED, SAS Institute, v 9.1), PA was significantly related to ambulatory systolic and diastolic BP and mean arterial pressure. The strength of the association between PA and ABP readings was not significantly different for the two groups of patients. ^ Conclusions. These preliminary findings demonstrate differences between NYHA class I and class II/III of HF in BP dipping status and ABP but not PA. Longitudinal research is recommended to improve understanding of the influence of disease progression on changes in 24-hour physical activity and BP profiles of this patient population. ^ Key Words. Ambulatory Blood Pressure; Blood Pressure Dipping; Heart Failure; Physical Activity. ^

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Background. With the rapid rise in childhood obesity, physical activity participation among young children has become the subject of much recent attention. Physical education classes have been specifically targeted as a method of providing opportunities for all children to be active. Unfortunately, student participation in moderate-to-vigorous physical activity during these classes still falls far below the current recommendations. While some research to date has reported the levels of activity among elementary-aged children, research is limited on the relationship between these activity levels and the environmental characteristics that exist within the PE classroom. ^ Purpose. The purpose of this study is to examine the association between specific classroom characteristics and contextual characteristics (lesson context, class size, class location, teacher gender, and teacher encouragement for PA) with elementary aged children's moderate-to-vigorous activity during PE class. ^ Methods. A secondary analysis of 211 3rd, 4th and 5th grade physical education classes amongst 39 elementary schools in Harris County, TX and 35 elementary schools in Travis County, TX was conducted using cross-sectional data from the evaluation of a school-based health program. Lesson context and student activity levels were measured using a direct observation measurement tool. Additionally, these variables were further analyzed against a number of classroom characteristics to determine any significant associations. ^ Results. Overall, elementary PE classes are still participating in low levels of moderate-to-vigorous physical activity averaging only 38% of class time. Additionally, close to 25% of class time is spent in classroom management. Male directed classes spent significantly more time in game activities and female directed classes spent more time in fitness, knowledge, and skill activities. Classes that took place outdoors were more active and spent more time in games than those that took place indoors. Significant correlations were demonstrated between class size and time spent in management context. Time spent in management context was also correlated with time spent sitting and standing. Additionally, positive correlations were demonstrated between time very active and teachers that praised students and encouraged physical activity among their classes.^

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Childhood obesity is a significant public health problem. Over 15 percent of children in the United States are obese, and about 25 percent of children in Texas are overweight (CDC NHANES). Furthermore, about 30 percent of elementary school aged children in Harris County, Texas are overweight or obese (Children at Risk Institute 2010). In addition to actions such as increasing physical activity, decreasing television watching and video game time, decreasing snacking on low nutrient calorie dense foods and sugar sweetened beverages, children need to consume more fruits and vegetables. According to the National Health and Nutrition Examination Survey (NHANES) from 2002, about 26 percent of U.S. children are meeting the recommendations for daily fruit intake and about 16 percent are meeting the recommendations for daily vegetable intake (CDC NHANES). In 2004, the average total intake of vegetables was 0.9 cups per day and 1.1 cups of fruit per day by children ages four to nine years old in the U.S. (CDC NHANES). Not only do children need effective nutrition education to learn about fruits and vegetables, they also need access and repeated exposure to fruits and vegetables (Anderson 2009, Briefel 2009). Nutrition education interventions that provide a structured, hands-on curriculum such as school gardens have produced significant changes in child fruit and vegetable intake (Blair 2009, McAleese 2007). To prevent childhood obesity from continuing into adolescence and adulthood, effective nutrition education interventions need to be implemented immediately and for the long-term. However, research has shown short-term nutrition education interventions such as summer camps to be effective for significant changes in child fruit and vegetable intake, preferences, and knowledge (Heim 2009). ^ A four week summer camp based on cooking and gardening was implemented at 6 Multi-Service centers in a large, urban city. The participants included children ranging in age from 7 to 14 years old (n=64). The purpose of the camp was to introduce children to their food from the seed to the plate through the utilization of gardening and culinary exercises. The summer camp activities were aimed at increasing the children's exposure, willingness to try, preferences, knowledge, and intake of fruits and vegetables. A survey was given on the first day of camp and again on the last day of camp that measured the pre- and post differences in knowledge, intake, willingness to try, and preferences of