The Professional Level and its Impact on Muscle Mechanical and Functional Performance in Costa Rican Soccer Players / Nivel profesional e impacto en el desempeño mecánico y funcional muscular en los jugadores de fútbol de Costa Rica / Nível profissional e impacto no desempenho mecânico e funcional dos músculos dos jogadores de futebol da Costa Rica

Abstract: This study aimed to compare the mechanical and functional muscle performance of three different competitive soccer teams of the Costa Rica professional league (U17, Pro A, and Pro B). Age 20.09 ± 4.32 years old, weight body mass 70.85 ± 7.45 kg, height 174.56 ± 4.97 cm; body fat percentage 13.9 ± 5.06 %; lean body mass 57.90 ± 4.88 kg; lean body mass right lower limb 10.11 ± 0.87 kg; lean body mass leth lower limb 10.09 ± 0.92 kg. The variables assessed were muscle time of contraction, muscle radial displacement, delay time, squat jump, and countermovement jump. The devices used were dual ray absorptiometry, tensiomyography, and jump platform. There were differences in weight, body mass, and body fat % (Pro A< U17<Pro B). There was a difference in group squat jump performance (Pro A> U17). There were no significant differences in muscle time of contraction, delay time, or radial deformation. The knowledge of differences in both muscle functional and mechanical performance could lead to new training and recovery methods and protocols considering the player's professional levels.

Resumen: El objetivo de este estudio fue comparar el rendimiento muscular mecánico y funcional de tres equipos de fútbol competitivos diferentes de la liga profesional de Costa Rica (U17, Pro A, Pro B). Edad 20.09 ± 4.32 años, ; masa corporal 70.85 ± 7.45 kg, ; altura 174.56 ± 4.97 cm; porcentaje de grasa 13.9 ± 5.06 %; masa magra 57.90 ± 4.88 kg; masa magra extremidad inferior derecha 10.11 ± 0.87 kg; masa magra izquierda miembro inferior izquierdo 10.09 ± 0,92 kg. Las variables evaluadas fueron: tiempo de contracción muscular, desplazamiento radial del músculo, tiempo de retraso, salto en cuclillas y salto de contraataque. Los dispositivos utilizados fueron la absorciometría de doble rayo, la tensiomiografía y la plataforma de salto. Se encontraron diferencias en la masa corporal y la grasa. % (Pro A < U17 < Pro B). Hubo diferencias en el rendimiento del salto en sentadilla por grupos (Pro A > U17). No hubo diferencias significativas en el tiempo de contracción muscular, el tiempo de retraso o la deformación radial. El conocimiento de las diferencias en Ttanto en el rendimiento funcional como en el mecánico del músculo podría conducir a nuevos métodos y protocolos de entrenamiento y recuperación considerando los niveles profesionales del jugador.

Resumo: O objetivo deste estudo foi comparar o desempenho mecânico e funcional de três diferentes equipes de futebol competitivas da liga profissional costarriquenha (U17, Pro A, Pro B). Idade 20,09 ± 4,32 anos, massa corporal 70,85 ± 7,45 kg, altura 174,56 ± 4,97 cm; percentual de gordura 13,9 ± 5,06%; massa magra 57,90 ± 4,88 kg; massa magra extremidade inferior direita 10,11 ± 0,87 kg; massa magra membro inferior esquerdo 10,09 ± 0,92 kg. As variáveis avaliadas foram: tempo de contração muscular, deslocamento radial do músculo, tempo de atraso, salto de cócoras e contra salto. Os dispositivos utilizados foram a absorciometria por raios-X com dupla energia, a tensiomiografia e a plataforma de salto. Foram encontradas diferenças na massa corporal e na gordura. % (Pro A <U17 <Pro B). Houve diferenças no desempenho do salto de agachamento por grupo (Pro A> U17). Não foram encontradas diferenças significativas no tempo de contração muscular, tempo de atraso ou deformação radial. O conhecimento das diferenças tanto no desempenho muscular funcional quanto mecânico poderia levar a novos métodos e protocolos de treinamento e recuperação, considerando os níveis profissionais do jogador.

Wearable Sports Technology Development in Costa Rica: Inertial Measurement Unit Integration for Real-Time External Load Monitoring / Desarrollo de tecnología deportiva portátil en Costa Rica: integración de una unidad de medición inercial para monitoreo de carga externa en tiempo real / Desenvolvimento de tecnologia desportiva portátil na Costa Rica: integração de uma unidade de medição por inércia para monitorização da carga externa em tempo real

Abstract: The increasing trend and projection for the use of wearable sensors technology in the general population have led to the development of different inertial measurement units (IMU) to monitor activity and motion variables during exercise or sports. This study aims to systematize the practical experience of developing an inertial measurement device to quantify external load in real time for runners. This article shows the installed capacity of Costa Rican higher education institutions to integrate existing sensors available in the international market in a single device to program it and use it for different sport science purposes. Two scientific laboratories joined resources and integrated an interdisciplinary team composed of exercise physiologists, sports scientists, physiotherapists, and electromechanical engineers who globally faced the challenge of creating SafeRun IMU. In this case, an IMU was constructed with great success, capable of quantifying external load variables controlled from a mobile device in real-time. The results showed an acceptable agreement and reliability of the data extracted from the IMU. The information collected from this IMU could be used to control and quantify external load to develop or redirect exercise programming and prescription and prevent overuse injuries or physical overload conditions. This device differs from other existing ones due to its small size and portability, which benefits its commercialization and massification.

Resumen: La creciente tendencia y proyección para el uso de tecnología de sensores portátiles en la población en general ha llevado al desenvolvimiento de diferentes dispositivos de medición inercial, para monitorear las variables de actividad y movimiento durante el ejercicio o los deportes. El objetivo del presente estudio es sistematizar la experiencia práctica de desarrollar un dispositivo de medición inercial, con el fin de cuantificar la carga externa en tiempo real para los corredores. Este artículo demostró la capacidad instalada de las instituciones de educación superior de Costa Rica para integrar los sensores existentes disponibles en el mercado internacional en un solo dispositivo, con el propósito de programarlo y usarlo en diferentes fines de ciencias del deporte. Dos laboratorios científicos unieron esfuerzos e integraron un equipo interdisciplinario compuesto por fisiólogos del ejercicio, científicos del deporte, fisioterapeutas e ingenieros electromecánicos, quienes, de manera global, afrontaron el reto de la creación de la IMU. En este caso, se desarrolló una IMU con gran éxito, capaz de cuantificar las variables de carga externa controladas desde un dispositivo móvil en tiempo real. Los resultados mostraron un nivel de concordancia y fiabilidad aceptable de los datos extraídos de la IMU. La información obtenida de esta IMU podría usarse para controlar y cuantificar la carga externa, con miras a desplegar o redirigir la programación y prescripción de ejercicios, así como con el afán de prevenir lesiones por sobreuso o condiciones de sobrecarga física.

