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

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

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

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

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

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

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

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

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

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

Outpatient Assessment of Mechanical Load, Heat Strain and Dehydration as Causes of Transitional Acute Kidney Injury in Endurance Trail Runners.

BACKGROUND: This study aimed to globally assess heat strain, dehydration, and mechanical load as acute kidney injury (AKI) indicators in amateur endurance trail athletes during a 35.3 km run. METHODS: Thirty amateur experienced trail runners completed an endurance trail run (total positive ascend 1815 m). The following assessments were performed at four measurement time points (pre-, during, immediately post [-post0h], and after 24 h of the finish of the run [-post24h]): serum test (creatinine, blood ureic nitrogen, albumin, creatine kinase, blood ureic nitrogen: creatinine ratio, creatinine clearance, and glomerular filtration rate), mechanical load (impacts and Player Load), heat strain and dehydration (hematocrit, urine solids, body weight and urine specific gravity), pain and exertion perception (rate of perceived exertion, lumbar and bipodal, and one-leg squat pain), and urinalysis (pH, protein, glucose, erythrocytes, and urine specific gravity). RESULTS: There were pre vs. post0h changes in all serum biomarkers (F = 5.4-34.45, p < 0.01). The change in these biomarkers correlated with an increase in mechanical load indicators (r = 0.47-59, p < 0.05). A total of 40% and 23.4% of participants presented proteinuria and hematuria, respectively. Pain and perceived exertion increased significantly due to effort made during the endurance trail running (F = 4.2-176.4, p < 0.01). CONCLUSIONS: Endurance trail running may lead to an increase in blood and urine indicators of transitional AKI. The difference in blood and urine markers was significantly related to the mechanical load during running, suggesting potential kidney overload and cumulative mechanical load.

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

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

Efecto agudo del estiramiento estático y dinámico sobre el rendimiento y la percepción de esfuerzo en ejercicio contrarresistencia / Acute Effect of Static and Dynamic Stretching on Performance and Perception of Extertion in Resistance Exercise

Resumen El propósito de esta investigación fue comparar el efecto agudo del estiramiento estático y dinámico entre series sobre el rendimiento y la percepción de esfuerzo en la ejecución de un ejercicio de contrarresistencia. Participaron un total de 30 sujetos masculinos físicamente activos y aparentemente sanos con experiencia mínima de cuatro meses en el entrenamiento contrarresistencia, con un promedio de edad: 23.4 ± 3.2 años, un peso: 71.7 ± 6.0 kg, talla: 172 ± 6.1cm, porcentaje de grasa: 16.3 ± 5.3 % y masa magra: 34.5 ± 3.2 kg. Díez sujetos en cada grupo fueron asignados de manera aleatoria a las condiciones experimentales grupo control (sin estiramiento entre series), grupo con estiramiento estático entre series (EE) y grupo con estiramiento dinámico entre series (ED) al ser los grupos homogéneos en nivel de fuerza en el 1RM (F (2,29) = 0.77, p = .47), los sujetos fueron sometidos a un estímulo de 4 series al fallo con el 80 % del 1RM . Los datos obtenidos fueron analizados mediante un ANOVA de una vía. Los resultados obtenidos indican que no se registraron diferencias estadísticamente significativas en el comportamiento de las variables relacionadas con el rendimiento: (F (2,29) = 1.37, p = .27, ωp 2 = .02), en el índice de fatiga, (F (2,29) = 2.25, p = .12, ωp 2 = .07) en el número total de repeticiones, tampoco se observaron diferencias estadísticamente significativas, en cuanto a la percepción de esfuerzo (F (2,29) = 0.46, p = .63, ωp 2 = -.03). Se concluye que el rendimiento expresado en el índice de fatiga y el número total de repeticiones, así como la percepción de esfuerzo, no se ven afectados de manera aguda por el uso de estiramiento entre series, sea de tipo estático o dinámico.