fruits and vegetables. The present study examined the short-term effectiveness of a cooking and garden-based nutrition education program on the knowledge, willingness, preferences, and intake among children aged 8 to 13 years old (n=40). The final sample of participants (n=40) was controlled for those who completed pre- and post-test surveys and who were in or above the third grade level. Results showed a statistically significant increase in the reported intake of vegetables and preferences for vegetables, specifically green beans, and fruits. There was also a significant increase in preferences for fruits among boys and participants ages 11 to 13 years. The results showed a change in the expected direction of willingness to try, preferences for vegetables, and intake of fruit, however these were not statistically significant. Interestingly, the results also showed a decrease in the intake of low nutrient calorie dense foods such as sweets and candy.^

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Documented risks of physical activity include reduced bone mineral density at high activity volume, and sudden cardiac death among adults and adolescents. Further illumination of these risks is needed to inform future public health guidelines. The present research seeks to 1) quantify the association between physical activity and bone mineral density (BMD) across a broad range of activity volume, 2) assess the utility of an existing pre-screening questionnaire among US adults, and 3) determine if pre-screening risk stratification by questionnaire predicts referral to physician among Texas adolescents. ^ Among 9,468 adults 20 years of age or older in the National Health and Nutrition Examination Survey (NHANES) 2007-2010, linear regression analyses revealed generally higher BMD at the lumbar spine and proximal femur with greater reported activity volume. Only lumbar BMD in women was unassociated with activity volume. Among men, BMD was similar at activity beyond four times the minimum volume recommended in the Physical Activity Guidelines. These results suggest that the range of activity reported by US adults is not associated with low BMD at either site. ^ The American Heart Association / American College of Sports Medicine Preparticipation Questionnaire (AAPQ) was applied to 6,661 adults 40 years of age or older from NHANES 2001-2004 by using NHANES responses to complete AAPQ items. Following AAPQ referral criteria, 95.5% of women and 93.5% of men would be referred to a physician before exercise initiation, suggesting little utility for the AAPQ among adults aged 40 years or older. Unnecessary referral before exercise initiation may present a barrier to exercise adoption and may strain an already stressed healthcare infrastructure. ^ Among 3181 athletes in the Texas Adolescent Athlete Heart Screening Registry, 55.2% of boys and 62.2% of girls were classified as high-risk based on questionnaire answers. Using sex-stratified contingency table analyses, risk categories were not significantly associated with referral to physician based on electrocardiogram or echocardiogram, nor were they associated with confirmed diagnoses on follow-up. Additional research is needed to identify which symptoms are most closely related to sudden cardiac death, and determine the best methods for rapid and reliable assessment. ^ In conclusion, this research suggests that the volume of activity reported by US adults is not associated with low BMD at two clinically relevant sites, casts doubts on the utility of two existing cardiac screening tools, and raises concern about barriers to activity erected through ineffective screening. These findings augment existing research in this area that may inform revisions to the Physical Activity Guidelines regarding risk mitigation.^

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Damage models based on the Continuum Damage Mechanics (CDM) include explicitly the coupling between damage and mechanical behavior and, therefore, are consistent with the definition of damage as a phenomenon with mechanical consequences. However, this kind of models is characterized by their complexity. Using the concept of lumped models, possible simplifications of the coupled models have been proposed in the literature to adapt them to the study of beams and frames. On the other hand, in most of these coupled models damage is associated only with the damage energy release rate which is shown to be the elastic strain energy. According to this, damage is a function of the maximum amplitude of cyclic deformation but does not depend on the number of cycles. Therefore, low cycle effects are not taking into account. From the simplified model proposed by Flórez-López, it is the purpose of this paper to present a formulation that allows to take into account the degradation produced not only by the peak values but also by the cumulative effects such as the low cycle fatigue. For it, the classical damage dissipative potential based on the concept of damage energy release rate is modified using a fatigue function in order to include cumulative effects. The fatigue function is determined through parameters such as the cumulative rotation and the total rotation and the number of cycles to failure. Those parameters can be measured or identified physically through the haracteristics of the RC. So the main advantage of the proposed model is the possibility of simulating the low cycle fatigue behavior without introducing parameters with no suitable physical meaning. The good performance of the proposed model is shown through a comparison between numerical and test results under cycling loading.