Resumo: A crescente tendência e projeção para o uso da tecnologia de sensores portáteis na população em geral levou ao desenvolvimento de diferentes dispositivos de medição inercial para monitorar as variáveis de atividade e de movimento durante o exercício ou esportes. O objetivo do presente estudo é sistematizar a experiência prática de desenvolvimento de um dispositivo de medição inercial, a fim de quantificar a carga externa em tempo real para os corredores. Este artigo demonstrou a capacidade instalada das instituições de ensino superior da Costa Rica para integrar os sensores existentes disponíveis no mercado internacional em um único dispositivo, com a finalidade de programá-lo e usá-lo para diferentes fins de ciência do esporte. Dois laboratórios científicos uniram forças e integraram uma equipe interdisciplinar composta por fisiologistas do exercício, cientistas do esporte, fisioterapeutas e engenheiros eletromecânicos, que, de forma global, enfrentaram o desafio de criar a IMU. Neste caso, foi desenvolvida uma IMU de grande sucesso, capaz de quantificar variáveis de carga externas controladas a partir de um dispositivo móvel em tempo real. Os resultados mostraram um nível aceitável de concordância e confiabilidade dos dados extraídos da IMU. As informações obtidas desta IMU poderiam ser utilizadas para monitorar e quantificar a carga externa, com o objetivo de implantar ou redirecionar a programação e prescrição de exercícios, bem como com o objetivo de evitar lesões por uso excessivo ou condições de sobrecarga física.

Análisis de los polimorfismos ECA y ACTN3 con la agilidad en seleccionados nacionales de deportes de conjunto de Costa Rica. Estudio piloto / ACE and ACTN3 polymorphisms analysis on agility test in national players in team sports of Costa Rica. Pilot study / Análise dos polimorfismos ECA e ACTN3 com agilidade em jogadores esportivos selecionados da seleção costarriquenha. Estudo piloto

Resumen: Objetivo: Analizar las diferencias de los polimorfismos de los genes ECA y ACTN3 en el rendimiento de una prueba de agilidad en jugadores élite de deportes colectivos pertenecientes a selecciones nacionales de Costa Rica. Metodología: Se contó con una muestra de 33 jugadores hombres, de deportes colectivos (fútbol sala, rugby, voleibol y balonmano). Para la evaluación de la agilidad se utilizó el test de Illinois. Se realizaron dos visitas, en la primera se obtuvo muestras de células por medio de un enjuague y en la segunda se aplicó la prueba de agilidad. Se utilizó la prueba de Chi-cuadrado (X2) para conocer las diferencias entre las frecuencias de los polimorfismos de los genes ECA y ACTN3 y el tipo de deporte. Resultados: La mayor distribución de los polimorfismos del gen ECA, de jugadores de selecciones nacionales de deportes de conjunto, se encuentra en el ID (X2= 6.87, p= .334) y en ACTN3 el RX (X2= 6.33, p= .388). Además, tampoco se encontraron diferencias significativas entre el tiempo efectuado en el test de Illinois y los polimorfismos del gen ECA (F= 2.150, p= .134), de igual forma para los polimorfismos del gen ACTN3 (F= .950, p= .339). Conclusiones: Los polimorfismos de los genes ECA y ACTN3 no se relacionaron estadísticamente con el tipo de deporte colectivo. La agilidad no se ve asociada por un tipo de polimorfismo, lo que indica que, de forma independiente al gen, esta cualidad física se puede entrenar y generar buenos resultados en la población en general.

Abstract: Objective: To analyze the differences in the polymorphisms of the ACE and ACTN3 genes on agility test performance in elite players of collective sports from National teams of Costa Rica. Methods: a sample of 33 male team sports players (futsal, rugby, volleyball, and handball). All subjects were tested with the Illinois Agility Test. Two days of measurements were made; on the first day, cell samples were obtained and on the second day, the agility test was applied. The Chi-square test (x2) was used to determine the differences between the frequencies of the polymorphisms of the ACE and ACTN3 genes and the type of sport. Results: The highest distribution of polymorphisms of the ECA gene of players from national teams of collective sports was found in the ACE ID (X2 = 6.87, p = .334), and in ACTN3 the RX (X2 = 6.33, p =. 388). Furthermore, no significant relationship was found between the Illinois test performance and the polymorphisms of the ECA gene (F = 2,150, p = .134). Conclusions: The ACE and ACTN3 genes polymorphisms were not statistically related to the type of team sport. Agility is not associated with the type of polymorphism, which indicates that regardless of the gene, this physical quality can be trained and generate good results in the general population.

Resumo: Objetivo: analisar as diferenças dos polimorfismos dos genes ECA e ACTN3 na realização de um teste de agilidade em jogadores de elite de equipes esportivas pertencentes a equipes nacionais costarriquenhas. Metodologia: foi utilizada uma amostra de 33 jogadores de futebol masculino (futsal, rúgbi, vôlei e handebol). O teste de Illinois foi usado para avaliar a agilidade. Foram feitas duas visitas; na primeira foram obtidas amostras de uma célula por lavagem e na segunda foi aplicado o teste de agilidade. O teste qui-quadrado (X2) foi usado para determinar as diferenças entre as frequências dos polimorfismos dos genes ECA e ACTN3 e o tipo de esporte. Resultados: A maior distribuição de polimorfismos do gene ECA em jogadores de equipes nacionais de esportes coletivos é encontrada no ID (X2= 6,87, p= 0,334) e no ACTN3 no RX (X2= 6,33, p= 0,388). Além disso, não foram encontradas diferenças significativas entre o tempo gasto no teste de Illinois e os polimorfismos do gene ECA (F= 2,150, p= 0,134), assim como para os polimorfismos do gene ACTN3 (F= 0,950, p= 0,339). Conclusões: Os polimorfismos dos genes ECA e ACTN3 não estavam estatisticamente relacionados com o tipo de esporte coletivo. A agilidade não está associada pelo tipo de polimorfismo, indicando que, independentemente do gene, essa qualidade física pode ser treinada e gerar bons resultados na população em geral.

Anthropometric, aerobic and muscle power profile of young Costa Rican basketball players / Perfil antropométrico, aeróbico y de potencia muscular de jugadores juveniles de baloncesto costarricenses

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. y Rojas-Valverde, D. (2022). Perfil antropométrico, aeróbico y de potencia muscular de jugadores juveniles de baloncesto costarricenses. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-17. El objetivo de este estudio fue describir un perfil antropométrico, aeróbico y de potencia muscular de basquetbolistas juveniles costarricenses según sexo, posiciones de juego y categoría de edad. Se evaluaron 99 jugadores juveniles (43 mujeres y 56 hombres; 18 bases, 51 aleros y 30 pívots; 42 categoría U16 y 57 categoría U18) de ocho equipos diferentes. La experiencia deportiva de los jugadores fue de 6.5 ± 3.1 años. Se realizaron las siguientes evaluaciones: altura, peso, índice de masa corporal, masa músculo-esquelética, porcentaje de grasa, prueba de contramovimiento (CMJ) y prueba de Yo-Yo de Recuperación Intermitente Nivel I. Los principales resultados mostraron valores significativamente mayores en hombres que en mujeres en peso, talla, masa músculo-esquelética, distancia recorrida en la prueba Yo-Yo, en el VO2max, altura en el CMJ y en el tiempo de vuelo. El porcentaje de grasa fue mayor en mujeres que en hombres. Los jugadores pívots presentaron significativamente mayor estatura, peso corporal y porcentaje de grasa que las otras posiciones de juego. Los bases y los aleros cubrieron más metros en la prueba Yo-Yo y tuvieron mayor VO2máx que los pívots. Entre las categorías U16 y U18 no se encontraron diferencias significativas en ninguna variable. Modelos de regresión mostraron la influencia del peso, porcentaje de grasa corporal, masa músculo esquelética y la edad sobre el VO2máx y CMJ. Como conclusión, según el sexo y las posiciones de juego de los jugadores, estos indicadores variaron. Además, esta información será útil para procesos de promoción, desarrollo y diseño de entrenamientos de baloncesto juvenil en Costa Rica.

