Muscle Oxygen Extraction during Vascular Occlusion Test in Physically Very Active versus Inactive Healthy Men: A Comparative Study.

An increase in the delivery and use of oxygen to the musculature in physically active subjects are determinants of improving health-related aerobic capacity. Additional health benefits, such as an increase in the muscle mass and a decrease in fat mass, principally in the legs, could be achieved with weekly global physical activity levels of more than 300 min. The objective was to compare the muscle vascular and metabolic profiles of physically very active and inactive subjects. Twenty healthy men participated in the study; ten were assigned to the physically very active group (25.5 ± 4.2 years; 72.7 ± 8.1 kg; 173.7 ± 7.6 cm) and ten to the physically inactive group (30.0 ± 7.4 years; 74.9 ± 11.8 kg; 173.0 ± 6.4 cm). The level of physical activity was determined by the Global Physical Activity Questionnaire (GPAQ). A resting vascular occlusion test (5 min of an ischemic phase and 3 min of a reperfusion phase) was used, whereas a near-field infrared spectroscopy (NIRS) device was used to evaluate the muscle oxygenation in the right vastus lateralis of the quadriceps muscle. The area under the curve of the deoxyhemoglobin (HHb) during the ischemic phase and above the curve of the tissue saturation index (TSI) during the reperfusion phase were obtained to determine muscle metabolic and vascular responses, respectively. Physically very active group showed a higher absolute HHb (3331.9 ± 995.7 vs. 6182.7 ± 1632.5 mmol/s) and lower TSI (7615.0 ± 1111.9 vs. 5420.0 ± 781.4 %/s) and relative to body weight (46.3 ± 14.6 vs. 84.4 ± 27.1 mmol/s/kg and 106.0 ± 20.6 vs. 73.6 ± 13.8 %/s/kg, respectively), muscle mass (369.9 ± 122.2 vs. 707.5 ± 225.8 mmol/kg and 829.7 ± 163.4 vs. 611.9 ± 154.2 %/s/kg) and fat mass (1760.8 ± 522.9 vs. 2981.0 ± 1239.9 mmol/s/kg and 4160.0 ± 1257.3 vs. ±2638.4 ± 994.3 %/s/kg, respectively) than physically inactive subjects. A negative correlation was observed between HHb levels and TSI (r = -0.6; p < 0.05). Physically very active men (>300 min/week) present better muscle oxidative metabolism and perfusion and perform significantly more physical activity than physically inactive subjects. Extra benefits for vascular health and muscle oxidative metabolism are achieved when a subject becomes physically very active, as recommended by the World Health Organization. In addition, a higher level of physical activity determined by GPAQ is related to better vascular function and oxidative metabolism of the main locomotor musculature, i.e., the quadriceps.

Effects of Modified Invasion Games on Motor Competence and Self-Assessed Physical Condition in Elementary School Students in the Physical Education Classroom.

Modified invasion games promote the development of real and perceived motor competence. Children with higher motor competence are more likely to participate in physical activity practice and to remain in it, both in adolescence and adulthood. (1) Background: The purpose of this study is to determine the effect of modified invasion games on the real motor competence and self-assessment of the physical condition fifth-grade students from a private school in Viña del Mar, Chile. (2) Methods: 40 girls and boys with an average age of 11.47 years (SD = 0.554) participated in this study during a 12-week intervention. The MOBAK 5-6 battery was used to assess actual motor competence, the SEMOK questionnaire was used to determine perceived motor competence, the International Fitness Scale (IFIS) self-assessment questionnaire was used to assess perceived physical fitness, and the weight/size ratio was used to determine BMI. A Friedman's nonparametric ANOVA analysis was applied to determine the effect of the intervention, in addition to an analysis of covariance (ANCOVA) to identify the influence of the covariates on motor competence. (3) Results: No statistically significant differences were established between weight, BMI, and waist circumference. There was a statistically significant difference after the intervention in the actual motor competence of object control (p = 0.005) and perceived motor competence of object control (p ≤ 0.001) (4) Conclusions: An intervention based on modified invasion games is effective for the improvement of actual and perceived motor competence of object control. It was not possible to identify a positive effect on the self-assessment of muscle strength after the intervention.

Análisis de Datos Antropométricos y Madurativos para la Selección de Talentos en Voleibol / Analysis of Anthropometric and Maturational Data for Talents Selection in Volleyball