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Este trabajo aborda la metodología seguida para llevar a cabo el proyecto de investigación PRONAF (Clinical Trials Gov.: number NCT01116856.) Background: At present, scientific consensus exists on the multifactorial etiopatogenia of obesity. Both professionals and researchers agree that treatment must also have a multifactorial approach, including diet, physical activity, pharmacology and/or surgical treatment. These two last ones should be reserved for those cases of morbid obesities or in case of failure of the previous ones. The aim of the PRONAF study is to determine what type of exercise combined with caloric restriction is the most appropriate to be included in overweigth and obesity intervention programs, and the aim of this paper is to describe the design and the evaluation methods used to carry out the PRONAF study. Methods/design: One-hundred nineteen overweight (46 males) and 120 obese (61 males) subjects aged 18–50 years were randomly assigned to a strength training group, an endurance training group, a combined strength + endurance training group or a diet and physical activity recommendations group. The intervention period was 22 weeks (in all cases 3 times/wk of training for 22 weeks and 2 weeks for pre and post evaluation). All subjects followed a hypocaloric diet (25-30% less energy intake than the daily energy expenditure estimated by accelerometry). 29–34% of the total energy intake came from fat, 14–20% from protein, and 50–55% from carbohydrates. The mayor outcome variables assesed were, biochemical and inflamatory markers, body composition, energy balance, physical fitness, nutritional habits, genetic profile and quality of life. 180 (75.3%) subjects finished the study, with a dropout rate of 24.7%. Dropout reasons included: personal reasons 17 (28.8%), low adherence to exercise 3 (5.1%), low adherence to diet 6 (10.2%), job change 6 (10.2%), and lost interest 27 (45.8%). Discussion: Feasibility of the study has been proven, with a low dropout rate which corresponds to the estimated sample size. Transfer of knowledge is foreseen as a spin-off, in order that overweight and obese subjects can benefit from the results. The aim is to transfer it to sports centres. Effectiveness on individual health-related parameter in order to determine the most effective training programme will be analysed in forthcoming publications.

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Purpose: It determines if participating in sports and/or physical activity influences perceived health among the elderly. Basic procedures: Data were drawn from a population subsample of subjects aged 65 - 79 years old that took part in a survey conducted in 2008 by the IESA-CSIC. A regression model was performed with perceived health status with the dependent variable and sociodemographic characteristics and physical activity as independent variables. Results: Physical activity is closely associated to per-ceived health, although sport has little influence on this relationship. Conclusions: Doing exercise or feeling that one is physically active makes the elderly feel better about their health status. However, this age group practises few sports and sport is not found to have an important or constant influence on self-perceived health status among the elderly.

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Objective: To examine the association of breakfast consumption with objectively measured and self-reported physical activity, sedentary time and physical fitness. Design: The HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Cross-Sectional Study. Breakfast consumption was assessed by two non-consecutive 24 h recalls and by a ‘Food Choices and Preferences’ questionnaire. Physical activity, sedentary time and physical fitness components (cardiorespiratory fitness, muscular fitness and speed/agility) were measured and self-reported. Socio-economic status was assessed by questionnaire. Setting: Ten European cities. Subjects: Adolescents (n 2148; aged 12?5–17?5 years). Results: Breakfast consumption was not associated with measured or self-reported physical activity. However, 24 h recall breakfast consumption was related to measured sedentary time in males and females; although results were not confirmed when using other methods to assess breakfast patterns or sedentary time. Breakfast consumption was not related to muscular fitness and speed/agility in males and females. However, male breakfast consumers had higher cardiorespiratory fitness compared with occasional breakfast consumers and breakfast skippers, while no differences were observed in females. Overall, results were consistent using different methods to assess breakfast consumption or cardiorespiratory fitness (all P#0?005). In addition, both male and female breakfast skippers (assessed by 24 h recall) were less likely to have high measured cardiorespiratory fitness compared with breakfast consumers (OR50?33; 95% CI 0?18, 0?59 and OR50?56; 95 %CI 0?32, 0?98,respectively). Results persisted across methods. Conclusions: Skipping breakfast does not seem to be related to physical activity,sedentary time or muscular fitness and speed/agility as physical fitness components in European adolescents; yet it is associated with both measured and self-reported cardiorespiratory fitness, which extends previous findings.

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More children with different versions of speech disorders appear in Russia last decades. This situation reflects general tendency of national health deterioration. Our practical experience shows that close grownups can?t communicate to children with limited health capacity. As a result there arise social disabilities in child development. Speech communication is one of the forms of global communicative interaction process between close grownups and young child in the course of which there is a redistribution of knowledge and ignorance (Nikas Luman,2005). Within a framework of sociocultiral theory of mental growth we consider the appearance of speech communication under any cases of physical illness is possible only under conditions of correctly- organized communication between grownups and young children. (L.S. Vigotski ,2000). The special value in this aspect acquires the study of communication between grownups and young children. For five years we have been conducting the surveys on the problem of communicative contacts between parents and non-verbal children. Analysis of received data gave us the opportunity to systematize peculiar communicative interaction of adults and children who have some lapses in acquiring speech form communication. We have revealed four versions of situational- business communication between close grownups and young children with disabilities in acquiring speech. We have assumed that four versions of situational- business communication negatively affect speech form communication formation.

