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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., 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 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.

The development of algorithms applied to new technologies allows a better understanding of many of the movements in team sports. The purpose of this work was to analyze the validity, precision, and reproducibility of an algorithm to detect angulation of changes of direction (CoDs) while running, of between 45° and 180°, both to the left and the right at different speeds, in a standardized context. For this, five participants performed a total of 200 CoDs at 13 km/h and 128 CoDs at 18 km/h while wearing three inertial sensors. The information obtained from the sensors was contrasted with observation and coding using high-resolution video. Agreement between systems was assessed using Bland–Altman 95% limits of agreement as well as effect size (ES) and % difference between means. Reproducibility was evaluated using the standard error (CV%). The algorithm overestimated the angulation of 90° and 135° to the right (Cohen’s d > 0.91). The algorithm showed high precision when the angulations recorded at 13 km/h and 18 km/h were compared, except at 45° to the left (mean bias = −2.6°; Cohen’s d = −0.57). All angulations showed excellent reproducibility (CV < 5%) except at 45° (CV = 11%), which worsened when the pre-CoD speed was 18 km/h (CV < 16%). The algorithm showed a high degree of validity and reproducibility to detect angles during CoDs.

The purpose of this study was to study the validity and reproducibility of an algorithm capable of combining information from Inertial and Magnetic Measurement Units (IMMUs) to detect changes of direction (COD). Five participants wore three devices at the same time to perform five CODs in three different conditions: angle (45°, 90°, 135° and 180°), direction (left and right), and running speed (13 and 18 km/h). For the testing, the combination of different % of smoothing applied to the signal (20%, 30% and 40%) and minimum intensity peak (PmI) for each event (0.8 G, 0.9 G, and 1.0 G) was applied. The values recorded with the sensors were contrasted with observation and coding from video. At 13 km/h, the combination of 30% smoothing and 0.9 G PmI was the one that showed the most accurate values (IMMU1: Cohen’s d (d) = −0.29;%Diff = −4%; IMMU2: d = 0.04 %Diff = 0%, IMMU3: d = −0.27, %Diff = 13%). At 18 km/h, the 40% and 0.9 G combination was the most accurate (IMMU1: d = −0.28; %Diff = −4%; IMMU2 = d = −0.16; %Diff = −1%; IMMU3 = d = −0.26; %Diff = −2%). The results suggest the need to apply specific filters to the algorithm based on speed, in order to accurately detect COD.

The contextual factors related to training tasks can play an important role in how a player performs and, subsequently, in how a player trains to face a competition. To date, there has been no study that has investigated the most demanding exercise in different training tasks in female futsal. Therefore, this study aimed to determine the most demanding efforts during different training tasks in a cohort study conducted in professional biological women futsal players using principal component analysis (PCA). A total of 14 elite women futsal players (age = 24.34 ± 4.51 years; height = 1.65 ± 0.60 m; body mass = 63.20 ± 5.65 kg) participated in this study. Seventy training sessions of an elite professional women’s team were registered over five months (pre-season and in-season). Different types of exercises were grouped into six clusters: preventive exercises; analytical situations; exercises in midcourt; exercises in ¾ of the court; exercises in full court; superiorities/inferiorities. Each exercise cluster was composed of 5–7 principal components (PCs), considering from 1 to 5 main variables forming each, explaining from 65 to 75% of the physical total variance. A total of 13–19 sub-variables explained the players’ efforts in each training task group. The first PCs to explain the total variance of training load were as follows: preventive exercises (accelerations; ~31%); analytical situations (impacts; ~23%); exercises in midcourt (high-intensity efforts; ~28%); exercises in ¾ of the court (~27%) and superiorities/inferiorities (~26%) (aerobic/anaerobic components); exercises in full court (anaerobic efforts; ~24%). The PCs extracted from each exercise cluster provide evidence that may assist researchers and coaches during training load monitoring. The descriptive values of the training load support a scientific base to assist coaches in the planning of training schedules.

The objective of the study was to assess the impact of the sampling frequency on the outcomes of collective tactical variables during an official women’s soccer match. To do this, the first half (lasting 46 min) of an official league match of a semi-professional soccer team belonging to the Women’s Second Division of Spain (Reto Iberdrola) was analysed. The collective variables recorded were classified into three main groups: point-related variable (i.e., change in geometrical centre position (cGCp)), distance-related variables (i.e., width, length, height, distance from the goalkeeper to the near defender and mean distance between players), and area-related variables (i.e., surface area). Each variable was measured using eight different sampling frequencies: data every 100 (10 Hz), 200 (5 Hz), 250 (4 Hz), 400 (2.5 Hz), 500 (2 Hz), 1000 (1 Hz), 2000 (0.5 Hz), and 4000 ms (0.25 Hz). With the exception of cGCp, the outcomes of the collective tactical variables did not vary depending on the sampling frequency used (p > 0.05; Effect Size < 0.001). The results suggest that a sampling frequency of 0.5 Hz would be sufficient to measure the collective tactical variables that assess distance and area during an official soccer match.

The contextual factors related to training tasks can play an important role in how a player performs and, subsequently, in how a player trains to face a competition. To date, there has been no study that has investigated the most demanding exercise in different training tasks in female futsal. Therefore, this study aimed to determine the most demanding efforts during different training tasks in a cohort study conducted in professional biological women futsal players using principal component analysis (PCA). A total of 14 elite women futsal players (age = 24.34 ± 4.51 years; height = 1.65 ± 0.60 m; body mass = 63.20 ± 5.65 kg) participated in this study. Seventy training sessions of an elite professional women’s team were registered over five months (pre-season and in-season). Different types of exercises were grouped into six clusters: preventive exercises; analytical situations; exercises in midcourt; exercises in ¾ of the court; exercises in full court; superiorities/inferiorities. Each exercise cluster was composed of 5–7 principal components (PCs), considering from 1 to 5 main variables forming each, explaining from 65 to 75% of the physical total variance. A total of 13–19 sub-variables explained the players’ efforts in each training task group. The first PCs to explain the total variance of training load were as follows: preventive exercises (accelerations; ~31%); analytical situations (impacts; ~23%); exercises in midcourt (high-intensity efforts; ~28%); exercises in ¾ of the court (~27%) and superiorities/inferiorities (~26%) (aerobic/anaerobic components); exercises in full court (anaerobic efforts; ~24%). The PCs extracted from each exercise cluster provide evidence that may assist researchers and coaches during training load monitoring. The descriptive values of the training load support a scientific base to assist coaches in the planning of training schedules.

In Spain, students pursuing a career in athletic training, physical education, or scientific evaluation of sports enroll in a bachelor’s degree in sports sciences. This degree provides knowledge and skills in a broad array of sports settings and promotes research-based interdisciplinary knowledge. However, the student’s syllabus rarely includes specific academic training on anti-doping regulations or doping prevention. The purpose of this study was to assess the anti-doping knowledge of the students undertaking a bachelor’s degree in sports sciences in Spanish universities. One thousand two hundred and thirty-three bachelor students in sport science (907 males, 322 females, and 4 participants with non-binary sex) from 26 Spanish universities completed a validated questionnaire about general anti-doping knowledge. The questionnaire is an adapted version of the Play True Quiz of the World Anti-Doping Agency and contains 37 multiple-choice questions. The score obtained in the questionnaire was transformed into a 0–100-point scale. The questionnaire was distributed among students within each university by a faculty member and it was filled out online. Students obtained a score of 65.8 ± 10.10 points (range = 32–92 points). There was an effect of the course in the score obtained (p < 0.001). Students of the first course (63.6 ± 9.5 points) had lower scores than the remaining courses (p < 0.037) while the students of the fourth course obtained the highest scores (68.7 ± 9.5 points; p < 0.019). The students with an itinerary on sports performance were the respondents with the highest anti-doping knowledge (67.2 ± 10.2) points, followed by the students with an itinerary on health (66.7 ± 9.5 points). The knowledge of basic anti-doping rules and doping prevention strategies of the bachelor students in sports sciences in Spain was suboptimal. Increasing doping prevention information in the syllabus of the bachelor’s degree in sports sciences is essential as these future profe

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., Esteestudo 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 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.