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. e Rojas-Valverde, D. (2022). Perfil antropométrico, aeróbico e de potência muscular de jogadores juvenis de basquete da Costa Rica. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-17. Este estudo teve como objetivo descrever um perfil antropométrico, aeróbico e de potência muscular de jogadores juvenis de basquete da Costa Rica segundo o sexo, as posições de jogo e a categoria de idade. Foram avaliados 99 jogadores juvenis (43 mulheres e 56 homens; 18 armadores, 51 alas e 30 pivôs; 42 na categoria U16 e 57 na categoria U18) de oito equipes diferentes. A experiência esportiva dos jogadores foi de 6,5 ± 3,1 anos. Foram realizadas as seguintes avaliações: altura, peso, índice de massa corporal, massa musculoesquelética e porcentagem de gordura, teste de salto com contramovimento (SCM) e teste de Yo-Yo de Recuperação Intermitente Nível I. Os principais resultados mostraram valores significativamente maiores em homens do que em mulheres com relação ao peso, tamanho, massa muscular esquelética, distância percorrida no teste Yo-Yo, VO2max, altura no SCM e no tempo de voo. A porcentagem de gordura foi maior em mulheres do que em homens. Os jogadores pivôs apresentaram significativamente maior estatura, peso corporal e porcentagem de gordura do que as outras posições de jogo. Os armadores e os alas cobriram mais metros no teste Yo-Yo e tiveram maior VO2max do que os pivôs. Entre as categorias U16 e U18 não foram encontradas diferenças significativas em nenhuma variável. Modelos de regressão mostraram a influência do peso, da porcentagem de gordura corporal, da massa musculoesquelética e da idade no VO2max e SCM. Conclui-se, portanto, que esses indicadores variam segundo o sexo e as posições dos jogadores. Além disso, essa informação será útil para processos de fomentação, desenvolvimento e desenho de treinamentos de basquete juvenil na Costa Rica.

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. & Rojas-Valverde, D. (2022). Anthropometric, aerobic and muscle power profile of young Costa Rican basketball players. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 21(1), 1-17. The purpose of this study was to describe an anthropometric, aerobic and muscle power profile of young Costa Rican basketball players according to sex, play positions and age. The assessment was carried outa on 99 young players (43 women and 56 men; 18 guards, 51 forwards and 30 centers; 42 in the U16 category and 57 in the U18 category) from eight different teams. The sports experience of the players was 6.5 ± 3.1 years. The following parameters were assessed: height, weight, body mass index, skeletal muscle mass and body fat percentage, countermovement test (CMJ) and Yo-Yo Intermittent Recovery Test Level I. The main results showed significantly higher values in men than in women in terms of weight, height, skeletal muscle mass, distance covered in the yo-yo test, VO2max, height in CMJ and in flight time. Body fat percentage was higher in women than in men. Centers showed significantly higher height, weight and body fat percentage than other play positions. Guards and forwards covered more meters in the yo-yo test and showed higher VO2max than centers. No significant differences were found between the U16 and U18 categories in any variable. Regression models showed the influence of weight, body fat percentage, skeletal muscle mass and age on VO2max and CMJ. In conclusion, these indicators varied according to the sex and play position of the players. Additionally, this information will be useful for processes of promotion, development and training design of youth basketball in Costa Rica.

Anthropometric, aerobic and muscle power profile of young Costa Rican basketball players / Perfil antropométrico, aeróbico y de potencia muscular de jugadores juveniles de baloncesto costarricenses

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. & Rojas-Valverde, D. (2022). Anthropometric, aerobic and muscle power profile of young Costa Rican basketball players. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20(2), 1-15. The purpose of this study was to describe an anthropometric, aerobic and muscle power profile of young Costa Rican basketball players according to sex, play positions and age. The assessment was carried outa on 99 young players (43 women and 56 men; 18 guards, 51 forwards and 30 centers; 42 in the U16 category and 57 in the U18 category) from eight different teams. The sports experience of the players was 6.5 ± 3.1 years. The following parameters were assessed: height, weight, body mass index, skeletal muscle mass and body fat percentage, countermovement test (CMJ) and Yo-Yo Intermittent Recovery Test Level I. The main results showed significantly higher values in men than in women in terms of weight, height, skeletal muscle mass, distance covered in the yo-yo test, VO2max, height in CMJ and in flight time. Body fat percentage was higher in women than in men. Centers showed significantly higher height, weight and body fat percentage than other play positions. Guards and forwards covered more meters in the yo-yo test and showed higher VO2max than centers. No significant differences were found between the U16 and U18 categories in any variable. Regression models showed the influence of weight, body fat percentage, skeletal muscle mass and age on VO2max and CMJ. In conclusion, these indicators varied according to the sex and play position of the players. Additionally, this information will be useful for processes of promotion, development and training design of youth basketball in Costa Rica.

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. y Rojas-Valverde, D. (2022). Perfil antropométrico, aeróbico y de potencia muscular de jugadores juveniles de baloncesto costarricenses. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20(2), 1-15. El objetivo de este estudio fue describir un perfil antropométrico, aeróbico y de potencia muscular de basquetbolistas juveniles costarricenses según sexo, posiciones de juego y categoría de edad. Se evaluaron 99 jugadores juveniles (43 mujeres y 56 hombres; 18 bases, 51 aleros y 30 pívots; 42 categoría U16 y 57 categoría U18) de ocho equipos diferentes. La experiencia deportiva de los jugadores fue de 6.5 ± 3.1 años. Se realizaron las siguientes evaluaciones: altura, peso, índice de masa corporal, masa de músculo esquelética y porcentaje de grasa, prueba de contramovimiento (CMJ) y prueba de Yo-Yo de Recuperación Intermitente Nivel I. Los principales resultados mostraron valores significativamente mayores en hombres que en mujeres en peso, talla, masa muscular esquelética, distancia recorrida en la prueba Yo-Yo, VO2max, altura en el CMJ y en el tiempo de vuelo. El porcentaje de grasa fue mayor en mujeres que en hombres. Los jugadores pívots presentaron significativamente mayor estatura, peso corporal y porcentaje de grasa que las otras posiciones de juego. Los bases y los aleros cubrieron más metros en la prueba Yo-Yo y tuvieron mayor VO2max que los pívots. Entre las categorías U16 y U18 no se encontraron diferencias significativas en ninguna variable. Modelos de regresión mostraron la influencia del peso, porcentaje de grasa corporal, masa músculo esquelética y la edad sobre el VO2max y CMJ. Como conclusión, según el sexo y las posiciones de juego de los jugadores, estos indicadores variaron. Además, esta información será útil para procesos de promoción, desarrollo y diseño de entrenamientos de baloncesto juvenil en Costa Rica.