El proceso madurativo tiene una gran influencia sobre los factores antropométricos y las capacidades físicas del atleta, y por tanto, sobre el proceso de selección de talentos deportivos. El objetivo de este trabajo fue analizar el estado madurativo y las características antropométricas junto con la comparación de estos datos por sexo en una muestra de 39 jugadores jóvenes de voleibol dentro de un proceso de selección de talentos (19 damas de 14,88±1,05 años y 13 varones de 15,1 años). Se obtuvieron datos de edad cronológica, altura, peso, altura sentado, altura de la madre y padre, la edad pico de crecimiento, el "timing" o periodo de tiempo por encima o por debajo de la edad pico, altura al final del proceso madurativo, el porcentaje actual de altura máxima, los centímetros restantes y el estado madurativo (pre-púber, púber o pos-púber). Los jugadores mostraron una mayor altura en el momento de las mediciones (179,92±6,87 vs 171,05±4,80; p<0,001), así como una mayor altura final calculada (189,46±3,73 vs 178,52±5,17; p<0,001), en comparación a las jugadoras. El pico en la velocidad de crecimiento también fue superior en los jugadores (14,56±0,44 vs 12,60±0,57; p<0,001), aunque su timing era inferior al de las jugadoras (0,531±1,19 vs 2,27±0,64; p<0,001). Esto se debió a un mayor porcentaje de jugadores masculinos en estados puberales, incluyendo un jugador en estadio pre-puberal, mientras que fue abundante la presencia de jugadoras en estado pospuberal. Estos datos reflejan la gran cantidad de jugadores que tienden a estar en periodos avanzados de maduración en procesos de selección de talentos. Por tanto, entrenadores y seleccionadores deben contemplar estas variables para evitar sesgos en el proceso de identificación del talento deportivo.

SUMMARY: The maturation process has a great influence on the anthropometric factors and physical capabilities of the athlete, and therefore, on the selection process of sporting talents. The objective of this work was to analyze the maturational state and anthropometric characteristics together with the comparison of these data by sex in a sample of 39 young volleyball players within a talent selection process (19 ladies of 14.88±1. 05 years old and 13 males aged 15.1 years). Data were obtained on chronological age, height, weight, sitting height, height of the mother and father, peak age of growth, timing or period of time above or below the peak age, height at the end of the process. maturation, the current percentage of maximum height, the remaining centimeters and the maturation status (pre-pubertal, pubertal or post-pubertal). The players showed a greater height at the time of the measurements (179.92±6.87 vs. 171.05±4.80; p<0.001), as well as a greater final calculated height (189.46±3.73 vs. 178.52±5.17; p<0.001), compared to the female players. The peak in growth speed was also higher in male players (14.56±0.44 vs 12.60±0.57; p<0.001), although their timing was lower than that of female players (0.531±1.19 vs 2.27±0.64; p<0.001). This was due to a higher percentage of male players in pubertal states, including one player in a pre-pubertal stage, while the presence of female players in a post-pubertal stage was abundant. These data reflect the large number of players who tend to be in advanced periods of maturation in talent selection processes. Therefore, coaches and selectors must consider these variables to avoid biases in the process of identifying sporting talent.

Association between Fractional Oxygen Extraction from Resting Quadriceps Muscle and Body Composition in Healthy Men.

This study aimed to associate body composition with fractional oxygen extraction at rest in healthy adult men. Fourteen healthy adults (26.93 ± 2.49 years) from Chile participated. Body composition was assessed with octopole bioimpedance, and resting muscle oxygenation was evaluated in the vastus lateralis quadriceps with near-infrared spectroscopy (NIRS) during a vascular occlusion test, analyzing the muscleVO2, resaturation velocity during reactive hyperemia via the muscle saturation index (%TSI), and the area above the curve of HHb (AACrep). It was observed that the total and segmented fat mass are associated with lower reoxygenation velocities during hyperemia (p = 0.008; ß = 0.678: p = 0.002; ß = 0.751), and that the total and segmented skeletal muscle mass are associated with higher reoxygenation velocities during hyperemia (p = 0.020; ß = -0.614: p = 0.027; ß = -0.587). It was also observed that the total and segmented fat mass were associated with a higher area above the curve of HHb (AACrep) during hyperemia (p = 0.007; ß = 0.692: p = 0.037; ß = 0.564), and that total and segmented skeletal muscle mass was associated with a lower area above the curve of HHb (AACrep) during hyperemia (p = 0.007; ß = -0.703: p = 0.017; ß = -0.632). We concluded that fat mass is associated with lower resaturation rates and lower resting fractional O2 extraction levels. In contrast, skeletal muscle mass is associated with higher resaturation rates and fractional O2 extraction during reactive hyperemia. The AACrep may be relevant in the evaluation of vascular adaptations to exercise and metabolic health.

Relación entre la Composición Corporal, Condición Física y Capacidad Operativa en Militares Chilenos / Relationship Between Body Composition, Physical Condition and Operational Capacity in Chilean Military