This study aimed to compare physical and physiological demands in youth basketball players according to gender, playing positions, and match outcomes. 64 players (32 female and 32 male) from eight youth sub-elite basketball teams were monitored using an Ultra-Wide Band system and inertial measurement unit in three consecutive matches. The results showed some significant differences, although with magnitudes qualified as small. When the teams won, the guards covered a greater distance at 0-6 km/h than when they lost. When teams lost, the centers covered more distance at 12-18 km/h and 18-21 km/h. The winning female teams presented a lower maximal heart rate (HRmax) compared to the losing teams. The forwards of the winning teams performed greater efforts at 70-80% HRmax, while the forwards of losing teams performed more efforts at 90-95% HRmax. The greatest number of accelerations and decelerations were performed by the female guards and the male forwards. The number of jumps was higher in the male guards and forwards than in the female ones. HRmax was higher in the forwards of the female teams. Efforts at 80%-90% HRmax were higher in male centers. When the female teams won, they had a lower HRmax than when they lost. When efforts exceed 90% of HRmax the teams lost. In conclusion, despite the differences found, the effect of these contextual variables on physical and physiological demands is unclear. Nevertheless, knowing the game's requirements can help the design of training that enhances the performance of youth basketball players., El objetivo de este estudio fue comparar las demandas físicas y fisiológicas en jóvenes jugadores de baloncesto según sexo, posiciones de juego y el resultado de partido. 64 jugadores (32 mujeres y 32 hombres), de ocho equipos juveniles de baloncesto sub-élite, fueron monitoreados utilizando un sistema de Ultra Banda-Ancha y unidades de medición inercial en tres juegos consecutivos. Los resultados evidenciaron algunas diferencias significativas, aunque con magnitudes calificadas como pequeñas. Cuando los equipos ganaban, los bases recorrieron mayor distancia a 0-6 km/h en comparación a cuando perdían. Cuando se perdía, los pivots recorrieron más distancia a 12-18 y 18-21 km/h. Las jugadoras de los equipos ganadores alcanzaron una frecuencia cardiaca máxima (FCmáx) más baja respecto a los equipos perdedores. Los aleros de los equipos ganadores realizaron más esfuerzos a 70-80% FCmáx, mientras que, en los equipos perdedores, los bases realizaron más esfuerzos a 90-95% FCmáx. La mayor cantidad de aceleraciones y desaceleraciones fueron realizada por las bases femeninas y los aleros masculinos. El número de saltos fue mayor en los distribuidores y aleros masculinos que en los femeninos. La FCmáx fue más alta en los aleros de los equipos femeninos. Los esfuerzos a 80%-90% FCmáx fueron mayores en los pivots masculinos. Cuando los equipos femeninos ganaban, presentaban una FCmáx menor que cuando perdían. Los esfuerzos ≥90% FCmáx fueron superiores en mujeres que hombres cuando sus equipos perdían. En conclusión, a pesar de las diferencias encontradas, no queda claro el efecto de estas variables contextuales sobre las demandas físicas y fisiológicas. No obstante, conocer estas exigencias del juego pueden ayudar al diseño de entrenamientos que potencialicen el rendimiento de jugadores jóvenes de baloncesto.

The quantification of training load has become mandatory for coaches and team staff. Within the analyzed variables, distance covered at different speed zones is one of the most studied. However, there is no consensus in the definition of speed zones in the published articles about each team sport, so it makes difficult a comparison between them. Therefore, the purposes of this article were to establish a criteria standard in the classification of speed zones in team sports and to analyze its practical application in basketball. Five speed categories were established for basketball following the methodology described above: 0-10km/h, >10-13.8 km/h, >13.8-17.6 km/h, >17.6-21.5 km/h, and >21.5 km/h. The results showed differences between periods in high-speed displacements and sprints, maximum speed, total decelerations, and accelerations. In conclusion, the categorization of workload based on standard deviation according to maximum speed could be a viable option to individualize the analysis of distance covered per speeds in team sports such as basketball. Its use may lead to a better understanding and contextualization of the locomotion data in specific sports and teams., A quantificação da carga de treinamento se tornou uma obrigação para treinadores e pessoal técnico em esportes coletivos. Entre as variáveis analisadas, a distância percorrida em diferentes zonas de velocidade é uma das mais estudadas. Entretanto, não há consenso na definição de zonas de velocidade nos artigos publicados sobre cada esporte coletivo, o que torna difícil a comparação entre eles. Portanto, os objetivos deste artigo eram estabelecer um critério padrão na classificação das zonas de velocidade nos esportes coletivos e analisar sua aplicação prática no basquetebol. Foram estabelecidas cinco categorias de velocidade para o basquetebol seguindo a metodologia descrita acima: 0-10 km/h, >10-13,8 km/h, >13,8-17,6 km/h, >17,6-21,5 km/h, >21,5 km/h. Os resultados mostram entre períodos de alta velocidade e sprints, velocidade máxima, desacelerações e acelerações totais. Em conclusão, a categorização das demandas com base no desvio padrão de acordo com a velocidade máxima poderia ser uma opção viável para individualizar a análise da distância percorrida pelas velocidades em esportes coletivos como o basquetebol. Seu uso pode ajudar a compreender e contextualizar melhor os dados de movimento em esportes e equipes específicas., La cuantificación de la carga de entrenamiento se ha convertido en una obligación para el personal entrenador y el personal técnico en los deportes de equipo. Dentro de las variables analizadas, la distancia recorrida en distintas zonas de velocidad es una de las más estudiadas. Sin embargo, no existe consenso en la definición de zonas de velocidad en los artículos publicados sobre cada uno de estos deportes, por lo que dificulta la comparación entre ellos. Por tanto, los objetivos de este artículo fueron establecer un criterio estándar en la clasificación de zonas de velocidad en los deportes de equipo y analizar su aplicación práctica en baloncesto. Se establecieron cinco categorías de velocidad para el baloncesto siguiendo la metodología descrita anteriormente: 0-10 km/h, >10-13,8 km/h, >13,8-17,6 km/h, >17,6-21,5 km/h y >21,5 km/h. Los resultados muestran entre períodos en desplazamientos de alta velocidad y esprints, velocidad máxima, desaceleraciones y aceleraciones totales. En conclusión, la categorización de las demandas basadas en la desviación estándar, según la velocidad máxima, podría ser una opción viable para individualizar el análisis de la distancia recorrida por velocidades en deportes de equipo como el baloncesto. Su utilización puede ayudar a una mejor comprensión y contextualización de los datos de desplazamientos en deportes y equipos específicos.

There is currently an increase in inertial flywheel application in strength training; thus, it must be monitored by an accurate and reliable device. The present study tested: (1) the accuracy of an inertial measurement device (IMU) to correctly measure angular velocity and (2) its inter-unit reliability for the measurement of external load. The analysis was performed using Pearson Correlation and Intraclass Correlation Coefficient (ICC). The IMU accuracy was tested using Bland-Altman and the reliability with the coefficient of variation (CV). Ten elite-level football players performed ten series of 5 repetitions in a one-hand standing row exercise (5 series with each arm). A nearly perfect accuracy (ICC=.999) and a very good between-device reliability (Bias=-.010; CV=.017%) was found. IMU is a reliable and valid device to assess angular velocity in inertial flywheel workout objectively., Atualmente, há um aumento na utilização da polia cônica no treinamento de força; portanto, é necessário monitorá-lo com um dispositivo preciso e confiável. O presente estudo testou: (1) a precisão de um dispositivo de medição inercial (IMU), para medir corretamente a velocidade angular e (2) sua confiabilidade interunidades para medição de carga externa. A análise foi realizada por meio da correlação de Pearson e do Coeficiente de Correlação Intraclasse (ICC). A precisão do IMU foi testada usando Bland-Altman e a confiabilidade com o Coeficiente de Variação (CV). Dez jogadores de futebol de elite realizaram 10 séries de 5 repetições em um exercício de linha em pé com uma mão (5 séries com cada braço). Foi encontrado uma precisão quase perfeita (ICC = 0,999) e confiabilidade entre dispositivos muito boa (Bias = - 0,010; CV = 0,017%). IMU's é um dispositivo confiável e válido para avaliar objetivamente a velocidade angular no treinamento inercial da polia cônica., Actualmente, hay un aumento en la utilización de la polea cónica en el entrenamiento de fuerza; por lo tanto, es necesario monitorearlo con un dispositivo preciso y confiable. El presente estudio probó: (1) la precisión de un dispositivo de medición inercial (IMU), para medir correctamente la velocidad angular y (2) su confiabilidad entre unidades para la medición de carga externa. El análisis se realizó utilizando la correlación de Pearson y el Coeficiente de Correlación Intra-clase (CCI). La precisión de la IMU se probó usando Bland-Altman y la confiabilidad con el Coeficiente de Variación (CV). Diez jugadores de fútbol de nivel élite realizaron 10 series de 5 repeticiones en un ejercicio de fila de pie con una mano (5 series con cada brazo). Se encontró una precisión casi perfecta (ICC = .999) y una muy buena confiabilidad entre dispositivos (Sesgo = -. 010; CV = .017%). IMU´s es un dispositivo confiable y válido para evaluar objetivamente la velocidad angular en el entrenamiento inercial de la polea cónica.

In Spain, students pursuing a career in athletic training, physical education, or scientific evaluation of sports enroll in a bachelor’s degree in sports sciences. This degree provides knowledge and skills in a broad array of sports settings and promotes research-based interdisciplinary knowledge. However, the student’s syllabus rarely includes specific academic training on anti-doping regulations or doping prevention. The purpose of this study was to assess the anti-doping knowledge of the students undertaking a bachelor’s degree in sports sciences in Spanish universities. One thousand two hundred and thirty-three bachelor students in sport science (907 males, 322 females, and 4 participants with non-binary sex) from 26 Spanish universities completed a validated questionnaire about general anti-doping knowledge. The questionnaire is an adapted version of the Play True Quiz of the World Anti-Doping Agency and contains 37 multiple-choice questions. The score obtained in the questionnaire was transformed into a 0–100-point scale. The questionnaire was distributed among students within each university by a faculty member and it was filled out online. Students obtained a score of 65.8 ± 10.10 points (range = 32–92 points). There was an effect of the course in the score obtained (p < 0.001). Students of the first course (63.6 ± 9.5 points) had lower scores than the remaining courses (p < 0.037) while the students of the fourth course obtained the highest scores (68.7 ± 9.5 points; p < 0.019). The students with an itinerary on sports performance were the respondents with the highest anti-doping knowledge (67.2 ± 10.2) points, followed by the students with an itinerary on health (66.7 ± 9.5 points). The knowledge of basic anti-doping rules and doping prevention strategies of the bachelor students in sports sciences in Spain was suboptimal. Increasing doping prevention information in the syllabus of the bachelor’s degree in sports sciences is essential as these future profe