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INTRODUCCIÓN Actualmente las supervivientes de cáncer de mama viven durante más tiempo. Sin embargo, los tratamientos utilizados presentan importantes efectos secundarios que afectan y marcan su calidad de vida. Numerosos estudios han mostrado que el ejercicio es una herramienta apta, segura y efectiva reduciendo algunos de estos efectos secundarios y, en suma, mejorando la calidad de vida de estas pacientes, aspecto que presenta al ejercicio físico como una intervención integral para ellas. Por el contrario, se ha observado que las supervivientes de cáncer de mama reducen la cantidad de ejercicio que realizan después de dichos tratamientos. Por ello, el objetivo de este proyecto es examinar los efectos de un programa integral de ejercicio en la calidad de vida y la cantidad de ejercicio físico que realizan las pacientes con cáncer de mama en su tiempo, tras finalizar sus tratamientos. MATERIAL Y MÉTODOS Se diseñó un Ensayo Clínico Aleatorizado. Noventa pacientes diagnosticadas de cáncer de mama en estadios tempranos que habían terminado sus tratamientos de radioterapia y quimioterapia recientemente, fueron reclutadas por la Universidad Politécnica de Madrid, desde enero de 2013 hasta junio de 2014. Las pacientes fueron aleatorizadas tras las mediciones iniciales al grupo control (tratamientos habituales) o grupo intervención, durante tres meses. La intervención consistió en 24 clases de ejercicio combinando práctica aeróbica y de fuerza con el fin de reducir los efectos secundarios de dichos tratamientos. La calidad de vida, la cantidad de ejercicio físico realizado en tiempo de ocio, VO2max, la fuerza, la movilidad articular del hombro, la fatiga, la depresión y la ansiedad fueron medidos al inicio y después de los tres meses en todos los pacientes. RESULTADOS Un total de 89 pacientes con una media de 49.06±8.75 de edad fueron finalmente analizadas. El grupo intervención (n=44) mostraron significativamente mejores resultados en calidad de vida (p=0.0001; d=0.85), cantidad de ejercicio en tiempo de ocio (p=0.0001; d=2.77), en variables de la composición corporal, en variables físicas y en variables psicológicas comparado con el grupo control (n=45). Además, se observó una correlación significativa entre la calidad de vida y el ejercicio realizado en tiempo de ocio en el grupo intervención (r= 0.58; p=0.001), que no fue patente en el grupo control. Se observaron cambios significativos en el grupo de intervención relativos a la composición corporal, con aumento de la masa muscular (p=0.001) y reducción de la masa grasa (p=0.0001). Tanto las variables físicas como psicológicas también mostraron diferencias significativas a favor al grupo de intervención en las comparaciones entre grupos. CONCLUSIONES Según estos resultados, un programa de ejercicio físico específico es una intervención integral que mejora los hábitos y la calidad de vida de las supervivientes de cáncer de mama, lo que reduce determinados efectos secundarios de los tratamientos y aumenta la salud física y psicológica general de estas mujeres. Este tipo de intervenciones pude ser una herramienta barata y efectiva para ofrecer a los pacientes, integrada en los tratamientos habituales. ABSTRACT INTRODUCTION It is well known that breast cancer survivors are living longer. However, breast cancer treatments present serious side effects, which could affect breast cancer survivors’ (BCS) health and quality of life (QoL). Exercise has been presented as a feasible, safe and effective tool in reducing some of these side effects and to improve survivors’ QoL, acting as an integrative treatment for them, although it has been observed that BCS reduce their leisure time exercise (LTE) levels. Therefore, the aim of this study was to examine the effects of an integrative exercise program in QoL and LTE in BCS after the completion of their adjuvant treatment. MATERIAL AND METHODS A randomized controlled trial (RCT) was designed. Ninety patients diagnosed with an early stage of breast cancer and who recently finished chemotherapy and radiotherapy treatments were recruited by the Technical University of Madrid from January 2013 to June 2014. Patients were randomized after baseline assessments to the intervention group (IG) or to the control group (CG) (usual care) for three months. The Intervention consisted in 24 supervised exercise classes, combining aerobic and resistance exercises in order to reduce the most common side effects of the treatments. QoL, LTE, body composition, VO2max, strength, shoulder range of motion, fatigue, depression and self-esteem were measured in all the patients at baseline and after three months. RESULTS A total of 89 patients aged 49.06±8.75 years were finally assessed. IG (n=44) showed significant better results in QoL (p=0.0001; d=0.85), LTE (p=0.0001; d=2.77), in body composition, in the physical variable and in psychological outcomes, compared with the CG (n=45). In addition, a correlation between QoL and LTE (r= 0.58; p=0.001) was found in the IG, while CG did not show this correlation. Significant changes in body composition were observed in the group comparisons, especially in lean mass (p=0.001) and body fat mass (p= 0.0001). Positive changes were also observed in the physical and psychological variables in comparisons between groups. CONCLUSIONS These results suggest that this exercise program may be an integrative intervention, which is able to improve QoL and LTE levels in breast cancer survivors, reducing breast cancer side effects of treatments and improving their physical and psychological general health. Exercise may be an effective and inexpensive strategy to be included in patients integrative care.

