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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 left 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 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.

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. 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. 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.

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.

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.

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. Resumen 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. Resumo 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.

El uso de la ecografía terapéutica (TUS) en la ciencia del deporte, la medicina y la rehabilitación ha aumentado significativamente en la última década. Este crecimiento ha estado acompañado de un gran interés científico por el estudio de las respuestas durante el tratamiento de lesiones y el hallazgo de la dosis óptima. Por lo tanto, el propósito de esta revisión narrativa fue explorar el conocimiento informado hasta la fecha sobre el uso de TUS y las consideraciones metodológicas al aplicarlo en la evaluación de lesiones deportivas. Se realizó una búsqueda electrónica (PubMed [MEDLINE], Science Direct [EMBASE], Web of Science [WoS] y Google Scholar) siguiendo las pautas de revisión sistemática (PRISMA), e incluyó solo revisiones sistemáticas sobre la aplicación de TUS en los deportes. El resultado de esta revisión es la presentación de algunas consideraciones metodológicas al utilizar la TUS en la práctica deportiva, dando una orientación general para su uso de seguridad, eficiencia y efectividad considerando la necesidad de recuperarse rápidamente de las lesiones en el deporte.

BackgroundPrevious 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.MethodsWe 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.ResultsWe 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 (β=-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 (β=-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.ConclusionOur 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.

The extensive use of wearable sensors in sport medicine, exercise medicine, and health has increased the interest in their study. That is why it is necessary to test these technologies’ efficiency, effectiveness, agreement, and reliability in different settings. Consequently, the purpose of this article was to analyze the magnetic, angular rate, and gravity (MARG) sensor’s test-retest agreement and reliability when assessing multiple body segments’ external loads during off-road running. A total of 18 off-road runners (38.78 ± 10.38 years, 73.24 ± 12.6 kg, 172.17 ± 9.48 cm) ran two laps (1st and 2nd Lap) of a 12 km circuit wearing six MARG sensors. The sensors were attached to six different body segments: left (MPLeft) and right (MPRight) malleolus peroneus, left (VLLeft) and right (VLRight) vastus lateralis, lumbar (L1-L3), and thorax (T2-T4) using a special neoprene suit. After a principal component analysis (PCA) was performed, the total data set variance of all body segments was represented by 44.08%–70.64% for the 1st PCA factor considering two variables, Player LoadRT and Impacts, on L1-L3, respectively. These two variables were chosen among three total accelerometry-based external load indicators (ABELIs) to perform the agreement and reliability tests due to their relevance based on PCAs for each body segment. There were no significant differences between laps in the Player LoadRT or Impacts ( p > 0.05, trivial). The intraclass correlation and lineal correlation showed a substantial to almost perfect over-time test consistency assessed via reliability in both Player LoadRT and Impacts. Bias and t-test assessments showed good agreement between Laps. It can be concluded that MARGs sensors offer significant test re-test reliability and good agreement when assessing off-road kinematics in the six different body segments.

New technological advances are constantly being developed to assess fatigue and muscle damage in sports. Tensiomyography (TMG) has been used as an alternative method to indirectly assess these physiological responses. The aim of this study was to explore the potential use of TMG parameters (muscle radial deformation [Dm], time of contraction [Tc], delay time [Td], deformation rate until 10% [V10] and 90% [V90]) to detect neuromuscular acute fatigue-related responses during a duathlon compared to well-known biochemical (blood lactate [BLa]), perceptual (rate of perceived exertion [RPE]), and functional (jump performance [CMJ]) variables. Twenty-three well-trained athletes (age 33.6 ± 7.2 years, weight 64.4± 9.2 kg, height 1.7 ± 0.2 m, VO2max 56.7± 6.9 mL/kg/min, body fat 16.6 ± 8.4%, lean mass 53.2 ± 11.6 kg) performed a 5k-25k-5k duathlon under controlled indoor conditions at 23°C. TMG muscle properties (left and right gastrocnemius lateralis), BLa, RPE, and CMJ were measured pre-duathlon, during transition 1 (T1), during transition 2 (T2), and post-duathlon. After one-way analyses of variance, there were large differences in BLa ( p10, and V90 as TMG muscle mechanical markers. Compared to well-known fatigue variables (CMJ, RPE, and BLa), Tc and Dm as TMG parameters measured in gastrocnemius lateralis seem to be sensitive enough to detect acute fatigue-related changes during duathlon. Differences reported in Td, V10, and V90 could be the result of muscle post-activation potentiation (PAP) after T1, and more evidence is needed for understanding this PAP phenomenon using TMG.