Abstract The main objective of this study was to compare the acute effect of static and dynamic inter-set stretching on performance during resistance training. Thirty physically active and apparently healthy male subjects took part in the study with a minimum experience of four months in resistance training. The mean of age was 23.4 ± 3.2 years; the body mass was 71.7 ± 6.0 kg; the height was 172 ± 6.1cm; the body fat percentage represented 16. 3 ± 5.3%; and the lean mass was 34.5 ± 3.2 kg. Then, subjects were randomly distributed in groups: control group (without stretching inter series), group with static inter series stretching (SS), and group with dynamic inter series stretching (DS). The groups were homogeneous in the 1RM (F (2.29) = 0.77, p = .47). Data were analyzed using a one-way ANOVA. The results showed that there were no statistically significant differences in the behavior of the variables related to performance: (F (2,29) = 1.37, p = .27, ωp 2 = .02) in the fatigue index, (F (2,29) = 2.25, p =.12, ωp 2 = .07) in the total number of repetitions. Neither significant differences were observed in the perceived exertion (F (2,29) = 0.46, p =.63, ωp 2 = -.03). It is concluded that the performance expressed in the fatigue index and total number of repetitions, as well as the perceived exertion, is not acutely affected by the use of inter-series static or dynamic stretching.

Resumo O objetivo do presente estudo foi comparar o efeito agudo do alongamento estático e dinâmico entre series sobre o desempenho e o esforço percebido na execução de um exercício de contra-resistência. Um total de 30 indivíduos do sexo masculino fisicamente ativos e aparentemente saudáveis, com pelo menos quatro meses de experiência em treinamento de contra-resistência, com idade média: 23,4 ± 3,2 anos, peso: 71,7 ± 6,0 kg, altura: 172 ± 6,1cm, percentual de gordura: 16,3 ± 5,3 % e massa magra: 34,5 ± 3,2 kg. Dez sujeitos em cada grupo foram designados aleatoriamente para o grupo de controle de condições experimentais (sem alongamento entre séries), grupo de alongamento estático entre séries (EE) e grupo de alongamento dinâmico entre séries (ED), pois os grupos foram homogêneos no nível de força a 1RM (F(2,29) = 0,77, p = .47), os sujeitos foram submetidos a um estímulo de 4 séries em caso de falha com 80% de 1RM . Os dados obtidos foram analisados por meio de uma ANOVA de uma via. Os resultados indicam que não houve diferenças estatisticamente significativas no comportamento das variáveis relacionadas ao desempenho: (F(2,29) = 1,37, p = .27, ωp2 = .02), no índice de fadiga, (F(2,29) = 2,25, p = .12, ωp2 = .07) no número total de repetições, nem houve diferenças estatisticamente significativas na percepção do esforço (F(2,29) = 0,46, p = .63, ωp2 = -.03). Conclui-se que o desempenho expresso no índice de fadiga e o número total de repetições, bem como a percepção de esforço, não são agudamente afetados pelo uso de alongamento entre conjuntos, seja estático ou dinâmico.

Data Mining to Select Relevant Variables Influencing External and Internal Workload of Elite Blind 5-a-Side Soccer.

(1) Background: Data mining has turned essential when exploring a large amount of information in performance analysis in sports. This study aimed to select the most relevant variables influencing the external and internal load in top-elite 5-a-side soccer (Sa5) using a data mining model considering some contextual indicators as match result, body mass index (BMI), scoring rate and age. (2) Methods: A total of 50 top-elite visually impaired soccer players (age 30.86 ± 11.2 years, weight 77.64 ± 9.78 kg, height 178.48 ± 7.9 cm) were monitored using magnetic, angular and rate gyroscope (MARG) sensors during an international Sa5 congested fixture tournament.; (3) Results: Fifteen external and internal load variables were extracted from a total of 49 time-related and peak variables derived from the MARG sensors using a principal component analysis as the most used data mining technique. The principal component analysis (PCA) model explained 80% of total variance using seven principal components. In contrast, the first principal component of the match was defined by jumps, take off by 24.8% of the total variance. Blind players usually performed a higher number of accelerations per min when losing a match. Scoring players execute higher DistanceExplosive and Distance21-24 km/h. And the younger players presented higher HRAVG and AccMax. (4) Conclusions: The influence of some contextual variables on external and internal load during top elite Sa5 official matches should be addressed by coaches, athletes, and medical staff. The PCA seems to be a useful statistical technique to select those relevant variables representing the team's external and internal load. Besides, as a data reduction method, PCA allows administrating individualized training loads considering those relevant variables defining team load behavior.