Gutiérrez-Vargas, R., Ugalde-Ramírez, A., Pino-Ortega, J., Trejos-Montoya, J.A., Blanco-Romero, L., Sánchez-Ureña, B., Gutiérrez-Vargas, J.C. e Rojas-Valverde, D. (2022). Perfil antropométrico, aeróbico e de potência muscular de jogadores juvenis de basquete da Costa Rica. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20(2), 1-15. Este estudo teve como objetivo descrever um perfil antropométrico, aeróbico e de potência muscular de jogadores juvenis de basquete da Costa Rica segundo o sexo, as posições de jogo e a categoria de idade. Foram avaliados 99 jogadores juvenis (43 mulheres e 56 homens; 18 armadores, 51 alas e 30 pivôs; 42 na categoria U16 e 57 na categoria U18) de oito equipes diferentes. A experiência esportiva dos jogadores foi de 6,5 ± 3,1 anos. Foram realizadas as seguintes avaliações: altura, peso, índice de massa corporal, massa musculoesquelética e porcentagem de gordura, teste de salto com contramovimento (SCM) e teste de Yo-Yo de Recuperação Intermitente Nível I. Os principais resultados mostraram valores significativamente maiores em homens do que em mulheres com relação ao peso, tamanho, massa muscular esquelética, distância percorrida no teste Yo-Yo, VO2max, altura no SCM e no tempo de voo. A porcentagem de gordura foi maior em mulheres do que em homens. Os jogadores pivôs apresentaram significativamente maior estatura, peso corporal e porcentagem de gordura do que as outras posições de jogo. Os armadores e os alas cobriram mais metros no teste Yo-Yo e tiveram maior VO2max do que os pivôs. Entre as categorias U16 e U18 não foram encontradas diferenças significativas em nenhuma variável. Modelos de regressão mostraram a influência do peso, da porcentagem de gordura corporal, da massa musculoesquelética e da idade no VO2max e SCM. Conclui-se, portanto, que esses indicadores variam segundo o sexo e as posições dos jogadores. Além disso, essa informação será útil para processos de fomentação, desenvolvimento e desenho de treinamentos de basquete juvenil na Costa Rica.

Pesticide exposure and cortical brain activation among farmworkers in Costa Rica.

BACKGROUND: Previous epidemiological studies have reported associations of pesticide exposure with poor cognitive function and behavioral problems. However, these findings have relied primarily on neuropsychological assessments. Questions remain about the neurobiological effects of pesticide exposure, specifically where in the brain pesticides exert their effects and whether compensatory mechanisms in the brain may have masked pesticide-related associations in studies that relied purely on neuropsychological measures. METHODS: We conducted a functional neuroimaging study in 48 farmworkers from Zarcero County, Costa Rica, in 2016. We measured concentrations of 13 insecticide, fungicide, or herbicide metabolites or parent compounds in urine samples collected during two study visits (approximately 3-5 weeks apart). We assessed cortical brain activation in the prefrontal cortex during tasks of working memory, attention, and cognitive flexibility using functional near-infrared spectroscopy (fNIRS). We estimated associations of pesticide exposure with cortical brain activation using multivariable linear regression models adjusted for age and education level. RESULTS: We found that higher concentrations of insecticide metabolites were associated with reduced activation in the prefrontal cortex during a working memory task. For example, 3,5,6-trichloro-2-pyridinol (TCPy; a metabolite of the organophosphate chlorpyrifos) was associated with reduced activation in the left dorsolateral prefrontal cortex (ß = -2.3; 95% CI: -3.9, -0.7 per two-fold increase in TCPy). Similarly, 3-phenoxybenzoic acid (3-PBA; a metabolite of pyrethroid insecticides) was associated with bilateral reduced activation in the dorsolateral prefrontal cortices (ß = -3.1; 95% CI: -5.0, -1.2 and -2.3; 95% CI: -4.5, -0.2 per two-fold increase in 3-PBA for left and right cortices, respectively). These associations were similar, though weaker, for the attention and cognitive flexibility tasks. We observed null associations of fungicide and herbicide biomarker concentrations with cortical brain activation during the three tasks that were administered. CONCLUSION: Our findings suggest that organophosphate and pyrethroid insecticides may impact cortical brain activation in the prefrontal cortex - neural dynamics that could potentially underlie previously reported associations with cognitive and behavioral function. Furthermore, our study demonstrates the feasibility and utility of fNIRS in epidemiological field studies.

Kidney Function in Rice Workers Exposed to Heat and Dehydration in Costa Rica.

The aim of this study was to evaluate heat exposure, dehydration, and kidney function in rice workers over the course of three months, in Guanacaste, Costa Rica. We collected biological and questionnaire data across a three-month-period in male field (n = 27) and other (n = 45) workers from a rice company where chronic kidney disease of unknown origin (CKDu) is endemic. We used stepwise forward regression to determine variables associated with estimated glomerular filtration rate eGFR at enrollment and/or change in eGFR, and Poisson regression to assess associations with incident kidney injury (IKI) over the course of three months. Participants were 20−62 years old (median = 40 in both groups). Dehydration was common (≥37%) in both groups, particularly among other workers at enrollment, but field workers were more exposed to heat and had higher workloads. Low eGFR (<60 mL/min/1.73 m2) was more prevalent in field workers at enrollment (19% vs. 4%) and follow-up (26% vs. 7%). Field workers experienced incident kidney injury (IKI) more frequently than other workers: 26% versus 2%, respectively. Age (ß = −0.71, 95%CI: −1.1, −0.4), current position as a field worker (ß = −2.75, 95%CI: −6.49, 0.99) and past work in construction (ß = 3.8, 95%CI: −0.1, 7.6) were included in the multivariate regression model to explain eGFR at enrollment. The multivariate regression model for decreased in eGFR over three month included current field worker (ß = −3.9, 95%CI: −8.2, 0.4), current smoking (ß= −6.2, 95%CI: −13.7−1.3), dehydration (USG ≥ 1.025) at both visits (ß= −3.19, 95%CI: −7.6, 1.2) and pain medication at follow-up (ß= −3.2, 95%CI: −8.2, 1.95). Current fieldwork [IR (incidence rate) = 2.2, 95%CI 1.1, 5.8) and being diabetic (IR = 1.8, 95%CI 0.9, 3.6) were associated with IKI. Low eGFR was common in field workers from a rice company in Guanacaste, and being a field worker was a risk factor for IKI, consistent with the hypothesis that occupational heat exposure is a critical risk factor for CKDu in Mesoamerica.

ACTN-3 and ECA genes expression do not influence the acute change in muscle mechanical and functional properties in youth handballers / Expresiones de los genes ACTN-3 y ECA no influyen en el cambio agudo de las propiedades musculares mecánicas y funcionales en jugadores juveniles de balonmano

The purpose of this study was to explore the potential relationship between ACTN-3 and ACE gene expression over the change in muscle mechanical and functional properties in youth handballers through a congested tournament. 30 players of the first handball division of Costa Rica participated in this study. The participants played a national tournament during three consecutive days (one match per day). The collection of genetic samples was through a mouth rinse with a 5% sucrose solution before the tournament. PCR tests were used to detect the alleles of the ACE and ACTN3 genes and the product ́s reaction was visualized by electrophoresis. Before and after each match, tensiomyography (TMG) and Countermovement jump (CMJ) tests were used to assess mechanical and functional properties respectively. Descriptive frequency analyses and a one-way analysis of variance of independent groups were the statistics test applied. The results showed that the most prevalent polymorphisms expression was ACTN-3 R-X (56.7%) and ECA I-D (43.3%). No significant differences (p> 0.050) were found between genes expressed in the mechanical responses (contraction time (TC), delay time (TD) and, maximum radial displacement (DM)) of the rectus femoral muscle of the dominant leg neither in performance in the test CMJ. Likewise, there was no significant change (p> 0.050) in muscle mechanical or functional properties post official matches. In conclusion, handball players have the genes ACE and ACTN. Nevertheless, it seems to have no influence of these genes on the mechanical or functional muscles acute responses. More investigations will be needed to explain and understand the real impact of this gene’s expression on muscle performance in handball players.(AU)

