A comparison of body composition assessment methods in climbers: Which is better?

OBJECTIVE: To compare body composition estimations of field estimation methods: Durnin & Womersley anthropometry (DW-ANT), bioelectrical impedance analysis (BIA) and Deborah-Kerr anthropometry (DK-ANT) against dual-energy X-ray absorptiometry (DXA) in a male Chilean sport climbing sample. METHODS: 30 adult male climbers of different performance levels participated in the study. A DXA scan (Lunar Prodigy®) was used to determine fat mass, lean mass and total bone mineral content (BMC). Total muscle mass (MM, kg) was estimated through a validated prediction model. DW-ANT and BIA ("non-athletes" and "athletes" equations) were used to determinate fat mass percentage (FM %), while DK-ANT was utilized to estimate MM and BMC. RESULTS: A significant (p<0.01) inter-method difference was observed for all methods analyzed. When compared to DXA, DW-ANT and BIA underestimated FM% and DK-ANT overestimated MM and BMC (All p<0.01). The inter-method differences was lower for DW-ANT. DISCUSSION: We found that body composition estimation in climbers is highly method dependent. If DXA is not available, DW-ANT for FM% has a lower bias of estimation than BIA in young male Chilean climbers. For MM and BMC, further studies are needed to compare and estimate the DK-ANT bias level. For both methods, correction equations for specific climbing population should be considered.

Influence of a self-regulated cognitive dual task on time to failure and complexity of submaximal isometric force control.

PURPOSE: To determine the effects of performing a self-regulated cognitive dual task on time to failure and neuromuscular force control during submaximal isometric contractions. METHODS: Fifteen young sedentary males performed isometric contractions at 50% of each individual's maximal voluntary contraction (MVC) under single-task (without cognitive load) and dual-task (with self-regulated mathematical task) conditions. Force signal complexity and biceps brachialis muscle activity were determined at the start, middle, and end of each trial. The slope of the linear regression of median frequency determined the rate of muscle fatigue. Force-task error was established as any amplitude percentage greater or less than 50% MVC. RESULTS: The dual-task condition resulted in a 42 s longer time to failure than the single-task condition. EMG amplitude did not differ between conditions. The rate of muscle fatigue was higher in the single-task (- 0.35%/s) than the dual-task (- 0.2%/s) condition. Force signal complexity was, on average, 22% lower in the dual-task condition. The dual-task condition, as compared to the single-task condition, elicited a higher rate of force-task error below (6.37 versus 4.76%) and over (2.11 versus 1.68%) the force threshold. CONCLUSION: The dual-task condition resulted in a longer time to failure and decreased motor output complexity and fatigue rate when performing a submaximal force task. As the dual task also increased the force-task error, we suggest cognitive dual tasks as a possible strategy for delaying fatigue in sedentary young males when exerting submaximal isometric force, contributing to neuromuscular training when error in force control can be ignored.

Diferencias en la composición corporal y somatotipo de escolares de etnia mapuche y no mapuche de la comuna de Temuco - Chile / Ethnic differences in body composition and somatotype in mapuche and non-mapuche school children from Temuco - Chile