Exertional rhabdomyolysis and acute kidney injury in endurance sports: A systematic review.

The increase of wide-spread participation in endurance events in sports such as open water swimming, cycling, running and triathlons, has given rise to a concern about potential implications for renal function and kidney health. This study aimed to delve into the findings on exertional rhabdomyolysis (ER) and acute kidney injury (AKI) in endurance sports, emphasizing the diagnostic criteria used, physical and environmental contextual conditions in which ER and AKI are reported. Following PRISMA guidelines for systematic reviews and meta-analysis, topic related studies were searched digital sources (from 2009 to 2020). Studies with biomarkers of ER and AKI reported in endurance or ultra-endurance events were included. A total of 43 publications (sample = 813) were extracted, and 345 (43.5%) individuals were diagnosed with ER (creatinine kinase > 5000 UI/L) and 130 (16.39%) with ER + AKI (creatinine ≥ 1.88 mg/dL). Out of the total cases of ER + AKI, 96.92% were in ultra-endurance runners. There were inconsistences between studies in diagnosis criteria for ER and AKI, which represented a difficulty in the interpretation of the data. Increased levels of muscle and kidney injury immediately after endurance events were reported, but after 5.86 days these levels usually returned to baseline. There is a lack of knowledge around the potential of repeated ER and AKI predisposing to long-term chronic kidney disease. More accurate markers for subclinical and functional AKI diagnosis are needed in the analysis of kidney health after endurance events. ER and AKI are serious clinical problems with significant morbidity. Further research may be in order to help define future prevention strategies.

Effectiveness of beetroot juice derived nitrates supplementation on fatigue resistance during repeated-sprints: a systematic review.

In recent decades, the search for non-doping substances that enhance sports performance has increased. Ergogenic aids such as beetroot juice (BRJ) and BRJ rich in nitrates (NO3-) are widely used to cause physiological benefits that may lead to physical improvements. Therefore, the purpose of this systematic review was to explore the knowledge reported to date on the NO3- derived from BRJ intake effect on fatigue resistance during repeated sprints. A digital search was conducted following systematic review guidelines, and 18 studies met inclusion criteria from a total of 209 articles. In a third of the selected studies, the consumption of beet juice rich in NO3- contributes to an increase in nitrites in plasma that led to the rise in peak power, mean power, number of sprint repetitions, total work and time to task failure, and causes a decrease in fatigue index and sprints times. Some different dose has been proposed for both chronic and acute protocols. It seems that a chronic intake of ∼5-6 mmol of NO3- in 70 ml of BRJ, twice a day, for a minimum of 3-6 days could lead to a fatigue resistance improvement during repeated sprints. Besides, acute intake of NO3- 2.5-3 h before physical exertion or a dose of 250 ml/d to 500 ml/d of BRJ could lead to similar effective results. This systematic review presents some improvements (1.2-5.38%) in fatigue resistance during repeated sprints when consuming BRJ derived NO3-. The in-field practical meaning of these results should be explored.

Proteinuria and Bilirubinuria as Potential Risk Indicators of Acute Kidney Injury during Running in Outpatient Settings.

Background and objectives: The purpose of this study was to explore which urinary markers could indicate acute kidney injury (AKI) during prolonged trail running in outpatient settings. Materials and Methods: Twenty-nine experienced trail runners (age 39.1 ± 8.8 years, weight 71.9 ± 11 kg, height 171.9 ± 8.3 cm) completed a 35 km event (cumulative positive ascend of 1815 m, altitude = 906 to 1178 m.a.s.l.) under a temperature of 25.52 ± 1.98 °C and humidity of 79.25 ± 7.45%). Two participant groups (AKI = 17 and No-AKI = 12) were made according to AKI diagnosis criteria based on pre- and post-race values of serum creatinine (sCr) (an increase of 1.5 times from baseline). Blood and urinalysis were performed immediately pre- and post-race. Results: Pre- vs. post-race differences in sCr and sBUN were found in both AKI and No-AKI groups (p < 0.01). Differences in post-race values were found between groups (p = 0.03). A total of 52% of AKI runners presented significant increases in proteinuria (χ2 = 0.94, p = 0.01) and 47% in bilirubinuria (χ2 = 0.94, p = 0.04). Conversely, No-AKI participants presented no significant increases in urine markers. Conclusions: These study's findings may suggest the potential use of urinalysis as an accessible alternative in the outpatient setting to early identify transitional AKI until a clinical confirmation is performed.