La composición corporal engloba una serie de variables relacionadas con la salud e influye en la condición física. A pesar de ello, existe poca evidencia sobre sus efectos en la capacidad operativa en militares. El objetivo de este estudio fue relacionar la composición corporal, la condición física y la capacidad operativa de militares chilenos. Participaron 57 militares chilenos (26,9 ± 4,8 años), con especialización operativa en infantería. La composición corporal fue evaluada con bioimpedancia octopolar estimando masa libre de grasa, tejido muscular y tejido adiposo, entre otras variables. También se realizaron las siguientes pruebas de condición física: 5000 m planos, dominadas, abdominales y flexibilidad, así como cuatro pruebas específicas de actividades operativas militares específicas (situación de combate simulado). Los resultados mostraron un porcentaje de tejido muscular de 45,4 ± 2,9 % (IC95%: 44,6 - 46,2), mientras que el porcentaje de tejido adiposo fue de 20,3 ± 4,9 % (IC95%: 14,7 - 17,3). Se encontraron correlaciones negativas de pequeña magnitud entre el tiempo de carrera (5000 m) y el tejido muscular (%) (r = -0,275) y positiva con el tejido adiposo (%) (r = 0,294). Sin embargo, se observaron correlaciones de alta magnitud entre dominadas y tejido muscular (%) (r = 0,517) y tejido adiposo (%) (r = -0,558). El tejido adiposo se relacionó negativamente con la capacidad aeróbica, fuerza de brazos(??) y fuerza resistencia abdominal, mientras que el tejido muscular se relacionó positivamente con estas mismas variables. No se apreciaron correlaciones entre la composición corporal y la capacidad operativa militar (p<0,05). Se concluye que la composición corporal y la condición física no se relacionan con la capacidad operativa militar en situación de combate en especialistas en infantería, pero si la composición corporal se relaciona con la fuerza y la capacidad cardiorrespiratoria.

SUMMARY: Body composition encompasses a series of variables that are health-related and influence physical condition. Nevertheless, there is little evidence on its effects on the operational capacity of the military. The objective of this study was to relate the body composition, the physical condition and the operational capacity of the Chilean military. Fifty-seven Chilean soldiers (26.9 ± 4.8 years) participated, with operational specialization in infantry. Body composition was evaluated with octopolar bioimpedance, estimating fat- free mass, muscle tissue, and adipose tissue, among other variables. The following physical condition tests were also carried out: 5000 m flat, pull-ups, abdominals and flexibility, as well as four specific tests of specific military operational activities (simulated combat situation). The results showed a percentage of muscle tissue of 45.4 ± 2.9 % (95%CI: 44.6 - 46.2), while the percentage of adipose tissue was 20.3 ± 4.9 % (95%CI). : 14.7-17.3). Negative correlations of small magnitude were found between race time (5000 m) and muscle tissue (%) (r = -0.275) and positive with adipose tissue (%) (r = 0.294). However, high magnitude correlations were observed between pull-ups and muscle tissue (%) (r = 0.517) and adipose tissue (%) (r = -0.558). Adipose tissue was negatively related to aerobic capacity, arm strength, and abdominal endurance strength, while muscle tissue was positively related to these same variables. No correlations were found between body composition and military operational capacity (p<0.05). It is concluded that body composition and physical condition are not related to military operational capacity in combat situations in infantry specialists, but body composition is related to strength and cardiorespiratory capacity.

[Profile and indicators of long-stay establishments for older adults in Chile]. / Perfil e indicadores de los establecimientos de larga estancia para adulto mayor en Chile.

BACKGROUND AND OBJECTIVE: In this article we sought to characterize the Long Stay Establishments for the Elderly in Chile, besides presenting the services offered in the public and private. MATERIAL AND METHODS: It is a quantitative, cross-sectional descriptive study, with secondary information source. We analyze all establishments in the country registered with the National Service of the Elderly. As of November 2015, a total of 724 establishments were registered and distributed in 169 neighborhoods throughout the country in which 16,985 adults aged 60 and over were institutionalized. RESULTS: Most of the establishments (65.9% [n=246/724]) are private, 47.5% of them (n=344/724) are located in the metropolitan region of Santiago. Of the residents' health, only 26.5% are considered functional brave, 28.3% are physically handicapped and 8.8% are mentally handicapped. Most establishments offer manual activities, physical exercises, memory classes, cultural classes and recreational or touristic tours. Proportionally of the activities offered were mostly private ones. CONCLUSIONS: In Chile, most of the establishments are private, located in the metropolitan region where there is the largest supply deficit of this type of service, with an occupancy rate of 90.7%, with 72.4% women and almost half 47.7% with some physical or psychic dependence.

Perfil e indicadores de los establecimientos de larga estancia para adulto mayor en Chile / Profile and indicators of long-stay establishments for older adults in Chile

Antecedentes y objetivo: En este artículo sé buscó caracterizar los establecimientos de larga estancia para adultos mayores (ELEAM) de Chile, además de presentar los servicios ofrecidos en lo público y en lo privado. Material y métodos: Se trata de un estudio cuantitativo, transversal descriptivo, a través de fuente de información secundaria. Analizamos todos los ELEAM del país registrados en el Servicio Nacional del Adulto Mayor (SENAMA). Hasta noviembre de 2015 un total de 724 ELEAM estaban registrados y distribuidos en 169 comunas alrededor del país, en los cuales estaban institucionalizados 16.985 adultos con edad a partir de los 60años. Resultados: La mayoría de los ELEAM (65,9% [n=344/724]) son privados. Entre ellos, el 47,5% (n=246/724) están localizados en la región metropolitana de Santiago. De la salud de los residentes, apenas el 26,5% son considerados autosuficientes funcionales, el 28,3% son deficientes físicos y el 8,8%, deficientes psíquicos. La mayoría de los establecimientos ofrecen actividades manuales, ejercicios físicos, clases de memoria, clases culturales y paseos recreativos o turísticos. Proporcionalmente, la mayoría de las actividades ofrecidas eran privadas. Conclusiones: En Chile la mayor parte de los establecimientos son de carácter privado, ubicados en la región metropolitana, donde se encuentra un mayor déficit de oferta de este servicio, con una tasa de ocupación del 90,7%, siendo el 72,4% mujeres, y casi la mitad (47,7%) con alguna dependencia física o psíquica. (AU)