El propósito de este estudio fue explorar la relación potencial entre la expresión ACTN-3 y ACE sobre el cambio en las propiedades musculares mecánicas y funcionales de jugadores juveniles de balonmano a través de un torneo congestionado. Participaron 30 jugadores de la primera división de balonmano de Costa Rica. Los participantes jugaron un torneo nacional durante tres días consecutivos. La recolección de muestras genéticas se realizó mediante un enjuague bucal con una solución de sacarosa al 5% antes del inicio del torneo. Pruebas de PCR fueron usadas para detectar los aleros de los genes ACTN-3 y ACE y la reacción del producto fueron visualizadas por electroforesis. Antes y después de cada partido, se utilizaron las pruebas de tensiomiografía (TMG) y de salto contramovimiento (CMJ) para evaluar las propiedades mecánicas y funcionales respectivamente. Las pruebas estadísticas aplicadas fueron análisis descriptivo de frecuencias y un análisis de varianza de una vía para grupos independientes. Los resultados mostraron que la expresión de polimorfismos más prevalente fue ACTN-3 R-X (56,7%) y ECA I-D (43,3%). No se han encontrado diferencias significativas (p> 0,050) entre genes expresados en las respuestas mecánicas (tiempo de contracción (TC), tiempo de retardo (TD) and, máximo desplazamiento radial (DM)) del músculo recto femoral de la pierna dominante ni en el rendimiento en la prueba de CMJ. Asimismo, no hubo cambios significativos (p>0.050) en las propiedades mecánicas o funcionales de los músculos después de los partidos. En conclusión, los jugadores de balonmano tienen los genes ACE y ACTN, sin embargo, parece que estos genes no influyen en las respuestas agudas mecánicas o funcionales de los músculos. Se necesitan más investigaciones para explicar y comprender el impacto real de la expresión de estos genes en el rendimiento muscular de los jugadores de balonmano.(AU)

Short-Term Skin Temperature Responses to Endurance Exercise: A Systematic Review of Methods and Future Challenges in the Use of Infrared Thermography.

BACKGROUND: Body temperature is often assessed in the core and the skin. Infrared thermography has been used to measure skin temperature (Tsk) in sport research and clinical practice. This study aimed to explore the information reported to date on the use of infrared thermography to detect short-term Tsk responses to endurance exercise and to identify the methodological considerations and knowledge gaps, and propose future directions. METHOD: A web search (PubMed, Science Direct, Google Scholar, and Web of Science) was conducted following systematic review guidelines, and 45 out of 2921 studies met the inclusion criteria (endurance sports, since 2000, English, full text available). RESULTS: A total of 45 publications were extracted, in which most of the sample were runners (n = 457, 57.9%). Several differences between IRT imaging protocols and ROI selection could lead to potential heterogeneity of interpretations. These particularities in the methodology of the studies extracted are widely discussed in this systematic review. CONCLUSIONS: More analyses should be made considering different sports, exercise stimuli and intensities, especially using follow-up designs. Study-derived data could clarify the underlying thermo physiological processes and assess whether Tsk could be used a reliable proxy to describe live thermal regulation in endurance athletes and reduce their risk of exertional heat illness/stroke. Also more in-depth analyses may elucidate the Tsk interactions with other tissues during exercise-related responses, such as inflammation, damage, or pain.

Demandas físicas de jugadores profesionales costarricenses de fútbol: Influencia de la posición de juego y nivel competitivo / Physical Demands of Costa Rican Professional Soccer Players: Influence of the Playing Position and the Competitive Level

Resumen La monitorización de las demandas físicas durante partidos de fútbol con tecnologías GPS proporciona información valiosa que puede ser utilizada para potenciar el rendimiento deportivo. Por tanto, el objetivo de este estudio fue conocer las demandas físicas de jugadores profesionales costarricenses de fútbol, así como analizar la influencia de la posición de juego y el nivel competitivo durante partidos. Sesenta futbolistas masculinos, 50 de la primera división del fútbol costarricense y 10 de una selección nacional absoluta de CONCACAF (SAC), fueron monitoreados con un Sistema de Posicionamiento Global (GPS) para cuantificar variables cinemáticas como la distancia recorrida (m), total y a diferentes intensidades (Z 1-5), velocidad máxima (km/h), impactos totales (g), aceleraciones (m/s) y desaceleraciones (m/s). Las posiciones de juego se categorizaron en: defensas (Def), mediocampistas (Med) y delanteros (Del), y el nivel competitivo en: a) SAC, b) Equipos de nivel élite (ENE) y c) Equipos de nivel sub-élite (ENS). Los resultados reflejaron diferencias significativas respecto al nivel competitivo en la distancia recorrida a diferentes intensidades Z1 (SAC >ENS >ENE), Z2 (ENE >SAC >ENS) y Z4 (ENE >SAC >ENS), aceleraciones (SAC >ENE >ENS) y en desaceleraciones (SAC >ENS >ENE). Por posiciones de juego, las diferencias estuvieron en la distancia total (Med >Def >Del), en la distancia recorrida en Z2 (Med >Def >Del) y Z3 (Med >Def >Del), así como en impactos totales (Med >Def >Del). Se concluye que el nivel competitivo influye sobre las demandas físicas. SAC registró más aceleraciones y desaceleraciones y, ENE recorrió mayor distancia a esfuerzos moderados e intensos. Existen diferencias en las posiciones de juego, los mediocampistas recorrieron mayores distancias y registraron más impactos.

Abstract Monitoring physical demands during soccer matches with GPS technologies provides valuable information that can be used to enhance sports performance. Therefore, this study aimed to know Costa Rican professional soccer players' physical demands and analyze the influence of the playing position and the competitive level during matches. Sixty male soccer players, 50 from the first division of Costa Rican soccer and 10 from an absolute national CONCACAF (SAC) team were monitored with a Global Positioning System (GPS) to quantify kinematic variables such as distance traveled (m), total and different intensities (Z 1-5), maximum speed (km/h), total impacts (g), accelerations (m / s) and decelerations (m/s). The game positions were categorized into defenses (Def), midfielders (Mid) and forward (For), and the competitive level in a) SAC, b) Elite level teams (ENE), and c) Sub-elite level teams (ENS). The results reflected significant differences regarding the competitive level in the distance traveled at different intensities Z1 (SAC >ENS >ENE), Z2 (ENE >SAC >ENS) and Z4 (ENE >SAC >ENS), in accelerations (SAC >ENE >ENS), and in decelerations (SAC >ENS >ENE). By game positions, the differences were in the total distance (Mid >Def >For), in the distance traveled in Z2 (Mid >Def >For) and Z3 (Mid >Def >For), as well as in total impacts (Mid >Def >For). It is concluded that the competitive level influences the physical demands. SAC registered more accelerations and decelerations, and ENE traveled a greater distance with moderate and intense efforts. There were differences between playing positions; midfielder traveled longer distances and recorded more impacts.