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

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

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

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

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

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

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

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

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

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

Potential Use of Wearable Sensors to Assess Cumulative Kidney Trauma in Endurance Off-Road Running.

(1) Background: This study aimed to explore wearable sensors' potential use to assess cumulative mechanical kidney trauma during endurance off-road running. (2) Methods: 18 participants (38.78 ± 10.38 years, 73.24 ± 12.6 kg, 172.17 ± 9.48 cm) ran 36 k off-road race wearing a Magnetic, Angular Rate and Gravity (MARG) sensor attached to their lower back. Impacts in g forces were recorded throughout the race using the MARG sensor. Two blood samples were collected immediately pre- and post-race: serum creatinine (sCr) and albumin (sALB). (3) Results: Sixteen impact variables were grouped using principal component analysis in four different principal components (PC) that explained 90% of the total variance. The 4th PC predicted 24% of the percentage of change (∆%) of sCr and the 3rd PC predicted the ∆% of sALB by 23%. There were pre- and post-race large changes in sCr and sALB (p ≤ 0.01) and 33% of participants met acute kidney injury diagnosis criteria. (4) Conclusions: The data related to impacts could better explain the cumulative mechanical kidney trauma during mountain running, opening a new range of possibilities using technology to better understand how the number and magnitude of the g-forces involved in off-road running could potentially affect kidney function.

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

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

Accelerometry-Based External Load Indicators in Sport: Too Many Options, Same Practical Outcome?

With the development of new microsensor technology to assess load in sports, some indicators of external load through accelerometry-based data have been created by sport technology companies. Thus, the study aim was to analyze the agreement between different accelerometry-based external load indicators (ABELIs) available in sport science. A U-16 male soccer team was assessed during three official matches, divided by periods, to obtain 3-D accelerometry data (x, y and z axes). An average of 1,420,000 data points was analyzed per axis per player. The ABELIs were calculated using this information, and the agreement between them was explored. The following ABELIs were considered after a literature review: AcelT, Player LoadRT, PlayerLoadTM, Impulse Load, Player LoadRE and Total Load. In order to compare ABELIs, two analyses were performed using: (1) absolute data; and (2) normalized and centered data (Z-scores). In absolute and centered data, very large to nearly perfect correlations (1st period: r > 0.803, p > 0.01; 2nd period: r > 0.919; p > 0.01) were found. Instead, very large differences were found in absolute values (bias = -579,226.6 to 285,931.1; t = -224.66 to 213.91, p < 0.01), and no differences in scaled and centered values (bias = 0; t = 1; p= 1). In conclusion, considering the different output (magnitude and units) among ABELIs, the standardization of a universal index to calculate accelerometer load is needed in order to make possible between-study comparison.

Análisis de sobrepeso y obesidad, niveles de actividad física y autoestima en la niñez del II ciclo escolar del cantón central de Heredia, Costa Rica / Analysis of overweight and obesity, levels of physical activity and self-esteem in childhood of the II school cycle of the central canton of Heredia, Costa Rica