Background and objective: In this article we sought to characterize the Long Stay Establishments for the Elderly in Chile, besides presenting the services offered in the public and private. Material and methods: It is a quantitative, cross-sectional descriptive study, with secondary information source. We analyze all establishments in the country registered with the National Service of the Elderly. As of November 2015, a total of 724 establishments were registered and distributed in 169 neighborhoods throughout the country in which 16,985 adults aged 60 and over were institutionalized. Results: Most of the establishments (65.9% [n=246/724]) are private, 47.5% of them (n=344/724) are located in the metropolitan region of Santiago. Of the residents’ health, only 26.5% are considered functional brave, 28.3% are physically handicapped and 8.8% are mentally handicapped. Most establishments offer manual activities, physical exercises, memory classes, cultural classes and recreational or touristic tours. Proportionally of the activities offered were mostly private ones. Conclusions: In Chile, most of the establishments are private, located in the metropolitan region where there is the largest supply deficit of this type of service, with an occupancy rate of 90.7%, with 72.4% women and almost half 47.7% with some physical or psychic dependence. (AU)

Physical fitness mediates the inverse association between fatness indicators and academic achievement, despite the school vulnerability of adolescents-The Cogni-Action Project.

Objective: This study aims to determine the mediating role of physical fitness in the relationship between fatness indicators and academic achievement, exploring the influence of school vulnerability. Methods: A total of 1,296 Chilean adolescents (aged 10 to 14 years; 50% girls) participated in this study. The global fitness score (GFS) was obtained by adding the three main components of the ALPHA fitness test: cardiorespiratory fitness (CRF), muscular fitness (MF), and speed/agility fitness (SAF). CRF was evaluated through the 20 m shuttle run test; MF by upper and lower limb strength tests; and SAF by the 4 × 10 shuttle run test. BMIz and WHtR were evaluated as general (unspecific) and central (specific) fatness indicators. Academic achievement was established through grades in math, language, and science and their average scores. Multiple mediation analyses were performed according to two models, adjusted for sex, maturity, and schools (model 1), and in model 2, the school vulnerability index (SVI) was added. The SVI is an important proxy of socioeconomic status at the school level, and it was categorized as high-, mid-, or low-SVI. Mediation percentages were calculated, and confidence intervals (bootstrapping) were used to establish significant findings. Results: CRF, SAF, and GFS mediate the relationship between fatness indicators and academic achievement, both partially and totally (ranging from 12.7 to 59.2%). However, MF did not show any mediation effect. After controlling for SVI, CRF, and GFS, mediation changed from partial to total in the associations between math and science with WHtR. Although SAF contributed to GFS mediation, CRF seems to have the most significant mediation role for all academic achievements, regardless of SVI and the fat indicator studied. Conclusion: A higher level of general physical fitness, especially CRF, significantly mediates the detrimental influence of fatness on the academic achievement of schoolchildren. This study suggests that physical fitness plays a relevant role in academic and public health, considering the high prevalence and detrimental influence of obesity and school vulnerability in children and adolescents.

Which one? A comparative study of traditional and sports uniforms on academic achievement, cognitive performance, playtime, bullying, and discrimination in adolescents: The Cogni-Action Project.

Objective: The aim of this study was to compare academic achievement, cognitive performance, playtime, bullying, and discrimination in adolescents according to traditional uniforms (TUs) and sports uniforms (SUs) worn at school, while simultaneously exploring the influence of the school vulnerability index. Methods: A total of 988 Chilean adolescents (52.6% boys) aged 10-14 years participated in this cross-sectional study. Academic achievement was evaluated by the average grade in maths, language, and science grades, while cognitive performance was assessed through eight cognitive tasks. TUs affecting physical activity, playtime, bullying, and discrimination were queried. Mixed model analyses were performed. Results: No differences were observed in academic achievement (TU: 5.4 ± 0.1 vs. SU: 5.5 ± 0.2, p = 0.785) or in cognitive performance (TU: 99.6 ± 0.8 vs. SU: 98.9 ± 1.8, p= 0.754) according to the school uniformtype. Moreover, 64.1 % of participants declared that wearing TU affects their physical activity (traditional uniforms: + 8 min and sports uniforms: + 20 min), and those who believed so spent more time playing than those who answered negatively (14.5 min, p = 0.012). Finally, adolescents wearing SU displayed a lower feeling of bullying and discrimination; this finding depended mainly on the school's vulnerability. Conclusion: It is concluded that wearing TU does not show an educational advantage at an academic and cognitive level that justifies its obligation. In addition, it could be suggested that schools consider adolescents' opinions in adopting a more comfortable uniform, such as the SU. This feasible and low-cost measure would help to increase adolescents' physical activity during the school day, and, contrary to belief, it would not be related to increased feelings of bullying and discrimination.