Los cambios culturales y demográficos en la etnia Mapuche chilena, han generado modificaciones en estilos de vida y la estructura morfofuncional de su población, incentivando de esta forma el estudio del estado de salud en jóvenes chilenos. El objetivo de este estudio fue analizar las diferencias en composición corporal y somatotipo entre niños Mapuche y no-Mapuche de la Comuna de Temuco en Chile. Participaron 122 niños Mapuche y 146 niños no-Mapuche entre 10 y 13 años. Se recogieron medidas de peso, talla; pliegues cutáneos y diámetros óseos; siguiendo el protocolo de la Sociedad Internacional para el desarrollo de la cineantropometría (ISAK). Se determinó el índice de masa corporal (IMC), estado nutricional, grasa corporal total y somatotipo (endomorfía, mesomorfía y ectomorfía). Los resultados indican que los niños Mapuche de 10 años presentaron valores menores de IMC (p0,01), grasa corporal total (p 0,001), así como de endomorfia y mesomorfia (p0,01) respecto a los no-Mapuche. Los niños Mapuche de 11-12 años presentaron valores menores de grasa corporal total (p0,01) y de endomorfia y ectomorfia (p0,05), comparados con los no-Mapuche. Los niños Mapuches de 13 años presentaron valores menores de grasa corporal total (p0,001) y de endomorfia y ectomorfía (p0,01) que el no-Mapuche. Los escolares Mapuches tienen menor grasa corporal que los niños no-Mapuche, el somatotipo predominante en la etnia Mapuche es el mesomórfico, observándose un componente endomórfico menor cuanto mayor es la edad. Son necesarias políticas de salud pública en los jóvenes, fundamentalmente educativa, para garantizar niveles adecuados de calidad de vida en ambas poblaciones Mapuches y no-Mapuche.

The cultural and demographic development of modern society has also affected the Mapuche ethnia and has influenced changes in lifestyles and in the morphofunctional structure of the population, particularly in young people. The purpose of this study was to determine differences in body composition and somatotype between Mapuche and non-Mapuche children from Temuco, Chile. A total of 122 Mapuche and 146 non-Mapuche children between 10 and 13 years old participated in the study. The measurements included were weight, height, skinfold thickness of triceps, subscapularis, supraspinatus and calf; perimeters of contracted and relaxed arm, waist and calf circumference; and humeral and femoral diameters, all following the procedures reference manual (ISAK). Several indexes were calculated: Body Mass Index (BMI), weight status (underweight, normoweight, overweight, obesity), total body fat (fat mass, percentage of fat mass and percentage of fat mass >20% of obesity) and finally, somatotype (endomorph, ectomorph, mesomorph). Ten year-old Mapuche children had lower values for BMI (p 0,01), total body fat (p0.001), and endomorphic and mesomorphic values (p0.01), compared to non Mapuche children. Mapuche children of 11-12 years of age had lower values for total body fat (p0.01), and endomorphic and ectomorphic values (p0.05), compared to non-Mapuche children. Thirteen year-old Mapuche children had lower values for total body fat (p0.001), and endomorphic and ectomorphic values (p0.01), compared to non-Mapuche children. Mapuche children had lower fat mass than non-Mapuche children, and the main somatotype among Mapuche children is mesomorphic with a reduction of the endomorphic component with increasing age. Public policy for youth is required, mainly educational, to guarantee appropriate levels of quality of life for both Mapuche and non-Mapuche populations.

Condición física y riesgo cardiovascular futuro en niños y adolescentes argentinos: una introducción de la batería ALPHA / Physical fitness and future cardiovascular risk in argentine children and adolescents: an introduction to the ALPHA test battery

Introducción. Altos niveles de condición física están relacionados con la salud cardiovascular de niños y adolescentes. Actualmente, en Argentina, no existe la aplicación sistemática de una batería para evaluar la condición física en el ámbito escolar. El propósito principal del estudio fue aplicar la batería ALPHA para determinar la condición física en una muestra de niños y adolescentes argentinos, y establecer la proporción de sujetos con nivel de capacidad aeróbica indicativo de riesgo cardiovascular futuro. Población y métodos. Una muestra de 1867 participantes (967 mujeres) de entre 6 y 19,5 años fueron evaluados con la batería ALPHA. Se midieron cuatro componentes de la condición física: 1) morfológico: estatura, peso corporal y perímetro de cintura; 2) muscular: test salto de longitud; 3) motor: test de velocidad/agilidad (carrera 4 x 10 m); 4) cardiorrespiratorio: test course navette de 20 m y cálculo del consumo máximo de oxígeno. Se calcularon los percentiles 5, 25, 50, 75 y 95 para los principales tests. Resultados. El índice de masa corporal medio fue 20,8 kg/m², y el 7,8% se clasificó en la categoría obesidad. Además, los participantes masculinos, en comparación con los femeninos, obtuvieron un mayor rendimiento en todos los tests de condición física (P < 0,001). En el 31,6% de los participantes se observó un nivel de capacidad aeróbica indicativo de riesgo cardiovascular. Conclusiones. La muestra de niños y adolescentes argentinos de sexo masculino presentó mayores niveles de condición física. Estas diferencias se incrementaron con la edad. Aproximadamente, 1 de cada 3 participantes tuvo un nivel de capacidad aeróbica indicativo de riesgo cardiovascular futuro.(AU)