Gutierrez-Vargas, R, Martin-Rodriguez, S, Sanchez-Urena, B, Rodriguez-Montero, A, Salas-Cabrera, J, Gutierrez-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.

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.

Background/Aim: Chronic kidney disease of unknown etiology (CKDu) affects populations along the Pacific coast of Mesoamerica including the Guanacaste province of Costa Rica. Although the etiology o...

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 &deg, 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 (&lt, 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.

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 (

Soccer is a very popular sport, which has been widely investigated. However, little is known about the effects of congested fixture periods on muscle mechanical responses since access to elite teams during competitive periods is highly restricted. Thus, the goal of this study was to describe the effects of a short-congested fixture period on the neuromechanical parameters related to fatigue and stiffness of elite young soccer players. Nineteen young elite male soccer players (age 17.13 ± 0.51 years, body mass 69.00 ± 1.22 kg, and height 174.09 ± 0.84 cm) participated in the study. The players took part in a preparatory tournament for the FIFA® U-17 World Cup, composed of a total of six matches in 1 week. Pre- and post-tensiomyographic changes were assessed by means of the normalized response speed (Vrn) and other tensiomyographic markers related to muscle fatigue (i.e. maximum radial muscle displacement (Dm) and velocities of contraction at 10% and 90% (V10 and V90) of both legs in two muscles (biceps femoris and rectus femoris). The players presented a possible to likely impairment in Dm, V10, and V90 of both legs and muscles, with the exception of the non-dominant biceps femoris. Vrn did not vary in any condition, although it presented a slight tendency to decrease. The data demonstrated impairments in the tensiomyographic markers in both legs and muscles, with the exception of the non-dominant biceps femoris. A short-congested fixture period in young soccer players leads to a decrease in muscle stiffness due to cumulative fatigue and lack of muscle recovery, this despite the efforts made by the medical staff to counteract the fatigue caused by the games. The use of tensiomyographic markers could be advantageous for rapidly monitoring neuromechanical muscle impairments throughout competitive soccer periods.

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.

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 &plusmn, 9.99 years) ran ~35.27 km (thermal-index = 23.2 &plusmn, 1.8 &deg, C, cumulative-ascend = 1815 m) wearing inertial measurement units (IMU) in six different spots (malleolus peroneus [MPleft/MPright], vastus lateralis [VLleft/VLright], lumbar [L1&ndash, L3], thoracic [T2&ndash, 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 (&Delta, %). sCK, sCr, sBUN, sALB presented large differences (p &lt, 0.05) between measurements (pre &lt, post24h &lt, post0h). PC&rsquo, s explained 77.5&ndash, 86.5% of total eWL variance. sCK &Delta, % was predicted in 40 to 47% by L1&ndash, L3 and MPleft, sCr &Delta, % in 27% to 45% by L1&ndash, and sBUN &Delta, % 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&ndash, L3 external workload data.

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.

Background: Exposure to pesticides has been associated with neurobehavioral deficits and structural brain anomalies in animals and humans. We examined the association between pesticide exposure and...