In Spain, students pursuing a career in athletic training, physical education, or scientific evaluation of sports enroll in a bachelor’s degree in sports sciences. This degree provides knowledge and skills in a broad array of sports settings and promotes research-based interdisciplinary knowledge. However, the student’s syllabus rarely includes specific academic training on anti-doping regulations or doping prevention. The purpose of this study was to assess the anti-doping knowledge of the students undertaking a bachelor’s degree in sports sciences in Spanish universities. One thousand two hundred and thirty-three bachelor students in sport science (907 males, 322 females, and 4 participants with non-binary sex) from 26 Spanish universities completed a validated questionnaire about general anti-doping knowledge. The questionnaire is an adapted version of the Play True Quiz of the World Anti-Doping Agency and contains 37 multiple-choice questions. The score obtained in the questionnaire was transformed into a 0–100-point scale. The questionnaire was distributed among students within each university by a faculty member and it was filled out online. Students obtained a score of 65.8 ± 10.10 points (range = 32–92 points). There was an effect of the course in the score obtained (p < 0.001). Students of the first course (63.6 ± 9.5 points) had lower scores than the remaining courses (p < 0.037) while the students of the fourth course obtained the highest scores (68.7 ± 9.5 points; p < 0.019). The students with an itinerary on sports performance were the respondents with the highest anti-doping knowledge (67.2 ± 10.2) points, followed by the students with an itinerary on health (66.7 ± 9.5 points). The knowledge of basic anti-doping rules and doping prevention strategies of the bachelor students in sports sciences in Spain was suboptimal. Increasing doping prevention information in the syllabus of the bachelor’s degree in sports sciences is essential as these future profe

The contextual factors related to training tasks can play an important role in how a player performs and, subsequently, in how a player trains to face a competition. To date, there has been no study that has investigated the most demanding exercise in different training tasks in female futsal. Therefore, this study aimed to determine the most demanding efforts during different training tasks in a cohort study conducted in professional biological women futsal players using principal component analysis (PCA). A total of 14 elite women futsal players (age = 24.34 ± 4.51 years; height = 1.65 ± 0.60 m; body mass = 63.20 ± 5.65 kg) participated in this study. Seventy training sessions of an elite professional women’s team were registered over five months (pre-season and in-season). Different types of exercises were grouped into six clusters: preventive exercises; analytical situations; exercises in midcourt; exercises in ¾ of the court; exercises in full court; superiorities/inferiorities. Each exercise cluster was composed of 5–7 principal components (PCs), considering from 1 to 5 main variables forming each, explaining from 65 to 75% of the physical total variance. A total of 13–19 sub-variables explained the players’ efforts in each training task group. The first PCs to explain the total variance of training load were as follows: preventive exercises (accelerations; ~31%); analytical situations (impacts; ~23%); exercises in midcourt (high-intensity efforts; ~28%); exercises in ¾ of the court (~27%) and superiorities/inferiorities (~26%) (aerobic/anaerobic components); exercises in full court (anaerobic efforts; ~24%). The PCs extracted from each exercise cluster provide evidence that may assist researchers and coaches during training load monitoring. The descriptive values of the training load support a scientific base to assist coaches in the planning of training schedules.

The objectives of this study are: (1) to compare match load demands through load indicators between starters and substitutes, and (2) analyze the degree of correlation in the variables analyzed in this investigation. Twenty-two semi-professional soccer players were analyzed during a full season’s 38 official matches. Participants were assigned to two different groups according to their participation in the game: (a) starting-up players (≥90 min played) vs. substitute players (≥45 min played in the second half). Statistical analysis was performed by using Mann–Whitney U test to conduct pairwise comparison and Spearman correlation to demands correlation in each group. Significant differences in both absolute and relative variables in player load (P, p < 0.01; p < 0.01), metabolic power (MP, p < 0.01; p = 0.15), equivalent distance index (EDI, p = 0.87; p < 0.01), dynamic stress load (DSI, p < 0.01; p = 0.977), energy expenditure (EE, p < 0.01; p < 0.01), high metabolic load events (HMLE, p < 0.01; p < 0.01), and high metabolic load distance (HMLD, p < 0.01; p = 0.09). Overall, high direct correlations in the starting-up group in absolute and relative demands of PL, PM, HMLD, EE, and DSL were found, as well as high inverse correlation in the substitute group in all variables, excluding DSL and HMLD. In conclusion, the absolute differences found suggested a different training load management during training sessions.

The objective of the study was to assess the impact of the sampling frequency on the outcomes of collective tactical variables during an official women’s soccer match. To do this, the first half (lasting 46 min) of an official league match of a semi-professional soccer team belonging to the Women’s Second Division of Spain (Reto Iberdrola) was analysed. The collective variables recorded were classified into three main groups: point-related variable (i.e., change in geometrical centre position (cGCp)), distance-related variables (i.e., width, length, height, distance from the goalkeeper to the near defender and mean distance between players), and area-related variables (i.e., surface area). Each variable was measured using eight different sampling frequencies: data every 100 (10 Hz), 200 (5 Hz), 250 (4 Hz), 400 (2.5 Hz), 500 (2 Hz), 1000 (1 Hz), 2000 (0.5 Hz), and 4000 ms (0.25 Hz). With the exception of cGCp, the outcomes of the collective tactical variables did not vary depending on the sampling frequency used (p > 0.05; Effect Size < 0.001). The results suggest that a sampling frequency of 0.5 Hz would be sufficient to measure the collective tactical variables that assess distance and area during an official soccer match.

Since the accelerating development of technology applied to team sports and its subsequent high amount of information available, the need for data mining leads to the use of data reduction techniques such as Principal Component Analysis (PCA). This systematic review aims to identify determinant variables in soccer, basketball and rugby using exploratory factor analysis for, training design, performance analysis and talent identification. Three electronic databases (PubMed, Web of Science, SPORTDiscus) were systematically searched and 34 studies were finally included in the qualitative synthesis. Through PCA, data sets were reduced by 75.07%, and 3.9 ± 2.53 factors were retained that explained 80 ± 0.14% of the total variance. All team sports should be analyzed or trained based on the high level of aerobic capacity combined with adequate levels of power and strength to perform repeated high-intensity actions in a very short time, which differ between team sports. Accelerations and decelerations are mainly significant in soccer, jumps and landings are crucial in basketball, and impacts are primarily identified in rugby. Besides, from these team sports, primary information about different technical/tactical variables was extracted such as (a) soccer: occupied space, ball controls, passes, and shots; (b) basketball: throws, rebounds, and turnovers; or (c) rugby: possession game pace and team formation. Regarding talent identification, both anthropometrics and some physical capacity measures are relevant in soccer and basketball. Although overall, since these variables have been identified in different investigations, further studies should perform PCA on data sets that involve variables from different dimensions (technical, tactical, conditional).

The aim of the review was to identify the spatial tactical variables used to assess the use of space in team sports using positional data. In addition, we examined computational methods, performed a critical assessment and suggested future considerations. We considered four electronic databases. A total of 3973 documents were initially retrieved and only 15 articles suggested original spatial variables or different computation methods. Spatial team sport tactical variables can be classified into 3 principal types: occupied space, total field coverage by several players; exploration space, the mean location (+/- standard deviations in X- and Y-directions) of the player/team during the entire game; and dominant/influence space, the region the players can reach before any other players. Most of the studies, i.e., 55%, did not include goalkeepers (GKs) and total playing space to assess occupied space, however, several proposed new variables that considered that all playing space could be "played" (i.e. effective free-space, normalized surface area). Only a collective exploration space variable has been suggested: the major range of the geometrical centre (GC). This suggestion could be applied to assess collective exploration space variables at a sub-system level. The measurement of the dominant/influence space has been based on the Voronoi region (i.e. distance d criteria), but several studies also based their computation on the time (t). In addition, several weighted dominant areas have been suggested. In conclusion, the use of spatial collective tactical variables considering the principal structural traits of each team sport (e.g. players of both teams, the location of the space with respect to the goal, and the total playing space) is recommended

Ultra-wide band (UWB) based local positioning systems (LPS) are based on devices and a portable antenna set. The optimal installation height of the antennae is crucial to ensure data accuracy. Collective variables are metrics that consider at least two pairs of coordinates, which may lead to lower precision than an individual one. Therefore, the aim of this study was to compare the influence of antenna height with collective metrics using a UWB (i.e., IMU; WIMU PRO™, RealTrack Systems, Almeria, Spain) based LPS. Data acquisition was carried out in a basketball court measuring 28 × 15 m. Five devices were used; one of which was carried by a healthy and well-trained athlete (age: 38 years, mass: 76.34 kg, height 1.70 m), while each of the remaining four was positioned on a tripod in one of the four corners of the court. Four kinds of variables were extracted: (1) static distances, (2) dynamic distances, (3) static areas and (4) dynamic areas in all antenna installation modes of 0.15, 1.30 and 2.00 m. The results showed that the antenna of 1.30 m provided better accuracy for all measures (% difference range from −0.94 to 1.17%) followed by the antenna of 2.00 m (% difference range from −2.50 to 2.15%), with the antenna of 0.15 m providing the worst accuracy level (% difference range from −1.05 to 3.28%). Overall, the measurements of distance metrics showed greater accuracy than area metrics (distance % difference range from −0.85 to 2.81% and area % difference range from −2.50 to 3.28). In conclusion, the height of the antennae in basketball courts should be similar to the height at which the devices are attached to a player’s upper back. However, as the precision is sensitive to the magnitude of the measure, further studies should assess the effects of the relative height of antennae in team sports with greater playing spaces.