Resumo O monitoramento das demandas físicas durante partidas de futebol com tecnologias GPS fornece informações valiosas que podem ser usadas para aprimorar o desempenho atlético. Portanto, o objetivo deste estudo foi conhecer as demandas físicas dos jogadores de futebol profissional da Costa Rica, bem como analisar a influência da posição de jogo e do nível competitivo durante os jogos. Sessenta jogadores de futebol masculino, 50 da primeira divisão do futebol costarriquenho e 10 da seleção nacional absoluta da CONCACAF (SAC), foram monitorados com um Sistema de Posicionamento Global (GPS) para quantificar variáveis cinemáticas como distância percorrida (m), total já diferentes intensidades (Z 1-5), velocidade máxima (km / h), impactos totais (g), acelerações (m / s) e desacelerações (m / s). As posições de jogo foram categorizadas em: defensores (Def), meio-campistas (Med) e atacantes (Del), e o nível competitivo em: a) SAC, b) Times de elite (ENE) e c) times de nível pré-elite (ENS). Os resultados refletiram diferenças significativas em relação ao nível competitivo na distância percorrida em diferentes intensidades Z1 (SAC> ENS> ENE), Z2 (ENE> SAC> ENS) e Z4 (ENE> SAC> ENS), acelerações (SAC> ENE> ENS) e em desacelerações (SAC> ENS> ENE). Por posições de jogo, as diferenças foram na distância total (Med> Def> Del), na distância percorrida em Z2 (Med> Def> Del) e Z3 (Med> Def> Del), bem como nos impactos totais (Med > Def> Del). Conclui-se que o nível competitivo influencia as demandas físicas. O SAC registrou mais acelerações e desacelerações, e a ENE percorreu uma distância maior com esforços moderados e intensos. Existem diferenças nas posições de jogo, os meio-campistas percorreram distâncias maiores e registraram mais impactos.

Relationship between Skin Temperature Variation and Muscle Damage Markers after a Marathon Performed in a Hot Environmental Condition.

This study aimed to assess the effect of a marathon running at a hot environmental temperature on the baseline skin temperature (Tsk) of the posterior day and to analyze the relationship between Tsk response and muscle damage markers variation. The Tsk, creatine kinase, and lactate dehydrogenase of 16 marathon runners were assessed four times before (15 days and 45 min) and after (24 h and 6 days) a marathon in a hot environment (thermal stress index = 28.3 ± 3.3 °C and humidity ~81%). The Tsk of thirteen different body regions of both right and left lower limbs were analyzed. Higher values after the marathon were observed than 45 min before in creatine kinase (174.3 ± 136.4 UI/L < 1159.7 ± 699.7 UI/L, p < 0.01 and large effect size) and lactate dehydrogenase (362.6 ± 99.9 UI/L < 438 ± 115.5 UI/L, p = 0.02 and moderate effect size). Generally, Tsk was higher the day after the marathon than at the other three moments (e.g., rectus femoris region, 6 days before vs. the day after, 95% confidence interval of the difference (0.3, 1.6 °C), p = 0.04 and large effect size). No relationship or correlation was observed between the variation of Tsk and muscle damage markers (p > 0.05). In conclusion, performing a marathon in a hot environmental condition results in a higher Tsk the day after the marathon. This increase in Tsk could be because of the heat generated by the marathon and its subsequent physiological processes (e.g., increase in endothelial nitric oxide, glycogen resynthesis, or increase of systemic hormones), which would be reflected in the Tsk due to the peripheral vasodilation promoted by the hot environment. However, among these processes, muscle damage does not seem to be of great importance due to the lack of an observed relationship between Tsk and muscle damage markers.

Influence of Altitude and Environmental Temperature on Muscle Functional and Mechanical Activation After 30' Time Trial Run / Influencia de la altitud y la temperatura ambiental en la activación muscular mecánica y funcional posterior a una carrera contrarreloj de 30' / Influência da altitude e da temperatura ambiental na ativação muscular mecânica e funcional depois de uma corrida de velocidade de 30'

Abstract: The purpose of this study was to explore the influence of altitude and environmental temperature on muscle mechanical and functional activation after 30' Time Trial run (30' TT). Twenty physical active males (Age= 20.4 ±3.21 years, VO2max= 47.2 ±5.2 ml/kg/min) performed a 30' TT in three different conditions of altitude and temperature: Control Condition [CC] (1137 m.a.s.l. at 26 ±1.5°C), Heat-Low Condition [HLC] (3 m.a.s.l. at 30.5 ±0.6°C), and Cool-High Condition [CHC] (2369 m.a.s.l. at 14.2 ±0.6°C). Tensiomyography (TMG), Countermovement Jump (CMJ), and Delayed Onset Muscle Soreness (DOMS) were measured pre and post running. During the 30' TT, distance, speed, heart rate (HR), rate of perceived exertion (RPE), and thermal index (WBGT) were measured. Results show a significant decrease in body weight and a significant increase in DOMS and jump height in CMJ after running in each condition. TMG responses increased maximum radial muscle displacement (Dm) and decreased muscle contraction time (Tc) both rectus and biceps femoris muscles after running. During the 30' TT, the results did not show a significant difference in RPE, HR, distance, and speed among conditions. In conclusion, altitude and temperature seem not to significantly affect the mechanical and functional responses 30' TT, despite the tendency of HLC to decrease both activation and performance.

Resumen: El objetivo de este estudio fue determinar si la altitud y la temperatura ambiental influyen en la activación funcional y mecánica, en el nivel muscular, después de 30' de carrera contrarreloj. Veinte hombres físicamente activos (edad = 20,4 ± 3,21 años, VO2máx = 47,2 ± 5,2 ml/kg/min) realizaron 30' de carrera contrarreloj (30'TT) en tres diferentes condiciones de altitud y temperatura: condición control [CC] (1137 msnm, 26 ± 1.5 °C), condición caja y calor [HLC] (3 msnm, 30.5 ± 0.6 °C) y condición de altura y frío [CHC] (2369 msnm, 14.2 ± 0.6 °C). Tensiomiografía (TMG), salto contramovimiento (CMJ) y dolor muscular de aparición tardía (DOMS) se midieron antes y después de la carrera. Durante los 30'TT, se calcularon la distancia, la velocidad, la frecuencia cardíaca (FC), el esfuerzo percibido (RPE) y el índice de estrés térmico (WBGT). Los principales resultados muestran una disminución significativa en el peso corporal y un aumento significativo tanto en el DOMS como en la altura de salto en CMJ, después de correr en cada condición. Las respuestas de TMG aumentaron el desplazamiento muscular radial máximo (Dm) y el tiempo de contracción muscular (Tc), en el recto femoral y en el bíceps femoral, luego de correr. Durante el 30'TT, los resultados no mostraron una diferencia significativa en el RPE, la FC, distancia y velocidad entre las condiciones. En conclusión, la altitud y la temperatura parecen no afectar significativamente las respuestas mecánicas y funcionales después de 30' de carrera contrarreloj, a pesar de la tendencia de la condición HLC de disminuir la activación y el desempeño de la prueba.