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 REPOR RR1-10.2196/10914

Resumen Introducción. La termografía infrarroja (TI) es un equipo de imagen que capta las radiaciones de calor emitidas por los cuerpos y las recoge en valores de temperatura. En el ámbito deportivo se utiliza para identificar daños en estructuras músculo-esqueléticas a partir de la variación de la temperatura corporal en zonas anatómicas afectadas. Objetivo. Valorar la efectividad de la TI como herramienta para detectar músculos dañados después de correr una maratón. Materiales y métodos. Se evaluaron 17 corredores antes y después de correr una maratón (42.196 km) utilizando un equipo termográfíco. Resultados. Se encontraron diferencias estadísticamente significativas entre la temperatura previa y posterior a correr una maratón. Se presentó una diferencia entre la medición previa y posterior >1°C en el vasto lateral, vasto medial, recto femoral y aductor de la pierna dominante, lo que, basados en parámetros clínicos, representa un daño en estos músculos. Los aumentos de temperatura se mostraron de manera heterogénea entre las zonas anatómicas. Conclusiones. La TI es una herramienta efectiva para detectar zonas musculares dañadas en corredores después de participar en una maratón. Abstract Introduction: Infrared thermography (IT) is an imaging technique that detects heat radiation emitted by an object and collects it to convert it into temperature values. In sports, it is used to identify damage to musculoskeletal structures based on the variation of body temperature in affected anatomical areas. Objective: To assess the effectiveness of IT as a tool to detect damaged muscles after running a marathon. Materials and methods: 17 runners were assessed before and after running a marathon (42.196 km) using thermographic equipment. Results: Statistically significant temperature differences were found before and after running a marathon. There was a difference between previous and posterior measurement >1°C in the vastus lateralis, vastus medialis, rectus femoris and adductor of the dominant leg, which, based on clinical parameters, indicates damage in these muscles. Increases in temperature were heterogeneous among anatomical areas. Conclusions: IT is an effective tool for detecting damaged muscle areas in runners after participating in a marathon.

Cold water immersion (CWI) has become a highly used recovery method in sports sciences, which seeks to minimize fatigue and accelerate recovery processes; however, tensiomyography (TMG) is a new method to analyze the muscle mechanical response as a recovery indicator after CWI protocols, this relative new tool of muscle function assessment, can lead to new information of understand fatigue recovery trough CWI. The objective of the study was to compare the effect of two CWI protocols, on neuromuscular function recovery. Thirty-nine healthy males (21.8 ± 2.8 years, 73.2 ± 8.2 kg, 176.6 ± 5.3 cm and body fat 13.5 ± 3.4%) were included in the study. Participants were grouped into a continuous immersion (12 min at 12 ± 0.4°C) group, intermittent immersion (2 min immersion at 12 ± 0.4°C + 1 min out of water 23 ± 0.5°C) group, and a control group (CG) (12 min sitting in a room at 23 ± 0.5°C). Afterward, the participants performed eight sets of 30 s counter movement jumps (CMJs) repetitions, with a 90 s standing recovery between sets. Muscle contraction time (Tc), delay time (Td), muscle radial displacement (Dm), muscle contraction velocity at 10% of DM (V10), and muscle contraction velocity at 90% of DM (V90) in rectus, biceps femoris, and CMJ were measured. Neither CWI protocol was effective in showing improved recovery at 24 and 48 h after training compared with the CG (p > 0.05), in any TMG indicator of recovery in either muscle biceps or rectus femoris, nor was the CMJ performance (F(6,111) = 0.43, p = 0.85, ωp2 = 0). Neither CWI protocol contributed to recovery of the neuromuscular function indicator.

El propósito de esta investigación fue comparar las demandas cinemáticas en dos tipos de dimensiones de juego en jugadores de fútbol universitario costarricenses. 14 jugadores universitarios de fútbol de Costa Rica jugaron dos juegos en campo reducido (SSG) (2x10min, 3min de descanso): C1 (600m2) y C2 (1200 m2). Se utilizó un Sistema de Posicionamiento Global para medir las variables cinemáticas y fisiológicas en ambas condiciones. Se utilizó un ANOVA mixto; los resultados sugirieron que C1 y C2 fueron estadísticamente diferentes en velocidad (C1 C2). Al analizar la distancia recorrida por la categoría de velocidad; en acciones de carrera baja, moderada y alta intensidad, los resultados sugieren que C2 posee mayores intensidades en comparación con C1. Esta investigación confirma los resultados de estudios previos sobre la efectividad de SSG para simular condiciones de juego real en períodos cortos de tiempo. Conclusiones: El C2 presentó una mayor intensidad en comparación con el juego C1 con menores demandas fisiológicas. Asimismo, el C2 refleja de manera más exacta las condiciones en partidos oficiales de jugadores costarricenses.