Background: Consistent evidence suggests that exercise improves cognition and decision making, with preliminary evidence suggesting that brain-derived neurotrophic factors (BDNFs) may mediate these effects on high-intensity interval activities, such as in football playing. We conducted a systematic review of studies on football players or football task interventions that evaluated the causality of exercise or its relationship with changes in the basal BDNF level. Methods: The search was conducted in PubMed, SPORTDiscus, Cochrane, and FECYT (Web of Sciences, CCC, DIIDW, KJD, MEDLINE, RSCI, and SCIELO) according to the guidelines for performing systematic reviews in the sport sciences field. Results: From the 44 studies initially identified, seven studies were fully reviewed, and their outcome measures were extracted and analysed. In the scientific study of football, the studies published thus far have explored the relationship of serum BDNF levels and other cognitive function factors with the genetic expression of polymorphisms, the anthropometric and fitness conditions, the acute exercise effect of the match, and the typical actions of the match such as heading. Conclusions: The heterogeneity of designs and variables evaluated in studies related to BDNF exercise or interaction and football playing does not allow us to conclusively determine that there is a relationship with the cause or effect of genetic, anthropometric, or conditional factors that derive from an increase in BDNF due to actions during the playing of football.

Background: Consistent evidence suggests that exercise improves cognition and decision making, with preliminary evidence suggesting that brain-derived neurotrophic factors (BDNFs) may mediate these effects on high-intensity interval activities, such as in football playing. We conducted a systematic review of studies on football players or football task interventions that evaluated the causality of exercise or its relationship with changes in the basal BDNF level. Methods: The search was conducted in PubMed, SPORTDiscus, Cochrane, and FECYT (Web of Sciences, CCC, DIIDW, KJD, MEDLINE, RSCI, and SCIELO) according to the guidelines for performing systematic reviews in the sport sciences field. Results: From the 44 studies initially identified, seven studies were fully reviewed, and their outcome measures were extracted and analysed. In the scientific study of football, the studies published thus far have explored the relationship of serum BDNF levels and other cognitive function factors with the genetic expression of polymorphisms, the anthropometric and fitness conditions, the acute exercise effect of the match, and the typical actions of the match such as heading. Conclusions: The heterogeneity of designs and variables evaluated in studies related to BDNF exercise or interaction and football playing does not allow us to conclusively determine that there is a relationship with the cause or effect of genetic, anthropometric, or conditional factors that derive from an increase in BDNF due to actions during the playing of football.

The aim of the review was to identify the spatial tactical variables used to assess the use of space in team sports using positional data. In addition, we examined computational methods, performed a critical assessment and suggested future considerations. We considered four electronic databases. A total of 3973 documents were initially retrieved and only 15 articles suggested original spatial variables or different computation methods. Spatial team sport tactical variables can be classified into 3 principal types: occupied space, total field coverage by several players; exploration space, the mean location (+/- standard deviations in X- and Y-directions) of the player/team during the entire game; and dominant/influence space, the region the players can reach before any other players. Most of the studies, i.e., 55%, did not include goalkeepers (GKs) and total playing space to assess occupied space, however, several proposed new variables that considered that all playing space could be "played" (i.e. effective free-space, normalized surface area). Only a collective exploration space variable has been suggested: the major range of the geometrical centre (GC). This suggestion could be applied to assess collective exploration space variables at a sub-system level. The measurement of the dominant/influence space has been based on the Voronoi region (i.e. distance d criteria), but several studies also based their computation on the time (t). In addition, several weighted dominant areas have been suggested. In conclusion, the use of spatial collective tactical variables considering the principal structural traits of each team sport (e.g. players of both teams, the location of the space with respect to the goal, and the total playing space) is recommended

Ultra-wide band (UWB) based local positioning systems (LPS) are based on devices and a portable antenna set. The optimal installation height of the antennae is crucial to ensure data accuracy. Collective variables are metrics that consider at least two pairs of coordinates, which may lead to lower precision than an individual one. Therefore, the aim of this study was to compare the influence of antenna height with collective metrics using a UWB (i.e., IMU; WIMU PRO™, RealTrack Systems, Almeria, Spain) based LPS. Data acquisition was carried out in a basketball court measuring 28 × 15 m. Five devices were used; one of which was carried by a healthy and well-trained athlete (age: 38 years, mass: 76.34 kg, height 1.70 m), while each of the remaining four was positioned on a tripod in one of the four corners of the court. Four kinds of variables were extracted: (1) static distances, (2) dynamic distances, (3) static areas and (4) dynamic areas in all antenna installation modes of 0.15, 1.30 and 2.00 m. The results showed that the antenna of 1.30 m provided better accuracy for all measures (% difference range from −0.94 to 1.17%) followed by the antenna of 2.00 m (% difference range from −2.50 to 2.15%), with the antenna of 0.15 m providing the worst accuracy level (% difference range from −1.05 to 3.28%). Overall, the measurements of distance metrics showed greater accuracy than area metrics (distance % difference range from −0.85 to 2.81% and area % difference range from −2.50 to 3.28). In conclusion, the height of the antennae in basketball courts should be similar to the height at which the devices are attached to a player’s upper back. However, as the precision is sensitive to the magnitude of the measure, further studies should assess the effects of the relative height of antennae in team sports with greater playing spaces.

Since the accelerating development of technology applied to team sports and its subsequent high amount of information available, the need for data mining leads to the use of data reduction techniques such as Principal Component Analysis (PCA). This systematic review aims to identify determinant variables in soccer, basketball and rugby using exploratory factor analysis for, training design, performance analysis and talent identification. Three electronic databases (PubMed, Web of Science, SPORTDiscus) were systematically searched and 34 studies were finally included in the qualitative synthesis. Through PCA, data sets were reduced by 75.07%, and 3.9 ± 2.53 factors were retained that explained 80 ± 0.14% of the total variance. All team sports should be analyzed or trained based on the high level of aerobic capacity combined with adequate levels of power and strength to perform repeated high-intensity actions in a very short time, which differ between team sports. Accelerations and decelerations are mainly significant in soccer, jumps and landings are crucial in basketball, and impacts are primarily identified in rugby. Besides, from these team sports, primary information about different technical/tactical variables was extracted such as (a) soccer: occupied space, ball controls, passes, and shots; (b) basketball: throws, rebounds, and turnovers; or (c) rugby: possession game pace and team formation. Regarding talent identification, both anthropometrics and some physical capacity measures are relevant in soccer and basketball. Although overall, since these variables have been identified in different investigations, further studies should perform PCA on data sets that involve variables from different dimensions (technical, tactical, conditional).

The purpose of this study was to analyze the external and internal load of Costa Rican handball referees according to sex and game periods. Nine referees (6 men and 3 women) were monitored during U19 handball matches, using an ultra-wide band local positioning system (UWB) and WIMUPro™ inertial units (IMU). The results showed a total distance of 4566.54±494.02 m (46.95% at 0-6 km/h, 32.97% at 6-12 km/h, 18.11% at 12-18 km/h and 1.96% >18 km/h). 1298.34±151.42 m/s2 accelerations and 1297.73±152.09 m/s2 decelerations were performed. Maximal speed was 19.63±1.85 km/h and average speed was 4.80±0.34 km/h. Player LoadRT was 50.53±9.39 UA. Maximal and average heart rate was 170.59±18.20 bpm 143.06±16.94 bpm respectively. 60% of the efforts were <80% of maximum heart rate. Total energy expenditure was 372.34±67.80 kcal. No significant differences were found in physiological variables between sexes, although men covered greater distance at 0-6 km/h. In the second periods the total distance (m/min), distance at 6-12 km/h, 12-18 km/h (m/min) and >18 km/h, average speed, impacts at 3-5g and >5g, Player LoadRT, and energy expenditure decreased. In conclusion, sex does not seem to affect the external or internal load, while the game period influenced on the external load, El propósito de este estudio fue analizar la carga externa e interna de árbitros costarricenses de balonmano según sexo y periodos de juego. Nueve árbitros (6 hombres y 3 mujeres) fueron monitoreados durante partidos de balonmano Sub-19, utilizando un sistema de posicionamiento local de banda ultra ancha (UWB) y unidades inerciales WIMUPro™(IMU). Los resultados mostraron una distancia total de 4566.54±494.02 m (46,95% a 0-6 km/h, 32,97% a 6-12 km/, 18,11% a 12-18 km/h y 1,96% a >18 km/h. Se realizaron 1298.34±151.42 m/s2 aceleraciones y 1297.73±152.09 m/s2 desaceleraciones. La velocidad máxima fue 19.63±1.85 km/h y la velocidad promedio fue 4.80±0.34 km/h. Player LoadRT fue 50.53±9.39 UA. La frecuencia cardíaca máxima y promedio fueron 170.59±18.20 lpm y 143.06±16.94 lpm respectivamente. El 60% de los esfuerzos fueron <80% de la frecuencia cardíaca máxima. El gasto energético total fue 372.34±67.80 kcal. No hubo diferencias significativas en variables fisiológicas entre sexos, aunque los hombres recorrieron mayor distancia a 0-6 km/h. En los segundos periodos la distancia total (m/min), distancia a 6-12 km/h, 12-18 km/h (m/min) y >18 km/h, velocidad media, impactos a 3-5 g y > 5g, Player LoadRT y gasto energético disminuyeron. En conclusión, el sexo no parece afectar la carga externa o interna, mientras que el periodo de juego sí influyó en la carga externa.