Resumo: O objetivo deste estudo foi determinar se a temperatura ambiente e a altitude influenciam a ativação funcional e mecânica a nível muscular após 30' de corrida de velocidade. Vinte homens fisicamente ativos (idade = 20,4 ± 3,21 anos, VO2máx = 47,2 ± 5,2 ml / kg / min) realizaram 30' de corrida de velocidade (30´TT) em três condições diferentes de altitude e temperatura: Condição de controle [CC] (1137 msnm, 26 ± 1,5 ° C, Condição do corpo e calor [HLC] (3 msnm, 30,5 ± 0,6 ° C) e condição de altura e frio [CHC] (2369 msnm, 14,2 ± 0,6). Os valores de Tensiomiografia (TMG), salto de contra movimento (CMJ) e dor muscular de início tardio (DOMS) foram medidos antes e depois da corrida. Durante 30' TT, a distância, a velocidade e a frequência foram medidas, como também a frequência cardíaca (FC), o esforço percebido (RPE) e o índice de cansaço térmico (WBGT). Os principais resultados mostram uma diminuição significativa no peso corporal e um aumento significativo no DOMS e na altura do salto na CMJ, após a corrida em cada condição. As respostas da TMG aumentaram o deslocamento muscular radial máximo (Dm) e o tempo do músculo contraído (Tc) no reto femoral e bíceps femoral, após a corrida. Durante o 30'TT, os resultados não mostraram diferença significativa na RPE, na FC, na distância e na velocidade entre as condições. Em conclusão, altitude e temperatura parecem não afetar significativamente as respostas mecânicas e funcionais após 30 minutos de corrida de velocidade, apesar da tendência da condição HLC de diminuir a ativação e o desempenho do teste.

Speed and heart rate variation during marathon running in a hot environment / Variación de la velocidad y la frecuencia cardiaca durante un maratón en un ambiente caluroso

Abstract The purpose of the study was to analyze the variation of running speed and heart rate in amateur runners during a marathon in a hot environment. Eighteen runners (weight: 65.2 ± 12.21 kg, height: 168.4 ± 10.6 cm, VO2max: 52.9 ± 7.1 ml/kg/min) took part of a beach-side marathon (42195 m) under a temperature of 27.8 ± 3.52 ºC and at 0-80 m altitude. Pearson's correlation showed a significant linear relationship between the increase in thermal stress index (WGBT) and the speed variation (r= 0.168, p= 0.049). In this respect, the total duration of the race revealed a direct relationship with speed (r= 0.675, p= 0.003) and heart rate (r= 0.631, p= 0.007) variation. Multiple regressions analysis showed that 61.6% of the final race time was explained by the speed variation in the 26 to 30 km course section (r 2 = 0.61; F= 26.17; p< 0.001) and 37% by the heart rate variation in the 31 to 35 km section (r 2 = 0.37; F= 10.38; p< 0.001). In conclusion, an increase in the environmental temperature provoked a decrease in running pacing, with a stronger effect in the second half of the race. Therefore, coaches should take these aspects into account in training and strategies to mitigate the impact of these conditions on the physical and physiological performance of amateur runners.

Resumo O presente estudo teve como objetivo analisar a variação da velocidade da corrida e a frequência cardíaca em corredores amadores durante uma maratona em um ambiente de alto índice térmico. Dezoito corredores amadores (peso: 65,2 ± 12,21 kg, altura: 168,4 ± 10,6 cm, VO2max: 52,9 ± 7,1 ml/kg/min) correram uma maratona (42195 m) em proximidade ao mar, sob um índice térmico de 27,8 ± 3,52 ºC e com percurso de 0-80 metros acima do nível do mar. O teste de Pearson apresentou uma correlação significativa entre o aumento do índice de estresse térmico (IBUTG) e a variação da velocidade (r= 0,168, p= 0,049). Neste sentido, a duração total da corrida apresentou uma relação direta com a velocidade (r= 0,675, p= 0,003) e a variação da frequência cardíaca (r= 0,631, p= 0,007). O tempo final da corrida se interpretou em 61,6% e 37% pela variação da velocidade de 26 a 30 km (r 2 = 0,61; F= 26,17; p< 0,001) e pela variabilidade da frequência cardíaca no lapso de 31 a 35 km (r 2 = 0,37; F= 10,38; p< 0,001), respectivamente. Em suma, o índice térmico provoca uma diminuição no ritmo da velocidade, sendo esse efeito maior na segunda metade da corrida. Devido a isso, os preparadores devem planejar treinamentos e estratégias para mitigar o impacto dessas condições no desempenho físico e fisiológico dos corredores amadores.

Resumen El objetivo del presente estudio fue analizar la variación de la velocidad de carrera y la frecuencia cardíaca en corredores aficionados durante un maratón en un entorno de alto índice térmico. Dieciocho corredores aficionados (peso: 65.2 ± 12.21 kg, altura: 168.4 ± 10.6 cm, VO2max: 52.9 ± 7.1 ml/kg/min) corrieron un maratón (42 195 m) en cercanía al mar bajo un índice térmico de 27.8 ± 3.52ºC y con recorrido de 0-80 m.s.n.m. La prueba de Pearson mostró una correlación significativa entre el aumento del índice de estrés termal (TGBH) y la variación de la velocidad (r = 0.168, p = 0.049). En este sentido, la duración total de la carrera presentó una relación directa con la velocidad (r = 0.675, p = 0.003) y la variación de la frecuencia cardíaca (r= 0.631, p = 0.007). El tiempo final de carrera se explicó en un 61.6% y 37% por la variación de la velocidad de 26 a 30 km (r 2 = 0.61; F = 26.17; p < 0.001) y por la variabilidad de la frecuencia cardíaca en el lapso de 31 a 35 km (r 2 = 0.37; F= 10.38; p < 0.001) respectivamente. En conclusión, el índice térmico provoca una disminución en el ritmo de la velocidad, este efecto mayor en la segunda mitad de la carrera. Por lo anterior, entrenadores deben planificar entrenamientos y estrategias para mitigar el impacto de estas condiciones en el desempeño físico y fisiológico de los corredores amateur.

Intermittent Pneumatic Compression and Cold Water Immersion Effects on Physiological and Perceptual Recovery during Multi-Sports International Championship.

BACKGROUND: Congested-fixture championships are common during the selection of the athletes and teams participating in the Olympic Games. Throughout these tournaments, it is fundamental to perform optimally, rest well, and recover between competitions. This study aimed to (a) explore the effectiveness of the use of intermittent pneumatic compression (IPC) and cold water immersion (CWI) to recover muscle mechanical function (MuscleMechFx), hydration status (HydS), pain perception (PainPercep), rate of perceived exertion (RPE), sleep hours, and sleep quality (SleepQual) during a regional multi-sports international championship and (b) compare these results by sex. METHODS: A total of 52 basketball and handball players were exposed to a recovery protocol after the competition as follows: IPC, sequential 20 min at 200 mmHg, and CWI, continuous 12 min at 12 °C. RESULTS: MuscleMechFx presented differences by match and sex (p = 0.058) in time of contraction of biceps femoris; SleepQual and sleep hours were different between matches (<0.01). CONCLUSIONS: IPC + CWI seems to be effective to maintain some MuscleMechFx, HydS, and recovery and pain perception during a congested multi-sport tournament.

Biochemical and Muscle Mechanical Postmarathon Changes in Hot and Humid Conditions.