Perfil de composición corporal en militares élite chilenos / Body composition profile of elite Chilean military

RESUMEN: La Bioimpedancia Eléctrica (BIA), al ser una técnica no invasiva pero de elevada precisión, se ha convertido en la actualidad en una herramienta valiosa para determinar la composición corporal en militares, facilitado el control de las distintas variables que se asocian a cada especialidad. El objetivo del presente estudio fue describir el perfil de composición corporal en militares de elite al momento de finalizar un curso de especialización. Participaron 11 militares con un rango de edad entre 22 y 29 años. Se evalúo la composición corporal a través de BIA, inmediatamente después de finalizado un curso de especialización para militares de élite. Las evaluaciones en los militares sobre las variables de la composición corporal a través de BIA mostraron: peso corporal de 84,3 ± 4,52 kg, talla 1,78 ± 0,06 m, índice de masa corporal (IMC) 26,5 ± 1,09, tejido adiposo de 13,7 ± 3,65 %, tejido muscular 49,5 ± 2,34 %, masa libre de grasa 72,7 ± 5,23 kg y 53,2 ± 3,78 l de agua corporal total. Conclusiones: Los militares de elite presentaron elevados niveles de masa libre de grasa, tejido muscular y bajos niveles de tejido adiposo lo que favorece el desarrollo de las actividades militares especializadas y disminuye el riesgo de lesiones. Los datos aquí recogidos sirven como marco de referencia para futuros estudios.

SUMMARY: Electrical bioimpedance (BIA), being a non- invasive technique but with high precision, has become a valuable tool for determining body composition in the military, facilitating the control of the different variables associated with each specialty. The aim of the present study was to describe the body composition profile of elite military personnel at the end of a specialization course. Eleven military personnel between 22 and 29 years of age participated in the study. Body composition was assessed by BIA immediately after completion of a specialization course for elite military personnel. Assessments in the military on body composition variables through BIA showed: body weight of 84.3 ± 4.52 kg, height 1.78 ± 0.06 m, body mass index (BMI) 26.5 ± 1.09, adipose tissue of 13.7 ± 3.65 %, muscle tissue 49.5 ± 2.34 %, fat free mass 72.7 ± 5.23 kg and 53.2 ± 3.78 l of total body water. Conclusions: Elite military personnel presented high levels of fat free mass, muscle tissue and low levels of adipose tissue which favors the development of specialized military activities and decreases the risk of injury. The data collected here serve as a frame of reference for future studies.

Effects of a concurrent training protocol on body composition and phase angle in physically inactive young women: a quasi-experimental intervention study / Efectos de un protocolo de entrenamiento concurrente sobre la composición corporal y el ángulo de fase en mujeres jóvenes físicamente inactivas: un estudio de intervención cuasi-experimental

SUMMARY: To determine the effect of a concurrent training program on body composition and phase angle in young women. 38 women (19.26 ± 1.86 years) participated in the study, and were assigned according to convenience sampling into two groups: 11 into the control group (CG) and 27 into the intervention group (IG). The IG performed a 12-weeks concurrent training protocol. The frequency was five days a week, and the intensity was established in 40-60 % of a repetition maximum to strength exercise, and 40-65 % heart rate reserve to endurance exercise. Body composition and phase angle were evaluated by bioelectrical impedance before and after the intervention. The IG had a decrease in fat mass (pre = 24.66 ± 5.65 kg; post = 20.38 ± 4.20 kg; Cohen's d = .80; p< 0,001 [CI 95 % = 3.34,5.22]), and an increase in muscle mass (pre = 22.75 ± 3.23 kg; post: 23.50 ± 3.41 kg; Cohen's d = -0.86; p= <0,001[CI 95 % = -1.09,- 0.40]) and total phase angle (pre = 5.72º ±0.39; post: 6.24º ± 0.51; Cohen's d = -1.32; p=<0,001 [CI 95 % = -0.67,-0.36]), whereas the CG had not show significant variations in variables of body composition or total phase angle. The results suggest that a 12-weeks concurrent training program could modify positively the young women's body composition and phase angle. Hence, it is recommended using similar protocols to change variables related to young women's health.