An association between accelerometer workload and injury risk has been found previously. However, any research has assessed the absorption dynamics of external workload through the measurement in different anatomical locations simultaneously. A cross-sectional study was designed to: (i) to describe the multi-joint external workload profile of youth soccer players, (ii) to identify between-participant differences related to anatomical locations, (iii) to analyze the workload dynamics at different speeds at joints and body segments, (iv) to characterize the multi-joint individual workload and the within-participant difference in each body segment. Twenty-one U-18 male players, that were part of a Youth Spanish First Division soccer team, performed an incremental running treadmill test and wore four WIMU PROTM inertial devices in lower limb (ankle-knee) and spine (lower-upper back) locations to register cumulative tri-axial accelerometry-based workload (PlayerLoad, PLRT). The main results have shown that the highest PLRT was detected at the lower limb, especially at the ankle. Different dynamics of accelerometer workload have been found between lower and upper limb, being them between ankle-knee at 12-km/h and lower-upper back at 9.5-km/h (p<.05). Between-participants’ differences were shown at all joints, finding the highest differences at the upper back (p<.01; d=2.17). Finally, the body segment knee-lower back reported the highest differences (%diff=34.25-to-67.28; d=2.20-to-4.77). In conclusion, a great between-participants external workload variability was found at joints and body segments, being recommended for an individualized assessment and specific training protocols., Una asociación entre la carga acelerometría y el riesgo de lesión ha sido encontrada previamente. Sin embargo, no existen investigaciones que evalúen la dinámica de absorción de carga externa a través de diferentes ubicaciones anatómicas simultáneamente. Un estudio transversal fue diseñado para: (i) describir el perfil multi-ubicación de carga externa en jugadores jóvenes de fútbol, (ii) identificar diferencias entre sujetos relacionadas con las ubicaciones anatómicas, (iii) analizar la dinámica de carga a diferentes velocidades en diferentes ubicaciones anatómicas y segmentos corporales, (iv) caracterizar el perfil multi-ubicación individual y las diferencias intra-sujeto en cada segmento corporal. 21 jugadores masculinos U-18 que pertenecían a un equipo de fútbol de Primera División Nacional Juvenil realizaron un test incremental en tapiz rodante portando cuatro dispositivos inerciales WIMU PROTM en diferentes ubicaciones del tren inferior (rodilla-tobillo) y columna (espalda alta y baja) para registrar la carga acelerométrica tri-axial acumulada (PlayerLoad, PLRT). Los principales resultados muestran que el mayor PLRT fue detectando en el tren inferior, especialmente en el tobillo. Diferentes dinámicas de carga acelerométrica han sido encontrados entre el tren inferior y el tren superior, siendo estas diferencias entre tobillo-rodilla a 12 km/h y entre espalda alta-baja a 9.5 km/h (p<.05). Diferencias inter-sujeto fueron encontradas en todas las ubicaciones, encontrando las mayores diferencias en la espalda alta (p<.01; d=2.17). Finalmente, el segmento corporal rodilla-espalda baja reportó las mayores diferencias (%diff=34.25-to-67.28; d=2.20-to-4.77). En conclusión, una alta variabilidad inter-sujeto en la carga externa registrada fue encontrada en todas las ubicaciones y segmentos corporales, siendo recomendable su individualización y entrenamiento específico.

The aim of this study was to assess the principal components (PC) of women’s field hockey players´ TL distinguishing by playing positions (i.e., back, midfielder, forward). Data were collected from sixteen players belonging to the Spanish National women’s field hockey team during 13 official matches from the European Championship, World Series, and Pre-Olympic tournament. The Principal Component Analysis (PCA) grouped a total of 16 variables in five to six PC, explaining between 68.6 and 80% of the total variance. Different variables formed the PC that explain the player’s performance in different field positions. There were differences by positions in the distance covered at 21 to 24 km·h-1 (midfielders>forwards), decelerations from 5 to 4 m·s-2 (midfielders>forwards), and in maximum accelerations (midfielders>backs). Overall, strength and conditioning coaches should combine exercises which induce a high degree of aerobic endurance and power. However, some specification should be made by playing position: (1) defenders should perform training sessions with at least the same amount of volume as in the matches; (2) forwards should perform training efforts that ensure high repeated sprint ability; and (3) midfielders should perform a high training volume to develop high-intensity aerobic endurance, in combination with short-term efforts., El objetivo de este estudio fue evaluar los componentes principales (CP) de rendimiento de las jugadoras de hockey hierba en diferentes posiciones del campo (defensiva, mediocampista, delantera). Se registraron datos de 16 jugadoras de la selección española absoluta de hockey hierba femenino durante 13 partidos oficiales del Campeonato de Europa, Serie Mundial y del Torneo Preolímpico. El Análisis de Componentes Principales (ACP) agrupó un total de 16 variables en cinco/seis CP, lo que explica entre el 68,6 y el 80% de la varianza total. Diferentes variables formaron los PC que explican el rendimiento de las jugadoras en diferentes posiciones del campo. Se encontraron diferencias por posiciones en distancia de 21 a 24 km/h (centrocampistas > delanteras), deceleraciones de 5 a 4 m/s (mediocampistas > delanteras) y en aceleraciones máximas (mediocampistas > defensas). En general, los preparadores físicos deben combinar ejercicios que lleven a un alto grado de resistencia aeróbica y potencia, aunque se deben hacer algunas especificaciones por posición de juego: (1) las defensoras deben realizan sesiones de entrenamiento con al menos la misma cantidad de volumen que en el partido; (2) las delanteras deben realizar durante los entrenamientos esfuerzos que aseguren una alta capacidad de repetir carreras de alta intensidad; y (3) las mediocampistas deben desarrollar una resistencia aeróbica de alta intensidad en combinación con esfuerzos cortos e intensos.

Principal Component Analysis (PCA) has not been used to assess the principal component (PC) of players´ external training loads (TL) in futsal. In addition, no previous study has analyzed the PC of players´ external TL depending on the half of the match in futsal. Thus, this study aimed to assess the PC of players´ external TL considering an entire official futsal match distinguishing by halves (1st and 2nd halves). Two teams of twelve amateur futsal players (Spanish 3rd division) participated in the final match of the futsal cup and external TL was quantified using eight antennas ultra-wideband technology. Through PCA statistical analysis, 10 variables formed the 10 PC. Specifically, three PC for the entire match, four for the 1st half, and three for the 2nd half were extracted. Considering the match as a whole, three PC explained the players´ external TL formed by eight variables: distance covered (m/min), distance covered at high speed running (m/min), distance covered at explosive speed (m/min), total accelerations (n/min), total decelerations between 2-1 m/s/s (n/min), distance covered at 24-50 km/h (m/min), total impacts between 8-100g (n/min) and Jumps performed (n/min). The PC variables differed between halves: a) in the 1st half 74.5% was explained by four PC composed of 8 variables in total, and b) in the 2nd half 67.6% was explained by three PC. The results suggest that the use of only one PC could potentially lead to an underestimation of the external TL demands in futsal matches. It seems that a combination of 3-4 PC from a total of 8 to 10 variables are required to explain senior amateur futsal official games. In addition, the match half should be considered to assess the external TL in team sports., El análisis de componentes principales (ACP) no se ha utilizado para conocer los componentes principales (CP) de las cargas de entrenamiento (CE) de los jugadores en fútbol sala. Además, no se han publicado estudios que analicen los CP de la CE de los jugadores en función del período de juego en fútbol sala. Por lo tanto, este estudio tuvo como objetivo evaluar los CP de la CE de los jugadores considerando un partido de fútbol sala oficial diferenciando por períodos. Dos equipos de doce jugadores amateurs de fútbol sala (3a división española) participaron en una final de la copa de fútbol sala. A través del análisis estadístico de CP, 10 variables formaron los 10 CP. Concretamente, se extrajeron 3 CP para el partido en su totalidad, 4 para el primer período y 3 para el segundo período. Considerando el partido como un todo, 3 CP formados por 8 variables explicaron la CE de los jugadores: Distancia cubierta (m / min), carrera a alta velocidad (m / min), distancia recorrida a velocidad explosiva (m / min), número de aceleraciones totales (n / min), número de desaceleraciones de 2 a 1 m/s (n / min), distancia cubierta de 24 a 50 km/h (m / min), impactos 8-100g (n / min) y saltos (n / min). Las variables de los CP diferían entre períodos: a) en el primer período, 4 CP explicaron el 74.5% de la CE de los jugadores, mientras que b) en el segundo período, 3 CP explicaron el 67.6%. Los resultados sugirieron que el uso de un solo CP podría conducir a una subestimación de las demandas de CE en los partidos de fútbol sala. Parece que se requiere una combinación de 3-4 CP formados por un total de 8 variables para explicar los partidos oficiales de fútbol sala amateur. Además, se debe considerar el ACP por períodos para evaluar el CE en los deportes de equipo.

Background: Consistent evidence suggests that exercise improves cognition and decision making, with preliminary evidence suggesting that brain-derived neurotrophic factors (BDNFs) may mediate these effects on high-intensity interval activities, such as in football playing. We conducted a systematic review of studies on football players or football task interventions that evaluated the causality of exercise or its relationship with changes in the basal BDNF level. Methods: The search was conducted in PubMed, SPORTDiscus, Cochrane, and FECYT (Web of Sciences, CCC, DIIDW, KJD, MEDLINE, RSCI, and SCIELO) according to the guidelines for performing systematic reviews in the sport sciences field. Results: From the 44 studies initially identified, seven studies were fully reviewed, and their outcome measures were extracted and analysed. In the scientific study of football, the studies published thus far have explored the relationship of serum BDNF levels and other cognitive function factors with the genetic expression of polymorphisms, the anthropometric and fitness conditions, the acute exercise effect of the match, and the typical actions of the match such as heading. Conclusions: The heterogeneity of designs and variables evaluated in studies related to BDNF exercise or interaction and football playing does not allow us to conclusively determine that there is a relationship with the cause or effect of genetic, anthropometric, or conditional factors that derive from an increase in BDNF due to actions during the playing of football.