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Some evidence shows that the rate of perceived exertion of one session (RPE-S) and fatigue (Fat) of athletes can be decreased by the intake of carbohydrates (HCO) during exercise. However, it is well known that professional athletes do not meet nutritional recommendations (NR) but a long term nutritional intervention (NI) can improve their dietary intake (DI). What is not known is whether these long-term changes in DI can influence RPE-S and Fat of training. Our aim was to conduct a long term NI to adapt the DI of one professional basketball player to current NR and evaluate the influence of these changes on long-term RPE and Fat.

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El presente trabajo consistió en el desarrollo de una intervención nutricional a largo plazo llevada a cabo con jugadores profesionales de baloncesto, en función al cumplimiento de las recomendaciones nutricionales, con los siguientes dos objetivos: 1) valorar los cambios que dicha intervención produce sobre las prácticas nutricionales diarias de estos deportistas y 2) conocer la influencia de las modificaciones nutricionales producidas sobre la tasa de percepción del esfuerzo por sesión (RPE-Sesión) y la fatiga, a lo largo de una temporada competitiva, tanto para entrenamientos como partidos oficiales. Los objetivos del estudio se fundamentan en: 1) la numerosa evidencia científica que muestra la inadecuación de los hábitos nutricionales de los jugadores de baloncesto y otros deportistas respecto a las recomendaciones nutricionales; 2) el hecho ampliamente reconocido en la literatura especializada de que una ingesta nutricional óptima permite maximizar el rendimiento deportivo (a nivel físico y cognitivo), promoviendo una rápida recuperación y disminuyendo el riesgo de enfermedades y lesiones deportivas. No obstante, pocos estudios han llevado a cabo una intervención nutricional a largo plazo para mejorar los hábitos alimentarios de los deportistas y ninguno de ellos fue realizado con jugadores de baloncesto; 3) la elevada correlación entre la percepción del esfuerzo (RPE) y variables fisiológicas relacionadas al desarrollo de un ejercicio (por ej.: frecuencia cardíaca, consumo máximo de oxígeno o lactato sanguíneo) y los múltiples estudios que muestran la atenuación de la RPE durante la realización del ejercicio mediante una ingesta puntual de nutrientes, (especialmente de hidratos de carbono) aunque ninguno fue desarrollado en baloncesto; 4) el estudio incipiente de la relación entre la ingesta nutricional y la RPE-Sesión, siendo éste un método validado en baloncesto y otros deportes de equipo como indicador de la carga de trabajo interna, el rendimiento deportivo y la intensidad del ejercicio realizado; 5) el hecho de que la fatiga constituye uno de los principales factores influyentes en la percepción del esfuerzo y puede ser retrasada y/o atenuada mediante la ingesta de carbohidratos, pudiendo disminuir consecuentemente la RPE-Sesión y la carga interna del esfuerzo físico, potenciando el rendimiento deportivo y las adaptaciones inducidas por el entrenamiento; 6) la reducida evidencia acerca del comportamiento de la RPE-Sesión ante la modificación de la ingesta de nutrientes, encontrándose sólo un estudio llevado a cabo en baloncesto y 7) la ausencia de investigaciones acerca de la influencia que puede tener la mejora del patrón nutricional de los jugadores sobre la RPE-Sesión y la fatiga, desconociéndose si la adecuación de los hábitos nutricionales conduce a una disminución de estas variables en el largo plazo para todos los entrenamientos y partidos oficiales a nivel profesional. Por todo esto, este trabajo comienza con una introducción que presenta el marco teórico de la importancia y función de la nutrición en el deporte, así como de las recomendaciones nutricionales actuales a nivel general y para baloncesto. Además, se describen las intervenciones nutricionales llevadas a cabo previamente con otros deportistas y las consecuentes modificaciones sobre el patrón alimentario, coincidiendo este aspecto con el primer objetivo del presente estudio. Posteriormente, se analiza la RPE, la RPE-Sesión y la fatiga, focalizando el estudio en la relación de dichas variables con la carga de trabajo físico, la intensidad del entrenamiento, el rendimiento deportivo y la recuperación post ejercicio. Finalmente, se combinan todos los aspectos mencionados: ingesta nutricional, RPE percepción del esfuerzo y fatiga, con el fin de conocer la situación actual del estudio de la relación entre dichas variables, conformando la base del segundo objetivo de este estudio. Seguidamente, se exponen y fundamentan los objetivos antes mencionados, para dar lugar después a la explicación de la metodología utilizada en el presente estudio. Ésta consistió en un diseño de estudios de caso, aplicándose una intervención nutricional personalizada a tres jugadores de baloncesto profesional (cada jugador = un estudio de caso; n = 1), con el objetivo de