RESUMEN: El objetivo fue determinar el efecto de un programa de entrenamiento concurrente sobre la composición corporal y el ángulo de fase en mujeres jóvenes. 38 mujeres (19.26 ± 1.86 años) participaron en el estudio, y fueron asignadas de acuerdo a un muestreo de conveniencia en dos grupos: 11 en el grupo control (CG) y 27 en el grupo de intervención (GI). El IG realizó un protocolo de entrenamiento concurrente de 12 semanas. La frecuencia fue de cinco días a la semana y la intensidad se estableció en 40-60 % una repetición máxima para el ejercicio de fuerza y 40-65 % de frecuencia cardíaca de reserva para ejercicio de resistencia. La composición corporal y el ángulo de fase se evaluaron mediante impedancia bioeléctrica antes y después de la intervención. El IG tuvo una disminución en la masa grasa (pre = 24.66 ± 5.65 kg; post = 20.38 ± 4.20 kg; d de Cohen = .80; p <0,001 [IC 95 % = 3.34,5.22]), y un aumento en la masa muscular (pre = 22,75 ± 3,23 kg; post: 23,50 ± 3,41 kg; d de Cohen = -0,86; p = <0,001 [IC 95 % = -1,09, -0,40]) y ángulo de fase total (pre = 5,72º ± 0,39; post: 6,24 º ± 0,51; d de Cohen = -1,32; p = <0,001 [IC 95 % = -0,67, -0,36]), mientras que el GC no mostró variaciones significativas en las variables de composición corporal o ángulo de fase total. Los resultados sugieren que un programa de entrenamiento concurrente de 12 semanas podría modificar positivamente la composición corporal y el ángulo de fase de mujeres jóvenes. Por lo tanto, se recomienda utilizar protocolos similares para mofificar variables relacionadas con la salud de mujeres jóvenes.

Composición corporal, parámetros bioeléctricos y fuerza de prensión manual en escaladores chilenos federados y recreativos / Body composition, bioelectrical parameters, and handgrip strength in federated and recreational Chilean climbers

RESUMEN: El objetivo del siguiente estudio fue determinar y comparar los valores de composición corporal, parámetros bioeléctricos y fuerza de prensión manual de escaladores chilenos federados y recreativos. Participaron voluntariamente 13 escaladores chilenos, de los cuales 4 eran federados (25,75 ± 2,87 años) y 9 recreativos (22,33 ± 1,41 años). La composición corporal se evaluó por medio de un impedanciómetro bioeléctrico octopolar multifrecuencia, mientras que la fuerza de prensión manual se determinó con un dinamómetro manual. Si bien no hubo diferencias en las variables de composición corporal entre ambos grupos, el ángulo de fase del tronco fue superior en los federados en comparación a los recreativos (p = 0,011 [95 % IC = 1,10; 5,20]). Respecto a la fuerza de prensión manual, la fuerza relativa fue superior para los federados (p = 0,025 [95 % IC = 0,10; 0,22]), mientras que la diferencia de la fuerza entre la mano dominante y no dominante fue mayor para los recreativos (p = 0,012 [95 % IC = 1,60; 10,05]). Este es uno de los primeros estudios que explora las diferencias entre escaladores chilenos federados y recreativos. Los resultados sugieren una diferenciación a nivel de ángulo de fase y fuerza de prensión manual, lo cual debería corroborarse con futuros estudios.

SUMMARY: This study aimed to determine and compare the body composition, bioelectric parameters, and handgrip strength in federated and recreational Chilean climbers. Thirteen Chilean climbers voluntarily participated, being 4 federated (25.75 ± 2.87 years) and 9 recreational (22.33 ± 1.41 years). Body composition was measured using a multifrequency octopolar bioelectrical impedance meter, while handgrip strength was determined with a dynamometer. Although there were no statistical differences in the body composition variables between groups, the trunk phase angle was statistically higher in the federated compared to the recreational climbers (p = 0,011 [95 % CI = 1,10; 5,20]). Regarding handgrip strength, the relative strength was higher for federated (p = 0,025 [95 % CI = 0,10; 0,22]), while the difference in strength between dominant and non-dominant hand was higher for recreational climbers (p = 0,012 [95 % CI = 1,60; 10,05]). This study is one of the first that explore the differences between federated and recreational Chilean climbers. These results suggest a differentiation at the level of phase angle and handgrip strength, which should be corroborated in future studies.

Características de composición corporal, ángulo de fase y agua corporal en paracaidistas chilenos de elite / Characteristics of body composition, phase angle and body water in elite Chilean skydivers

RESUMEN: Durante la práctica del paracaidismo, una deficiente composición corporal no sólo puede afectar el rendimiento deportivo, sino que, además, incrementa la probabilidad de sufrir una lesión o accidente grave. Conocer las características de sus componentes, podría ayudar a prevenirlas. El objetivo del estudio fue describir la composición corporal, ángulos de fase y agua corporal total en paracaidistas chilenos de alta competencia. Participaron del estudio 8 paracaidistas profesionales del Team Chile® (33,4 ± 4,9 años) con más de seis años de experiencia. La evaluación de las masas grasa, muscular, libre de grasa, magra y visceral, así como el ángulo de fase y el agua corporal total obtenida a través de impedancia bioeléctrica. Los deportistas presentaron un peso corporal de 76,7 ± 5,7 kg, estatura 1,72 ± 0,1 m e IMC 26,0 ± 1,9 kg/m2. La composición corporal promedio mostró un 20,6 ± 3,0 % de masa grasa, 44,9 ± 2,0 % de masa muscular y 79,4 ± 3,0 % de masa libre de grasa. El ángulo de fase promedio fue de 7,25 ± 0,33°. El agua corporal total de los participantes fue de 44,6 ± 3,2 1. Se concluye que los resultados obtenidos pueden ser utilizados por los profesionales de las ciencias del deporte como valores de referencia para el control de la composición corporal, fase angular y agua corporal en paracaidistas para optimizar el rendimiento deportivo y evitar lesiones.