The aim of the review was to identify the spatial tactical variables used to assess the use of space in team sports using positional data. In addition, we examined computational methods, performed a critical assessment and suggested future considerations. We considered four electronic databases. A total of 3973 documents were initially retrieved and only 15 articles suggested original spatial variables or different computation methods. Spatial team sport tactical variables can be classified into 3 principal types: occupied space, total field coverage by several players; exploration space, the mean location (+/- standard deviations in X- and Y-directions) of the player/team during the entire game; and dominant/influence space, the region the players can reach before any other players. Most of the studies, i.e., 55%, did not include goalkeepers (GKs) and total playing space to assess occupied space, however, several proposed new variables that considered that all playing space could be "played" (i.e. effective free-space, normalized surface area). Only a collective exploration space variable has been suggested: the major range of the geometrical centre (GC). This suggestion could be applied to assess collective exploration space variables at a sub-system level. The measurement of the dominant/influence space has been based on the Voronoi region (i.e. distance d criteria), but several studies also based their computation on the time (t). In addition, several weighted dominant areas have been suggested. In conclusion, the use of spatial collective tactical variables considering the principal structural traits of each team sport (e.g. players of both teams, the location of the space with respect to the goal, and the total playing space) is recommended

Since the accelerating development of technology applied to team sports and its subsequent high amount of information available, the need for data mining leads to the use of data reduction techniques such as Principal Component Analysis (PCA). This systematic review aims to identify determinant variables in soccer, basketball and rugby using exploratory factor analysis for, training design, performance analysis and talent identification. Three electronic databases (PubMed, Web of Science, SPORTDiscus) were systematically searched and 34 studies were finally included in the qualitative synthesis. Through PCA, data sets were reduced by 75.07%, and 3.9 ± 2.53 factors were retained that explained 80 ± 0.14% of the total variance. All team sports should be analyzed or trained based on the high level of aerobic capacity combined with adequate levels of power and strength to perform repeated high-intensity actions in a very short time, which differ between team sports. Accelerations and decelerations are mainly significant in soccer, jumps and landings are crucial in basketball, and impacts are primarily identified in rugby. Besides, from these team sports, primary information about different technical/tactical variables was extracted such as (a) soccer: occupied space, ball controls, passes, and shots; (b) basketball: throws, rebounds, and turnovers; or (c) rugby: possession game pace and team formation. Regarding talent identification, both anthropometrics and some physical capacity measures are relevant in soccer and basketball. Although overall, since these variables have been identified in different investigations, further studies should perform PCA on data sets that involve variables from different dimensions (technical, tactical, conditional).

Ultra-wide band (UWB) based local positioning systems (LPS) are based on devices and a portable antenna set. The optimal installation height of the antennae is crucial to ensure data accuracy. Collective variables are metrics that consider at least two pairs of coordinates, which may lead to lower precision than an individual one. Therefore, the aim of this study was to compare the influence of antenna height with collective metrics using a UWB (i.e., IMU; WIMU PRO™, RealTrack Systems, Almeria, Spain) based LPS. Data acquisition was carried out in a basketball court measuring 28 × 15 m. Five devices were used; one of which was carried by a healthy and well-trained athlete (age: 38 years, mass: 76.34 kg, height 1.70 m), while each of the remaining four was positioned on a tripod in one of the four corners of the court. Four kinds of variables were extracted: (1) static distances, (2) dynamic distances, (3) static areas and (4) dynamic areas in all antenna installation modes of 0.15, 1.30 and 2.00 m. The results showed that the antenna of 1.30 m provided better accuracy for all measures (% difference range from −0.94 to 1.17%) followed by the antenna of 2.00 m (% difference range from −2.50 to 2.15%), with the antenna of 0.15 m providing the worst accuracy level (% difference range from −1.05 to 3.28%). Overall, the measurements of distance metrics showed greater accuracy than area metrics (distance % difference range from −0.85 to 2.81% and area % difference range from −2.50 to 3.28). In conclusion, the height of the antennae in basketball courts should be similar to the height at which the devices are attached to a player’s upper back. However, as the precision is sensitive to the magnitude of the measure, further studies should assess the effects of the relative height of antennae in team sports with greater playing spaces.

Although many studies on collective tactical behaviour have been published in the last decade, no study has revised and summarized the findings provided for futsal. The main aim of this systematic review was to identify and discuss the geometrical centre (GC), distance and area tactical variables used to assess team behaviour in futsal. In addition, it summarizes the findings on the tactical response during futsal competition and training. A systematic review of the relevant articles provided on futsal was carried out using seven electronic databases (SPORTDiscus, ProQuest, Cochrane Plus, Scopus, Google Scholar, PubMed and Web of Science) until September 25, 2019. From a total of 1,209 studies initially found, 12 were included in the qualitative synthesis. There were some trends in the analysis of positional data in futsal with the most relevant situations analysed being 1 vs 1 and 5 vs 4+Goalkeeper. The distances and angles between two points were the most assessed tactical variables. Five types of distance variables were used to assess collective tactical behaviour in futsal: GC-GC, GC-player, player-player, player-ball and player-space. Pressure (GC-GC) was greater in shots on goal than in tackles during professional futsal matches. Area variables were reduced to occupied space, exploration space and dominant area. Occupied space was measured only during competition while the dominant area was measured only during training sessions. The surface area and dominant regions were greater when players were attacking in comparison to when they were defending. In addition, two non-linear techniques (i.e. relative phase and entropy) were applied to analyse synchronisation and complexity and regularity or predictability. Defenders were highly synchronous, while attackers tried to break this coordination to achieve possibilities for action. Task constraints are suitable to induce different regularity patterns. This review is an opportunity to develop studies aimed at bridgi

173 p., La tesis doctoral, elaborada en formato clásico, está compuesta por cuatro capítulos: (1) contextualización de la tesis doctoral, (2) objetivos de la tesis doctoral, (3) identificación, análisis de la computación, evaluación crítica y futuras consideraciones de las variables del comportamiento táctico colectivo y de las técnicas de análisis no lineal basado en el dato de posicionamiento en los deportes de equipo y (4) evaluación de la calidad de la medida obtenida mediante la tecnología de radio frecuencia en la medición de las variables de comportamiento táctico colectivo en deportes de equipo: un criterio estándar de calidad.Puesto que la tesis doctoral versará sobre el comportamiento táctico colectivo en los deportes de equipo, el Capítulo 1 analizará los conceptos deporte colectivo y comportamiento táctico colectivo basándose en distintos enfoques. Además, el Capítulo 3 constará de una revisión sistemática que identificará las variables tácticas originales y las técnicas de análisis no lineal empleadas hasta la fecha para analizar el comportamiento táctico colectivo en los deportes de equipo. La tesis doctoral ha considerado el dato de posicionamiento para el análisis del comportamiento táctico colectivo. Puesto que la calidad de la medida es un aspecto fundamental en este proceso, el Capítulo 4 propondrá una herramienta de valoración (i.e., ¿quality criteria standard¿) sobre el proceso de obtención del dato mediante tecnología de radio-frecuencia. De manera complementaria, el último capítulo constará de un estudio preliminar y un estudio de campo con el objetivo de indagar en uno de los criterios considerados en el ¿quality criteria standard¿: el impacto del número de datos insertados por segundo en la medición de las variables tácticas colectivas.

Motor behavior assessment during games could help physical education teachers and team coaches to design effective and efficient motor interventions. This study aimed to assess the variability of the physical and behavioral responses during continued practice of the game tail tag with a ball. Sixteen Spanish youth soccer players from an under-14 team played tail tag, with a ball, during four sessions (5 repetitions of 1 min per session). Physical (i.e., Total Distance (TD) and PlayerLoad (PL)) and behavioral (i.e., Surface Area (SA) and change in the Geometrical Centre position (cGCp)) dimensions were assessed with a local positioning system. The mean of the five series of each session was considered for further statistical analysis. The main finding was that the external load decreased (d = small − large) and the use of space varied during the continued practice of tail tag. Initially, SA increased substantially (d = large) and cGCp decreased slightly (d = small), and then both variables tended to stabilize. This suggests that after several repetitions of the same motor game, physical education teachers and team sports coaches should use this again later, modifying this or proposing new motor games where players respond to these activities that consist in greater uncertainty than to well-known motor games.

The use of valid, accurate and reliable systems is decisive for ensuring the data collection and correct interpretation of the values. Several studies have reviewed these aspects on the measurement of movement patterns by high-definition cameras (VID) and Global Positioning Systems (GPS) but not by Local Positioning Systems (LPS). Thus, the aim of the review was to summarize the evidence about the validity and reliability of LPS technology to measure movement patterns at human level in outdoor and indoor stadium-scale. The authors systematically searched three electronic databases (PubMed, Web of Science and SPORTDiscus) to extract studies published before 21 October 2019. A Boolean search phrase was created to include sport (population; 8 keywords), search terms relevant to intervention technology (intervention technology; 6 keywords) and measure outcomes of the technology (outcomes; 7 keywords). From the 62 articles found, 16 were included in the qualitative synthesis. This systematic review revealed that the tested LPS systems proved to be valid and accurate in determining the position and estimating distances and speeds, although they were not valid or their accuracy decreased when measuring instantaneous speed, peak accelerations or decelerations or monitoring particular conditions (e.g., changes of direction, turns). Considering the variability levels, the included studies showed that LPS provide a reliable way to measure distance variables and athletes’ average speed.