adecuar su ingesta nutricional en el largo plazo a las recomendaciones nutricionales. A su vez, se analizó la respuesta individual de cada uno de los casos a dicha intervención para los dos objetivos del estudio. Para ello, cada jugador completó un registro diario de alimentos (7 días; pesada de alimentos) antes, durante y al final de la intervención. Además, los sujetos registraron diariamente a lo largo del estudio la RPE-Sesión y la fatiga en entrenamientos físicos y de balón y en partidos oficiales de liga, controlándose además en forma cuantitativa otras variables influyentes como el estado de ánimo y el sueño. El análisis de los datos consistió en el cálculo de los estadísticos descriptivos para todas las variables, la comparación de la ingesta en los diferentes momentos evaluados con las recomendaciones nutricionales y una comparación de medias no paramétrica entre el período pre intervención y durante la intervención con el test de Wilcoxon (medidas repetidas) para todas las variables. Finalmente, se relacionaron los cambios obtenidos en la ingesta nutricional con la percepción del esfuerzo y la fatiga y la posible influencia del estado de ánimo y el sueño, a través de un estudio correlacional (Tau_b de Kendall). Posteriormente, se presentan los resultados obtenidos y la discusión de los mismos, haciendo referencia a la evidencia científica relacionada que se encuentra publicada hasta el momento, la cual facilitó el análisis de la relación entre RPE-Sesión, fatiga y nutrición a lo largo de una temporada. Los principales hallazgos y su correspondiente análisis, por lo tanto, pueden resumirse en los siguientes: 1) los tres jugadores de baloncesto profesional presentaron inicialmente hábitos nutricionales inadecuados, haciendo evidente la necesidad de un nutricionista deportivo dentro del cuerpo técnico de los equipos profesionales; 2) las principales deficiencias correspondieron a un déficit pronunciado de energía e hidratos de carbono, que fueron reducidas con la intervención nutricional; 3) la ingesta excesiva de grasa total, ácidos grasos saturados, etanol y proteínas que se halló en alguno/s de los casos, también se adecuó a las recomendaciones después de la intervención; 4) la media obtenida durante un período de la temporada para la RPE-Sesión y la fatiga de entrenamientos, podría ser disminuida en un jugador individual mediante el incremento de su ingesta de carbohidratos a largo plazo, siempre que no existan alteraciones psico-emocionales relevantes; 5) el comportamiento de la RPE-Sesión de partidos oficiales no parece estar influido por los factores nutricionales modificados en este estudio, dependiendo más de la variación de elementos externos no controlables, intrínsecos a los partidos de baloncesto profesional. Ante estos resultados, se pudo observar que las diferentes características de los jugadores y las distintas respuestas obtenidas después de la intervención, reforzaron la importancia de utilizar un diseño de estudio de casos para el análisis de los deportistas de élite y, asimismo, de realizar un asesoramiento nutricional personalizado. Del mismo modo, la percepción del esfuerzo y la fatiga de cada jugador evolucionaron de manera diferente después de la intervención nutricional, lo cual podría depender de las diferentes características de los sujetos, a nivel físico, psico-social, emocional y contextual. Por ello, se propone que el control riguroso de las variables cualitativas que parecen influir sobre la RPE y la fatiga a largo plazo, facilitaría la comprensión de los datos y la determinación de factores desconocidos que influyen sobre estas variables. Finalmente, al ser la RPE-Sesión un indicador directo de la carga interna del entrenamiento, es decir, del estrés psico-fisiológico experimentado por el deportista, la posible atenuación de esta variable mediante la adecuación de los hábitos nutricionales, permitiría aplicar las cargas externas de entrenamiento planificadas, con menor estrés interno y mejor recuperación entre sesiones, disminuyendo también la sensación de fatiga, a pesar del avance de la temporada. ABSTRACT This study consisted in a long-term nutritional intervention carried out with professional basketball players according to nutritional recommendations, with the following two main objectives: 1) to evaluate the changes produced by the intervention on daily nutritional practices of these athletes and 2) to determine the influence of long term nutritional intake modifications on the rate of perceived exertion per session (Session-RPE) and fatigue, throughout a competitive season for training as well as competition games. These objectives are based on: 1) much scientific evidence that shows an inadequacy of the nutritional habits of basketball players and other athletes regarding nutritional recommendations; 2) the fact widely recognized in the scientific literature that an optimal nutrition allows to achieve the maximum performance of an athlete (both physically and cognitively), promoting fast recovery and decreasing