SUMMARY: Unsuitable body composition in skydivers not only affect the sport performance but also could increase the probability of risk injury or severe accident; hence, to determine body composition characteristics could be helpful to prevent such events. This study aimed to describe body composition, phase angle, and total body water in highly trained Chilean skydivers. Eight Team Chile® professional skydivers (33.4 ± 4.9 years) with more than 6 years of experience participated in this study. Fat mass, muscle mass, fat-free mass, lean mass, visceral mass, phase angle, and total body water were measured by bioelectrical impedance. Skydivers had a bodyweight of 76.7±5.7 kg, a height of 1.72 ±0.1 m, and a body mass index of 26.0 ±1.9 kg/m2. Regarding body composition, they had a fat mass of 20.6 ±3.0 %, a muscle mass of 44.9 ±2.0 %, and a fat-free mass of 79.4 ±3.0 %. Phase angle and total body water were 7.25 ±0.3° and 344.6±3.2, respectively. The present findings could be useful to science sport professionals as reference values of body composition, phase angle, and total body water of highly trained skydivers to improve sports performance and avoid injuries.

Impact of Exercise on Gut Microbiota in Obesity.

Physical activity, exercise, or physical fitness are being studied as helpful nonpharmacological therapies to reduce signaling pathways related to inflammation. Studies describing changes in intestinal microbiota have stated that physical activity could increase the microbial variance and enhance the ratio of Firmicutes/Bacteroidetes, and both actions could neutralize the obesity progression and diminish body weight. The aim of this review is to provide an overview of the literature describing the relationship between physical activity profiles and gut microbiota and in obesity and some associated comorbidities. Promoting physical activity could support as a treatment to maintain the gut microbiota composition or to restore the balance toward an improvement of dysbiosis in obesity; however, these mechanisms need to be studied in more detail. The opportunity to control the microbiota by physical activity to improve health results and decrease obesity and related comorbidities is very attractive. Nevertheless, several incompletely answered questions need to be addressed before this strategy can be implemented.

Physical fitness and its association with cognitive performance in Chilean schoolchildren: The Cogni-Action Project.

This study aimed to establish the association and differences in a diversity of cognitive domains according to cardiorespiratory fitness (CRF), muscular fitness (MF), and speed-agility fitness (S-AF) level in a large sample of Chilean schoolchildren. 1171 Chilean schoolchildren aged 10-14 years participated. CRF, MF, and S-AF were assessed through the ALPHA-fitness test battery. Cognition was evaluated through the NeuroCognitive Performance Test, which involved eight tests related to four main domains: cognitive flexibility (CF), working memory (WM), inhibitory control (IC), and intelligence (IN). Both global (multivariate) and individual (univariate) analyses were performed to determine the differences in cognitive functioning according to low-, middle-, and high-fitness level. The global analyses showed a significant main effect for CRF, F(16,940)  = 3.08, p ≤ .001 and MF groups, F(16,953)  = 2.30, p = .002, but not for S-AF, F(16,948)  = 1.37, p = .105. CRF shows a significant main effect in seven of eight tests, involving CF, WM, IC, and IN domains, whereas MF shows a significant main effect in five of eight tests without association with IN. SA-F shows a significant main effect only with IC. Statistical differences were found between the low- and middle/high-fitness groups but not between the middle- and high-fitness groups. At a global level, both CRF and MF seem to be associated with a higher cognitive profile in scholars; however, at an individual level, all fitness components show a favorable relationship to some cognitive domine. Then, future cognitive developing strategies should consider all fitness components, prioritizing those low-fitness schoolchildren.

Insights into the Impact of Microbiota in the Treatment of NAFLD/NASH and Its Potential as a Biomarker for Prognosis and Diagnosis.

Non-alcoholic fatty liver disease (NAFLD) is an increasing cause of chronic liver illness associated with obesity and metabolic disorders, such as hypertension, dyslipidemia, or type 2 diabetes mellitus. A more severe type of NAFLD, non-alcoholic steatohepatitis (NASH), is considered an ongoing global health threat and dramatically increases the risks of cirrhosis, liver failure, and hepatocellular carcinoma. Several reports have demonstrated that liver steatosis is associated with the elevation of certain clinical and biochemical markers but with low predictive potential. In addition, current imaging methods are inaccurate and inadequate for quantification of liver steatosis and do not distinguish clearly between the microvesicular and the macrovesicular types. On the other hand, an unhealthy status usually presents an altered gut microbiota, associated with the loss of its functions. Indeed, NAFLD pathophysiology has been linked to lower microbial diversity and a weakened intestinal barrier, exposing the host to bacterial components and stimulating pathways of immune defense and inflammation via toll-like receptor signaling. Moreover, this activation of inflammation in hepatocytes induces progression from simple steatosis to NASH. In the present review, we aim to: (a) summarize studies on both human and animals addressed to determine the impact of alterations in gut microbiota in NASH; (b) evaluate the potential role of such alterations as biomarkers for prognosis and diagnosis of this disorder; and (c) discuss the involvement of microbiota in the current treatment for NAFLD/NASH (i.e., bariatric surgery, physical exercise and lifestyle, diet, probiotics and prebiotics, and fecal microbiota transplantation).