The aim of the study was the identification, computational examination, critical assessment and future considerations of distance variables to assess collective tactical behaviour in team invasion sports by positional data. A total of 3973 documents were initially retrieved. Finally, 72 articles met the inclusion criteria, but only 26 suggested original tactical variables based on the distance variables. The distance variables can be classified into player–player, player–space, player–ball, and Geometrical Centre (GC)–GC /player/space/goal. In addition, several nonlinear techniques have been used to analyse the synchronisation and predictability of the distance variables in team invasion sports. Player–opponent distance is of special interest in those sports in which man-marking is commonly used, and in the micro-structure close to scoring situations in all sports. In addition, player–player distances are used to measure the length and the width of the team and player–GC distance to assess the dispersion of the team. Player–space distances have been measured to assess the distance of the player/team-line to relevant areas of the playing space. Several techniques have been applied to analyse the synchronisation (i.e., Hilbert transformation and cluster analyses) and the complexity and regularity or predictability (i.e., approximate entropies, sample entropy, cross-sample entropy and average mutual information) of the distance variables in team invasion sports, revealing the lack of consensus. Although the distance variables may be interesting tactical variables when considered in isolation, it would be enriching to analyse the relationship among these variables.

173 p., La tesis doctoral, elaborada en formato clásico, está compuesta por cuatro capítulos: (1) contextualización de la tesis doctoral, (2) objetivos de la tesis doctoral, (3) identificación, análisis de la computación, evaluación crítica y futuras consideraciones de las variables del comportamiento táctico colectivo y de las técnicas de análisis no lineal basado en el dato de posicionamiento en los deportes de equipo y (4) evaluación de la calidad de la medida obtenida mediante la tecnología de radio frecuencia en la medición de las variables de comportamiento táctico colectivo en deportes de equipo: un criterio estándar de calidad.Puesto que la tesis doctoral versará sobre el comportamiento táctico colectivo en los deportes de equipo, el Capítulo 1 analizará los conceptos deporte colectivo y comportamiento táctico colectivo basándose en distintos enfoques. Además, el Capítulo 3 constará de una revisión sistemática que identificará las variables tácticas originales y las técnicas de análisis no lineal empleadas hasta la fecha para analizar el comportamiento táctico colectivo en los deportes de equipo. La tesis doctoral ha considerado el dato de posicionamiento para el análisis del comportamiento táctico colectivo. Puesto que la calidad de la medida es un aspecto fundamental en este proceso, el Capítulo 4 propondrá una herramienta de valoración (i.e., ¿quality criteria standard¿) sobre el proceso de obtención del dato mediante tecnología de radio-frecuencia. De manera complementaria, el último capítulo constará de un estudio preliminar y un estudio de campo con el objetivo de indagar en uno de los criterios considerados en el ¿quality criteria standard¿: el impacto del número de datos insertados por segundo en la medición de las variables tácticas colectivas.

The use of valid, accurate and reliable systems is decisive for ensuring the data collection and correct interpretation of the values. Several studies have reviewed these aspects on the measurement of movement patterns by high-definition cameras (VID) and Global Positioning Systems (GPS) but not by Local Positioning Systems (LPS). Thus, the aim of the review was to summarize the evidence about the validity and reliability of LPS technology to measure movement patterns at human level in outdoor and indoor stadium-scale. The authors systematically searched three electronic databases (PubMed, Web of Science and SPORTDiscus) to extract studies published before 21 October 2019. A Boolean search phrase was created to include sport (population; 8 keywords), search terms relevant to intervention technology (intervention technology; 6 keywords) and measure outcomes of the technology (outcomes; 7 keywords). From the 62 articles found, 16 were included in the qualitative synthesis. This systematic review revealed that the tested LPS systems proved to be valid and accurate in determining the position and estimating distances and speeds, although they were not valid or their accuracy decreased when measuring instantaneous speed, peak accelerations or decelerations or monitoring particular conditions (e.g., changes of direction, turns). Considering the variability levels, the included studies showed that LPS provide a reliable way to measure distance variables and athletes’ average speed.

Although many studies on collective tactical behaviour have been published in the last decade, no study has revised and summarized the findings provided for futsal. The main aim of this systematic review was to identify and discuss the geometrical centre (GC), distance and area tactical variables used to assess team behaviour in futsal. In addition, it summarizes the findings on the tactical response during futsal competition and training. A systematic review of the relevant articles provided on futsal was carried out using seven electronic databases (SPORTDiscus, ProQuest, Cochrane Plus, Scopus, Google Scholar, PubMed and Web of Science) until September 25, 2019. From a total of 1,209 studies initially found, 12 were included in the qualitative synthesis. There were some trends in the analysis of positional data in futsal with the most relevant situations analysed being 1 vs 1 and 5 vs 4+Goalkeeper. The distances and angles between two points were the most assessed tactical variables. Five types of distance variables were used to assess collective tactical behaviour in futsal: GC-GC, GC-player, player-player, player-ball and player-space. Pressure (GC-GC) was greater in shots on goal than in tackles during professional futsal matches. Area variables were reduced to occupied space, exploration space and dominant area. Occupied space was measured only during competition while the dominant area was measured only during training sessions. The surface area and dominant regions were greater when players were attacking in comparison to when they were defending. In addition, two non-linear techniques (i.e. relative phase and entropy) were applied to analyse synchronisation and complexity and regularity or predictability. Defenders were highly synchronous, while attackers tried to break this coordination to achieve possibilities for action. Task constraints are suitable to induce different regularity patterns. This review is an opportunity to develop studies aimed at bridgi

The aim of the study was the identification, computational examination, critical assessment and future considerations of distance variables to assess collective tactical behaviour in team invasion sports by positional data. A total of 3973 documents were initially retrieved. Finally, 72 articles met the inclusion criteria, but only 26 suggested original tactical variables based on the distance variables. The distance variables can be classified into player–player, player–space, player–ball, and Geometrical Centre (GC)–GC /player/space/goal. In addition, several nonlinear techniques have been used to analyse the synchronisation and predictability of the distance variables in team invasion sports. Player–opponent distance is of special interest in those sports in which man-marking is commonly used, and in the micro-structure close to scoring situations in all sports. In addition, player–player distances are used to measure the length and the width of the team and player–GC distance to assess the dispersion of the team. Player–space distances have been measured to assess the distance of the player/team-line to relevant areas of the playing space. Several techniques have been applied to analyse the synchronisation (i.e., Hilbert transformation and cluster analyses) and the complexity and regularity or predictability (i.e., approximate entropies, sample entropy, cross-sample entropy and average mutual information) of the distance variables in team invasion sports, revealing the lack of consensus. Although the distance variables may be interesting tactical variables when considered in isolation, it would be enriching to analyse the relationship among these variables.

Motor behavior assessment during games could help physical education teachers and team coaches to design effective and efficient motor interventions. This study aimed to assess the variability of the physical and behavioral responses during continued practice of the game tail tag with a ball. Sixteen Spanish youth soccer players from an under-14 team played tail tag, with a ball, during four sessions (5 repetitions of 1 min per session). Physical (i.e., Total Distance (TD) and PlayerLoad (PL)) and behavioral (i.e., Surface Area (SA) and change in the Geometrical Centre position (cGCp)) dimensions were assessed with a local positioning system. The mean of the five series of each session was considered for further statistical analysis. The main finding was that the external load decreased (d = small − large) and the use of space varied during the continued practice of tail tag. Initially, SA increased substantially (d = large) and cGCp decreased slightly (d = small), and then both variables tended to stabilize. This suggests that after several repetitions of the same motor game, physical education teachers and team sports coaches should use this again later, modifying this or proposing new motor games where players respond to these activities that consist in greater uncertainty than to well-known motor games.

The aim of the present study was to systematically review the origin and modifications of the geometrical centre (GC) in the assessment of team behaviour in team sports. Studies were identified following the PRISMA guidelines and PICO design for systematics reviews in four electronic databases (PubMed, SPORTDiscus, ProQuest Central, and Web of Sciences). A total of 3,973 documents were initially retrieved, of which 1,779 were duplicates. After checking 2,178, another 36 were added from the references of the studies. 72 articles met de inclusion criteria and 7 were included for the systematic review. Habitually, the GC is computed as the mean [X,Y] of several or all players in the sports team. Despite the relevance of the location of the players with respect to the goal, habitually, the goalkeeper/target has not been considered in the measurement of the GC. Two techniques (i.e. Hilbert transformation and cluster analyses) have been applied to analyse the synchronisation (i.e. relative phase) and the average mutual information (AMI) to assess the complexity and regularity or predictability of the GC in team sports. Since the GC does not consider the goalkeepers and team dispersion, this measure should be interpreted with caution, but together with other tactical variables can provide interesting information for team sports technical staff., El objetivo de este estudio fue revisar sistemáticamente el origen y las modificaciones del centro geométrico (GC) en la evaluación del comportamiento táctico colectivo en los deportes de equipo. La identificación de los estudios se llevó a cabo en cuatro bases de datos (PubMed, SPORTDiscus, ProQuest Central, and Web of Sciences) siguiendo la guía PRISMA y el diseño PICO para revisiones sistemáticas. Un total de 3,973 documentos fueron inicialmente recuperados, de los cuales 1,779 eran duplicados. Después de analizar 2,178 artículos, otros 36 fueron añadidos tras ser rescatados de las referencias bibliográficas. 72 artículos cumplieron los criterios de inclusión, de los cuales 7 sugirieron variables tácticas originales relacionadas con el posicionamiento del GC. Dos cálculos diferentes han sido propuestos para medir el GC en los deportes de equipo, siendo la media [X, Y] de varios o todos los jugadores del equipo el más utilizado. El primer cálculo del GC fue propuesto en fútbol y consideró al portero, pero este jugador especial no suele ser incluido en la medición. La ubicación de los jugadores con respecto a la diana no ha sido considerada para valorar el GC en deportes de equipo como el fútbol. Por lo tanto, las variables tácticas complementarias, como por ejemplo la distancia entre el portero o la portería y el GC, podrían asociarse con el GC para evaluar la posición relativa de varios jugadores en el espacio de juego. Dos técnicas distintas (i.e. la transformación de Hilbert y el cluster analyses) han sido aplicadas para analizar la sincronización (i.e. la fase relativa) y el average mutual information (AMI) para evaluar la complejidad y regularidad o previsibilidad del GC en los deportes de equipo.