Resumen Objetivo: analizar la prevalencia de sobrepeso y obesidad, el nivel de actividad física y autoestima de la población escolar de II Ciclo del cantón central de Heredia Método: este fue un estudio descriptivo-comparativo transversal en el que se analizaron 442 niños, de cuarto, quinto y sexto grado escolar, de los cuales 234 fueron niños y 208 niñas con una edad entre los 9 y 13 años. Se realizó la medición del peso y la talla para el cálculo del índice de masa corporal, se aplicó el cuestionario de actividad física para niños mayores (PAQ-C) y el cuestionario LAWSEQ para la medición del nivel de autoestima. Resultados: los resultados mostraron un 20.6 % de infantes poseen sobrepeso y 13.6 % presentaron obesidad, en el nivel de actividad física un 29.4 % mostraron un nivel bajo y un 26.7 % baja autoestima. Además, los niños presentaron un nivel de actividad física más alto en comparación con las niñas (F (9) = 2.55; p=0.007). Conclusiones: en función del objetivo, la prevalencia de sobrepeso y obesidad en las niñas y en los niños fue de un 34.2 %. Un 30% presentó altos niveles de sedentarismo y un 27 % bajos niveles de autoestima. Estos datos indican la necesidad de generar opciones de intervención en los diferentes niveles educativos, fundamentalmente, trabajando en equipo con entes gubernamentales del país.

Abstract Objetive: analyze the prevalence of overweight and obesity, the level of physical activity and self-esteem of the school population of fourth, fifth and sixth grades of the Central District of Heredia. Method: The descriptive-comparative and transversal study analyzed 442 children, 234 boys and 208 girls between 9 and 13 years old. It was measured the weight and height to calculate the body mass index, the Physical Activity Questionnaire for Children (PAQ-C) and Lawrence's Self-Esteem Questionnaire (LAWSEQ). Results: the results suggest 20.6 % of infants with overweight and 13.6 % with obesity, 29.4 % indicated a low level of physical activity and 26.7 % with low self-esteem. In addition, boys report a higher level of physical activity compared to girls (F (9) =2.55; p=0.007). Conclusions: According to the objective, the prevalence of overweight and obesity in girls and boys was 34.2 %, 30 % presented high levels of sedentary lifestyle and 27 % low self-esteem. These information indicate the importance of generating intervention options is demonstrated in the different levels of education with the aim of palliate the results of this research, working as a team with government organization in the country.

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

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

Recovery in volleyball.

INTRODUCTION: In current team sports (including volleyball), the players have to play numerous competitive matches without time to recover. Volleyball can be defined as a moderate duration exercise including repeated bouts of high-intensity activity interspersed with brief periods of low to moderate active recovery or passive rest. A match is characterized by repeated explosive activities, such as: jumps, shuffles and rapid changes in direction. EVIDENCE ACQUISITION: To guarantee adequate recovery after matches, it is necessary to know the type of fatigue induced and if possible its underlying mechanisms. Recovery strategies are commonly utilized in volleyball despite limited scientific confirmation to support their effectiveness to facilitating optimal recovery. EVIDENCE SYNTHESIS: It is particularly important to optimize recovery because players spend a much greater proportion of their time recovering than they do in training. CONCLUSIONS: Therefore, the main aim of this brief review is to facilitate useful information for practical application, based on the scientific evidence and applied knowledge specifically in volleyball.

Bench press performance during an intermittent hypoxic resistance training to muscle failure.

BACKGROUND: Resistance training performed under hypoxia conditions has been shown to cause major metabolic and hormonal responses. However, the influence of hypoxia on an acute session has been barely studied. The aim of this study was to evaluate the acute effects of an intermittent hypoxic resistance training (IHRT) to muscle failure on bench press performance. METHODS: A randomized crossover design was performed, and 25 untrained men performed a resistance training under two different conditions: normoxia (FIO2=21%) and high-level hypoxia (FIO2=13%). Resistance training consisted of 3 sets of 75% 1RM to muscle failure, with a 2-minute rest between sets. Physical performance was assessed by quantifying total repetitions, concentric velocity and power variable during all sets. Arterial oxygen saturation, heart rate, rating of perceived exertion (RPE), capillary blood lactate and muscle soreness were also assessed after training. RESULTS: Physical performance during bench press did not differ under hypoxic conditions (P>0.05). However, there were significant increases (P<0.05) of RPE (from 7.5±0.8 to 7.9±0.8) and blood lactate concentrations (from 5.5±1.2 to 6.2±1.5 mmol/L) in the hypoxia group. CONCLUSIONS: These findings suggest that hypoxic resistance exercise does not affect exercise performance during bench press exercise. However, influence to perceived exercise intensity and blood lactate concentrations, suggesting that hypoxic resistance training may add substantially to the training dose experienced.