risks of sports injuries and illnesses. However, only few studies carried out a long term nutritional intervention to improve nutritional practices of athletes and it could not be found any research with basketball players; 3) the high correlation between the rate of perceived exertion (RPE) and physiological variables related to the performance of physical exercise (e.g.: heart rate, maximum consumption of oxygen or blood lactate) and multiple studies showing the attenuation of RPE during exercise due to the intake of certain nutrients (especially carbohydrates), while none of them was developed in basketball; 4) correlation between nutritional intake and Session-RPE has been recently studied for the first time. Session-RPE method has been validated in basketball players and other team sports as an indicator of internal workload, sports performance and exercise intensity; 5) fatigue is considered one of the main influential factor on RPE and sport performance. It has also been observed that carbohydrates intake may delay or mitigate the onset of fatigue and, thus, decrease the perceived exertion and the internal training load, which could improve sports performance and training-induced adaptations; 6) there are few studies evaluating the influence of nutrient intake on Session-RPE and only one of them has been carried out with basketball players. Moreover, it has not been analyzed the possible effects of the adequacy of players’ nutritional habits through a nutritional intervention on Session-RPE and fatigue, variables that could be decreased for all training session and competition games because of an improvement of daily nutritional intake. Therefore, this work begins with an introduction that provides the conceptual framework of this research focused on the key role of nutrition in sport, as well as on the current nutritional recommendations for athletes and specifically for basketball players. In addition, previous nutritional interventions carried out with other athletes are described, as well as consequential modifications on their food pattern, coinciding with the first objective of the present study. Subsequently, RPE, Session-RPE and fatigue are analyzed, with focus on their correlation with physical workload, training intensity, sports performance and recovery. Finally, all the aforementioned aspects (nutritional intake, RPE and fatigue) were combined in order to know the current status of the relation between each other, this being the base for the second objective of this study. Subsequently, the objectives mentioned above are explained, continuing with the explanation of the methodology used in the study. The methodology consisted of a case-study design, carrying out a long term nutritional intervention with three professional basketball players (each player = one case study; n = 1), in order to adapt their nutritional intake to nutritional recommendations. At the same time, the individual response of each player to the intervention was analyzed for the two main objectives of the study. Each player completed a food diary (7 days; weighing food) in three moments: before, during and at the end of the intervention. In addition, the Session-RPE and fatigue were daily recorded throughout the study for all trainings (training with ball and resistance training) and competition games. At the same time, other potentially influential variables such as mood state and sleeping were daily controlled throughout the study. Data analysis consisted in descriptive statistics calculation for all the variables of the study, the comparison between nutritional intake (evaluated at different times) and nutritional recommendations and a non-parametric mean comparison between pre intervention and during intervention periods was made by Wilcoxon test (repeated measurements) for all variables too. Finally, the changes in nutritional intake, mood state and sleeping were correlated with the perceived exertion and fatigue through correctional study (Tau_b de Kendall). After the methodology, the study results and the associated discussion are presented. The discussion is based on the current scientific evidence that contributes to understand the relation between Session-RPE, fatigue and nutrition throughout the competitive season. The main findings and results analysis can be summarized as follows: 1) the three professional basketball players initially had inadequate nutritional habits and this clearly shows the need of a sports nutritionist in the coaching staff of professional teams; (2) the major deficiencies of the three players’ diet corresponded to a pronounced deficit of energy intake and carbohydrates consumption which were reduced with nutritional intervention; (3) the excessive intake of total fat, saturated fatty acids, ethanol and protein found in some cases were also adapted to the recommendations after the intervention; (4) Session-RPE mean and fatigue of a certain period of the competition season, could be decreased in an individual player by increasing