Currently, it exists a study increase related to the external load assessment through inertial devices in invasion team sports. The monitoring is has been performing in one anatomical location depending of the manufacturer recommendations. The challenge arises when the single location measurement does not detect the total load of the body and a multi-location assessment is required to accurately evaluate the athlete’s body workload. Therefore, the purpose of the present study is to design and validate a field-test battery for external multi-location workload assessment in the most common displacements in invasion team sports. Five tests composed the battery that evaluate the following capacities/abilities: (a) aerobic, linear displacement; (b) lactic anaerobic capacity, acceleration and deceleration, (c) non-lactic anaerobic capacity, curvilinear displacement (d) elastic capacity, jump, (e) conditional physical capacity, small-sided games. Therefore, using this group of tests will provide the team staff with a global overview and an individualized multi-location workload profile of the athlete., En la actualidad, existe un creciente interés en la evaluación de la carga externa mediante dispositivos inerciales en deportes de invasión. La monitorización se ha estado realizando en una única ubicación anatómica en función de las especificaciones del fabricante. El reto surge cuando la medición en una única ubicación no detecta la carga global del cuerpo y una evaluación en diferentes ubicaciones es requerida para evaluar de forma precisa la carga externa soportada por el deportista. Por tanto, el objetivo del presente estudio es el diseño y validación de una batería de pruebas de campo para la evaluación de carga interna y externa multi-ubicación en relación con los desplazamientos en deportes de invasión. La evaluación está compuesta por un total de cinco pruebas que evalúan las siguientes capacidades/habilidades: (a) aeróbica, desplazamiento lineal; (b) capacidad anaeróbica láctica, aceleración y desaceleración, (c) capacidad anaeróbica aláctica, desplazamiento curvilíneo (d) capacidad elástica, salto, (e) capacidad física condicional, juegos reducidos modificados. Por ello, la evaluación mediante la batería propuesta aportará al cuerpo técnico una visión global y multi-ubicación de la condición física individualizada del deportista.

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 (r2= 0.61; F= 26.17; p< 0.001) and 37% by the heart rate variation in the 31 to 35 km section (r2= 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., 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 (42195 m) en cercanía al mar bajo un índice térmico de 27.8 ± 3.52 ºC 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 variaciónde 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 (r2= 0.61; F= 26.17; p< 0.001) y por la variabilidad de la frecuencia cardíaca en el lapso de 31 a 35 km (r2= 0.37; F= 10.38; p< 0.001) respectivamente. En conclusión, el índice térmico provoca una disminución en el ritmo de la velocidad, siendo este efecto mayor en la segunda mitad de la carrera. Por lo anterior, entrenadores deben de planificar entrenamientos y estrategias para mitigar el impacto de estas condiciones en el desempeño físico y fisiológico de los corredores amateur.

173 p., La tesis doctoral, elaborada en formato clásico, está compuesta por cuatro capítulos: (1) contextualización de la tesis doctoral, (2) objetivos de la tesis doctoral, (3) identificación, análisis de la computación, evaluación crítica y futuras consideraciones de las variables del comportamiento táctico colectivo y de las técnicas de análisis no lineal basado en el dato de posicionamiento en los deportes de equipo y (4) evaluación de la calidad de la medida obtenida mediante la tecnología de radio frecuencia en la medición de las variables de comportamiento táctico colectivo en deportes de equipo: un criterio estándar de calidad.Puesto que la tesis doctoral versará sobre el comportamiento táctico colectivo en los deportes de equipo, el Capítulo 1 analizará los conceptos deporte colectivo y comportamiento táctico colectivo basándose en distintos enfoques. Además, el Capítulo 3 constará de una revisión sistemática que identificará las variables tácticas originales y las técnicas de análisis no lineal empleadas hasta la fecha para analizar el comportamiento táctico colectivo en los deportes de equipo. La tesis doctoral ha considerado el dato de posicionamiento para el análisis del comportamiento táctico colectivo. Puesto que la calidad de la medida es un aspecto fundamental en este proceso, el Capítulo 4 propondrá una herramienta de valoración (i.e., ¿quality criteria standard¿) sobre el proceso de obtención del dato mediante tecnología de radio-frecuencia. De manera complementaria, el último capítulo constará de un estudio preliminar y un estudio de campo con el objetivo de indagar en uno de los criterios considerados en el ¿quality criteria standard¿: el impacto del número de datos insertados por segundo en la medición de las variables tácticas colectivas.

The use of valid, accurate and reliable systems is decisive for ensuring the data collection and correct interpretation of the values. Several studies have reviewed these aspects on the measurement of movement patterns by high-definition cameras (VID) and Global Positioning Systems (GPS) but not by Local Positioning Systems (LPS). Thus, the aim of the review was to summarize the evidence about the validity and reliability of LPS technology to measure movement patterns at human level in outdoor and indoor stadium-scale. The authors systematically searched three electronic databases (PubMed, Web of Science and SPORTDiscus) to extract studies published before 21 October 2019. A Boolean search phrase was created to include sport (population; 8 keywords), search terms relevant to intervention technology (intervention technology; 6 keywords) and measure outcomes of the technology (outcomes; 7 keywords). From the 62 articles found, 16 were included in the qualitative synthesis. This systematic review revealed that the tested LPS systems proved to be valid and accurate in determining the position and estimating distances and speeds, although they were not valid or their accuracy decreased when measuring instantaneous speed, peak accelerations or decelerations or monitoring particular conditions (e.g., changes of direction, turns). Considering the variability levels, the included studies showed that LPS provide a reliable way to measure distance variables and athletes’ average speed.

Although many studies on collective tactical behaviour have been published in the last decade, no study has revised and summarized the findings provided for futsal. The main aim of this systematic review was to identify and discuss the geometrical centre (GC), distance and area tactical variables used to assess team behaviour in futsal. In addition, it summarizes the findings on the tactical response during futsal competition and training. A systematic review of the relevant articles provided on futsal was carried out using seven electronic databases (SPORTDiscus, ProQuest, Cochrane Plus, Scopus, Google Scholar, PubMed and Web of Science) until September 25, 2019. From a total of 1,209 studies initially found, 12 were included in the qualitative synthesis. There were some trends in the analysis of positional data in futsal with the most relevant situations analysed being 1 vs 1 and 5 vs 4+Goalkeeper. The distances and angles between two points were the most assessed tactical variables. Five types of distance variables were used to assess collective tactical behaviour in futsal: GC-GC, GC-player, player-player, player-ball and player-space. Pressure (GC-GC) was greater in shots on goal than in tackles during professional futsal matches. Area variables were reduced to occupied space, exploration space and dominant area. Occupied space was measured only during competition while the dominant area was measured only during training sessions. The surface area and dominant regions were greater when players were attacking in comparison to when they were defending. In addition, two non-linear techniques (i.e. relative phase and entropy) were applied to analyse synchronisation and complexity and regularity or predictability. Defenders were highly synchronous, while attackers tried to break this coordination to achieve possibilities for action. Task constraints are suitable to induce different regularity patterns. This review is an opportunity to develop studies aimed at bridgi

The aim of the study was the identification, computational examination, critical assessment and future considerations of distance variables to assess collective tactical behaviour in team invasion sports by positional data. A total of 3973 documents were initially retrieved. Finally, 72 articles met the inclusion criteria, but only 26 suggested original tactical variables based on the distance variables. The distance variables can be classified into player–player, player–space, player–ball, and Geometrical Centre (GC)–GC /player/space/goal. In addition, several nonlinear techniques have been used to analyse the synchronisation and predictability of the distance variables in team invasion sports. Player–opponent distance is of special interest in those sports in which man-marking is commonly used, and in the micro-structure close to scoring situations in all sports. In addition, player–player distances are used to measure the length and the width of the team and player–GC distance to assess the dispersion of the team. Player–space distances have been measured to assess the distance of the player/team-line to relevant areas of the playing space. Several techniques have been applied to analyse the synchronisation (i.e., Hilbert transformation and cluster analyses) and the complexity and regularity or predictability (i.e., approximate entropies, sample entropy, cross-sample entropy and average mutual information) of the distance variables in team invasion sports, revealing the lack of consensus. Although the distance variables may be interesting tactical variables when considered in isolation, it would be enriching to analyse the relationship among these variables.

Motor behavior assessment during games could help physical education teachers and team coaches to design effective and efficient motor interventions. This study aimed to assess the variability of the physical and behavioral responses during continued practice of the game tail tag with a ball. Sixteen Spanish youth soccer players from an under-14 team played tail tag, with a ball, during four sessions (5 repetitions of 1 min per session). Physical (i.e., Total Distance (TD) and PlayerLoad (PL)) and behavioral (i.e., Surface Area (SA) and change in the Geometrical Centre position (cGCp)) dimensions were assessed with a local positioning system. The mean of the five series of each session was considered for further statistical analysis. The main finding was that the external load decreased (d = small − large) and the use of space varied during the continued practice of tail tag. Initially, SA increased substantially (d = large) and cGCp decreased slightly (d = small), and then both variables tended to stabilize. This suggests that after several repetitions of the same motor game, physical education teachers and team sports coaches should use this again later, modifying this or proposing new motor games where players respond to these activities that consist in greater uncertainty than to well-known motor games.