The Gut Barrier, Intestinal Microbiota, and Liver Disease: Molecular Mechanisms and Strategies to Manage.

Liver disease encompasses pathologies as non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, alcohol liver disease, hepatocellular carcinoma, viral hepatitis, and autoimmune hepatitis. Nowadays, underlying mechanisms associating gut permeability and liver disease development are not well understood, although evidence points to the involvement of intestinal microbiota and their metabolites. Animal studies have shown alterations in Toll-like receptor signaling related to the leaky gut syndrome by the action of bacterial lipopolysaccharide. In humans, modifications of the intestinal microbiota in intestinal permeability have also been related to liver disease. Some of these changes were observed in bacterial species belonging Roseburia, Streptococcus, and Rothia. Currently, numerous strategies to treat liver disease are being assessed. This review summarizes and discusses studies addressed to determine mechanisms associated with the microbiota able to alter the intestinal barrier complementing the progress and advancement of liver disease, as well as the main strategies under development to manage these pathologies. We highlight those approaches that have shown improvement in intestinal microbiota and barrier function, namely lifestyle changes (diet and physical activity) and probiotics intervention. Nevertheless, knowledge about how such modifications are beneficial is still limited and specific mechanisms involved are not clear. Thus, further in-vitro, animal, and human studies are needed.

The Mediation Effect of Self-Report Physical Activity Patterns in the Relationship between Educational Level and Cognitive Impairment in Elderly: A Cross-Sectional Analysis of Chilean Health National Survey 2016-2017.

The aims of this cross-sectional study were (i) to determine the association of educational level attained with cognitive impairment and (ii) to investigate the mediating effect of different self-report physical activity (PA) patterns in a large sample of older Chileans. A sample of 1571 older adults from the National Chilean Survey (2016-2017) was included. The educational level attained, PA levels, mode of commuting, sedentary time, and leisure-time PA were self-reported through validated questionnaires. Cognitive impairment was determined by Mini-Mental State Examination (modified version). Association between educational level attained and cognitive impairment was examined using logistic regression models. Counterfactual mediation models were used to test the mediating effect of self-reported PA patterns. A lower educational level was consistently associated with higher odds of cognitive impairment (OR range 2.846 to 2.266, all p < 0.001), while leisure-time PA was the only PA pattern that partially mediated this association (proportion mediated 8.0%). In conclusion, leisure-time PA was the solely PA pattern that partially mediated the association between the educational level and cognitive impairment. The rest self-reported PA patterns did not modify this association.

Study protocol and rationale of the "Cogni-action project" a cross-sectional and randomized controlled trial about physical activity, brain health, cognition, and educational achievement in schoolchildren.

BACKGROUND: Education and health are crucial topics for public policies as both largely determine the future wellbeing of the society. Currently, several studies recognize that physical activity (PA) benefits brain health in children. However, most of these studies have not been carried out in developing countries or lack the transference into the education field. The Cogni-Action Project is divided into two stages, a cross-sectional study and a crossover-randomized trial. The aim of the first part is to establish the associations of PA, sedentarism, and physical fitness with brain structure and function, cognitive performance and academic achievement in Chilean schoolchildren (10-13 years-old). The aim of the second part is to determinate the acute effects of three PA protocols on neuroelectric indices during a working memory and a reading task. METHODS: PA and sedentarism will be self-reported and objectively-assessed with accelerometers in a representative subsample, whilst physical fitness will be evaluated through the ALPHA fitness test battery. Brain structure and function will be assessed by magnetic resonance imaging (MRI) in a randomized subsample. Cognitive performance will be assessed through the NeuroCognitive Performance Test, and academic achievement by school grades. In the second part 32 adolescents (12-13 year-old) will be cross-over randomized to these condition (i) "Moderate-Intensity Continuous Training" (MICT), (ii) "Cooperative High-Intensity Interval Training" (C-HIIT), and (iii) Sedentary condition. Neuroelectric indices will be measures by electroencephalogram (EEG) and eye-tracking, working memory by n-back task and reading comprehension by a reading task. DISCUSSION: The main strength of this project is that, to our knowledge, this is the first study analysing the potential association of PA, sedentarism, and physical fitness on brain structure and function, cognitive performance, and academic achievement in a developing country, which presents an important sociocultural gap. For this purpose, this project will use advanced technologies in neuroimaging (MRI), electrophysiology (EEG), and eye-tracking, as well as objective and quality measurements of several physical and cognitive health outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03894241 Date of register: March 28, 2019. Retrospectively Registered.