Gutiérrez-Vargas, R, Martín-Rodríguez, S, Sánchez-Ureña, B, Rodríguez-Montero, A, Salas-Cabrera, J, Gutiérrez-Vargas, JC, Simunic, B, and Rojas-Valverde, D. Biochemical and muscle mechanical postmarathon changes in hot and humid conditions. J Strength Cond Res 34(3): 847-856, 2020-The aim of this study was to compare biochemical changes and mechanical changes in the lower-limb muscles before and after a marathon race in hot and humid conditions. Eighteen healthy runners participated in a marathon at between 28 and 34° C and 81% humidity in Costa Rica. Serum magnesium (Mg), creatine phosphokinase (CPK), lactate dehydrogenase, and hematocrit (HCT) were measured before and after the marathon. Tensiomyography measurements from the rectus femoris (RF) and vastus medialis, muscle displacement (Dm), contraction time (Tc), and velocities of contraction to 10 and 90% of Dm (V10 and V90) were obtained before and after the marathon. Postrace measurements showed a 544% increase in CPK (t(17): -6.925, p < 0.01), a 16% increase in HCT (t(17): -7.466, p < 0.01), a 29% decrease in Mg (t(17): 3.91, p = 0.001), a 2% decrease in body mass (t(17): 4.162, p = 0.001), a 4% increase in Tc of the RF (t(17): -2.588, p = 0.019), and a 12% increase in Dm of the RF (t(17): -2.131, p < 0.048) compared with prerace measurements. No significant biochemical or mechanical differences were found between runners in terms of their finish times. These findings showed that completing a marathon in hot and humid conditions induced a significant reduction in lower-limb muscle stiffness, body mass, and Mg, and increased neuromuscular fatigue, CPK, and HCT, because of muscle damage and dehydration. Knowledge of the effects of heat and humidity may be of value for coaches and sports medicine practitioners in developing effective hydration and recovery protocols for marathon runners in these special conditions.

From big data mining to technical sport reports: the case of inertial measurement units.

The inertial measurement units (IMU) are instruments used to quantify the external load of athletes; they are increasingly common in assessing team and individual sports. This type of instruments has several sensors, such as accelerometers, gyroscopes and magnetometers; this allows access to a large amount of information and analysis possibilities. Due to the complexity of synthesising this data, it is necessary to create a flow for collecting, analysing and presenting the collected data in a simple way and present it as quickly as possible to the technical staff. This report aims to present new methods of reduction of the data and propose a new approach method for the analysis of the IMU's outcomes.

External Workload Indicators of Muscle and Kidney Mechanical Injury in Endurance Trail Running.

Muscle and kidney injury in endurance athletes is worrying for health, and its relationship with physical external workload (eWL) needs to be explored. This study aimed to analyze which eWL indexes have more influence on muscle and kidney injury biomarkers. 20 well-trained trail runners (age = 38.95 ± 9.99 years) ran ~35.27 km (thermal-index = 23.2 ± 1.8 °C, cumulative-ascend = 1815 m) wearing inertial measurement units (IMU) in six different spots (malleolus peroneus [MPleft/MPright], vastus lateralis [VLleft/VLright], lumbar [L1-L3], thoracic [T2-T4]) for eWL measuring using a special suit. Muscle and kidney injury serum biomarkers (creatin-kinase [sCK], creatinine (sCr), ureic-nitrogen (sBUN), albumin [sALB]) were assessed pre-, -post0h and post24h. A principal component (PC) analysis was performed in each IMU spot to extract the main variables that could explain eWL variance. After extraction, PC factors were inputted in multiple regression analysis to explain biomarkers delta change percentage (Δ%). sCK, sCr, sBUN, sALB presented large differences (p < 0.05) between measurements (pre < post24h < post0h). PC's explained 77.5-86.5% of total eWL variance. sCK Δ% was predicted in 40 to 47% by L1-L3 and MPleft; sCr Δ% in 27% to 45% by L1-L3 and MPleft; and sBUN Δ% in 38%-40% by MPright and MPleft. These findings could lead to a better comprehension of how eWL (impacts, player load and approximated entropy) could predict acute kidney and muscle injury. These findings support the new hypothesis of mechanical kidney injury during trail running based on L1-L3 external workload data.

Manganese exposure and working memory-related brain activity in smallholder farmworkers in Costa Rica: Results from a pilot study.

Main sources of manganese (Mn) in the general population are diet and drinking water. Mn is also found in ethylene bisdithiocarbamate (EBDC) fungicides used in agriculture or emitted into the air by ferromanganese plants and welding fumes, which can be additional environmental and occupational sources of exposure. High occupational Mn exposure has been linked with motor, behavioral, and cognitive impairment, but its effects on neural function remain poorly understood. We conducted a functional neuroimaging study in a sample of 48 farmworkers in Zarcero County, Costa Rica, an agricultural region where EBDC fungicides are sprayed. We measured Mn concentrations in farmworkers' toenails (n = 40 farmworkers) and hair (n = 33 farmworkers), and recorded brain activity in the dorsolateral prefrontal cortex during a letter-retrieval working memory task using functional near-infrared spectroscopy (fNIRS). We estimated exposure-outcome associations using multivariable linear regression models adjusted for age and education level. Geometric mean (geometric standard deviation) toenail and hair Mn concentrations were 0.40 µg/g (3.52) and 0.24 µg/g (3.54), respectively. We did not find strong evidence that Mn concentrations were associated with working memory-related brain activity in this sample of farmworkers; we also found null associations between working memory task accuracy and brain activity. However, our small sample size may have limited our ability to detect small effect sizes with statistical precision. Our study demonstrates that fNIRS can be a useful and feasible tool in environmental epidemiology for examining the effects of toxicants, like Mn, on neural function. This may prove to be important for elucidating neuropathological pathways that underlie previously reported associations of elevated Mn exposure with neurotoxic effects.

Exposure to Pesticides and Health Effects on Farm Owners and Workers From Conventional and Organic Agricultural Farms in Costa Rica: Protocol for a Cross-Sectional Study.

BACKGROUND: Pesticide use is increasing in low- and middle-income countries (LMICs) including Costa Rica. This increase poses health risks to farm owners, farm workers, and communities living near agricultural farms. OBJECTIVE: We aimed to examine the health effects associated with occupational pesticide exposure in farm owners and workers from conventional and organic smallholder farms in Costa Rica. METHODS: We conducted a cross-sectional study involving 300 owners and workers from organic and conventional horticultural smallholder farms in Zarcero County, Costa Rica. During the baseline study visit, we administered a structured, tablet-based questionnaire to collect data on sociodemographic characteristics, pesticide exposure, and health conditions (eg, respiratory and allergic outcomes and acute pesticide intoxication symptoms) and administered a neurobehavioral test battery (eg, Finger Tapping Test and Purdue Pegboard); we measured blood pressure, anthropometry (height, weight, and waist circumference), and erythrocytic acetylcholinesterase activity and also collected urine samples. In addition, a functional neuroimaging assessment using near-infrared spectroscopy was conducted with a subset of 50 study participants. During the follow-up study visit (~2-4 weeks after the baseline), we administered participants a short questionnaire on recent pesticide exposure and farming practices and collected hair, toenail, and urine samples. Urine samples will be analyzed for various pesticide metabolites, whereas toenails and hair will be analyzed for manganese (Mn), a biomarker of exposure to Mn-containing fungicides. Self-reported pesticide exposure data will be used to develop exposure intensity scores using an exposure algorithm. Furthermore, exposure-outcome associations will be examined using linear and logistic mixed-effects regression models. RESULTS: Fieldwork for our study was conducted between May 2016 and August 2016. In total, 113 farm owners and 187 workers from 9 organic and 83 conventional horticultural smallholder farms were enrolled. Data analyses are ongoing and expected to be published between 2019 and 2020. CONCLUSIONS: This study is one of the first to examine differences in health effects due to pesticide exposure between farm owners and workers from organic and conventional smallholder farms in an LMIC. We expect that this study will provide critical data on farming practices, exposure pathways, and how occupational exposure to pesticides may affect farm owners and workers' health. Finally, we hope that this study will allow us to identify strategies to reduce pesticide exposure in farm owners and workers and will potentially lay the groundwork for a future longitudinal study of health outcomes in farm owners and workers exposed to pesticides. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/10914.