his carbohydrates intake in the long term, if there are no relevant psycho-emotional disorders; (5) the behavior of the Session-RPE in competition games does not seem to be influenced by the nutritional factors modified in this study. They seem to depend much more on the variation of external non-controllable factors associated with the professional basketball games. Given these results, the different characteristics of each player and the diverse responses observed after the intervention in each individual for all the variables, reinforced the importance of the use of a case study design for research with elite athletes as well as personalized nutritional counselling. In the same way, the different responses obtained for RPE and fatigue in the long term for each player due to modification of nutritional habits, show that there is a dependence of such variables on the physical, psychosocial, emotional and contextual characteristics of each player. Therefore it is proposed that the rigorous control of the qualitative variables that seem to influence the RPE and fatigue in the long term, may facilitate the understanding of data and the determination of unknown factors that could influence these variables. Finally, because Session-RPE is a direct indicator of the internal load of training (psycho-physiological stress experienced by the athlete), the possible attenuation of Session-RPE through the improvement in nutritional habits, would allow to apply the planned external loads of training with less internal stress and better recovery between sessions, with a decrease in fatigue, despite of the advance of the season.

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Introducción: El informe emitido por la Agencia Europea de Seguridad Alimentaria (EFSA) en 2010 sobre las declaraciones nutricionales y propiedades saludables, muestra que no existen evidencias científicas que apoyen la suplementación con aminoácidos ramificados (BCAAs). El objetivo de este estudio es analizar los efectos del consumo de suplementos de BCAAs en deportes de larga duración (DLD). Métodos: Estudio descriptivo de revisión bibliográfica sobre el estado actual del efecto del consumo de suplementos de BCAAs. Se realizó una búsqueda en la base de datos PubMed y estrategia de bola de nieve. Criterios de inclusión: Estudios realizados en humanos, ensayos clínicos controlados aleatorizados (ECCA) en castellano/inglés relacionados con el consumo de BCAAs, leucina, valina e isoleucina en DLD y sus efectos sobre el daño muscular, rendimiento deportivo, fatiga central, respuesta anabólica y sistema inmunológico publicados en cualquier país hasta mayo 2014. Resultados: De los 330 estudios identificados, 14 cumplieron los criterios de inclusión. La media de sujetos participantes en los estudio es igual a (11,36 ± 7,43). Sólo dos estudios incluyen un grupo de mujeres. Las disciplinas deportivas que se encontraron en los estudios fueron carrera a pie, ciclismo, combinación ciclismo y carrera a pie, triatlón distancia olímpica y un estudio que incluía 2 grupos de deportistas (triatlón distancia olímpica y carrera a pie). Se estudian los efectos de los BCAAs y daño muscular, rendimiento deportivo, fatiga central, respuesta anabólica en periodo de recuperación y respuesta inmunológica en periodos diferentes del entrenamiento: antes, durante y después o una combinación de éstos. Discusión: Se observa que existe un menor grado de dolor y daño muscular, menor percepción del esfuerzo y fatiga mental, mayor respuesta anabólica en periodo de recuperación y mejora de la respuesta inmunológica cuando se suplementa con BCAAs, no obstante su toma antes o durante la actividad física no mejora el rendimiento deportivo. No se ha encontrado consenso en la dosis y cronología de la toma más eficaz, aunque es más efectivo si hay una relación 2-3/1/1g, entre los aminoácidos Leucina/ Isoleucina y Valina.

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"July 1997."

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An important functional and evolutionary constraint on the physical performance of vertebrates is believed to be the trade-off between speed and endurance capacity. However, despite the pervasiveness of physiological arguments, most studies have found no evidence of the trade-off when tested at the whole-animal level. We investigated the existence of this trade-off at the whole-muscle level, the presumed site of this physiological conflict, by examining inter-individual variation in both maximum power output and fatigue resistance for mouse extensor digitorum longus (EDL) muscle using the work-loop technique. We found negative correlations between several measures of in vitro maximum power output and force production with fatigue resistance for individual mouse EDL muscles, indicating functional trade-offs between these performance parameters. We suggest that this trade-off detected at the whole-muscle level has imposed an important constraint on the evolution of vertebrate physical performance.