Introduction. A high level of physical fitness is associated with cardiovascular health in children and adolescents. At present, there is no systematic implementation of a test battery to assess physical fitness at schools in Argentina. The main objective of this study was to implement the ALPHA test battery to determine the physical fitness of a sample made up of Argentine children and adolescents and to establish the proportion of subjects whose aerobic capacity is indicative of future cardiovascular risk. Population and methods. A sample of 1867 participants (967 girls) aged 6 to 19.5 years old assessed using the ALPHA test battery. Four components of physical fitness were measured: 1) morphological component: height, body weight, and waist circumference; 2) musculoskeletal component: standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) cardiorespiratory component: course-navette 20 m, shuttle run test and estimation of maximal oxygen consumption. The 5th, 25th, 50th, 75th, and 95th percentiles were estimated for the main tests. Results. The mean body mass index was 20.8 kg/m2, and 7.8% of participants were classified as obese. In addition, male participants had a better performance in all physical fitness tests when compared to girls (p< 0.001). An aerobic capacity indicative of cardiovascular risk was observed in 31.6% of all participants. Conclusions. Argentine male children and adolescents included in the sample showed higher levels of physical fitness. Such differences increase with age. Approximately one every three participants had an aerobic capacity indicative of future cardiovascular risk.(AU)

Condición física y riesgo cardiovascular futuro en niños y adolescentes argentinos: una introducción de la batería ALPHA / Physical fitness and future cardiovascular risk in argentine children and adolescents: an introduction to the ALPHA test battery

Introducción. Altos niveles de condición física están relacionados con la salud cardiovascular de niños y adolescentes. Actualmente, en Argentina, no existe la aplicación sistemática de una batería para evaluar la condición física en el ámbito escolar. El propósito principal del estudio fue aplicar la batería ALPHA para determinar la condición física en una muestra de niños y adolescentes argentinos, y establecer la proporción de sujetos con nivel de capacidad aeróbica indicativo de riesgo cardiovascular futuro. Población y métodos. Una muestra de 1867 participantes (967 mujeres) de entre 6 y 19,5 años fueron evaluados con la batería ALPHA. Se midieron cuatro componentes de la condición física: 1) morfológico: estatura, peso corporal y perímetro de cintura; 2) muscular: test salto de longitud; 3) motor: test de velocidad/agilidad (carrera 4 x 10 m); 4) cardiorrespiratorio: test course navette de 20 m y cálculo del consumo máximo de oxígeno. Se calcularon los percentiles 5, 25, 50, 75 y 95 para los principales tests. Resultados. El índice de masa corporal medio fue 20,8 kg/m², y el 7,8% se clasificó en la categoría obesidad. Además, los participantes masculinos, en comparación con los femeninos, obtuvieron un mayor rendimiento en todos los tests de condición física (P < 0,001). En el 31,6% de los participantes se observó un nivel de capacidad aeróbica indicativo de riesgo cardiovascular. Conclusiones. La muestra de niños y adolescentes argentinos de sexo masculino presentó mayores niveles de condición física. Estas diferencias se incrementaron con la edad. Aproximadamente, 1 de cada 3 participantes tuvo un nivel de capacidad aeróbica indicativo de riesgo cardiovascular futuro.

Introduction. A high level of physical fitness is associated with cardiovascular health in children and adolescents. At present, there is no systematic implementation of a test battery to assess physical fitness at schools in Argentina. The main objective of this study was to implement the ALPHA test battery to determine the physical fitness of a sample made up of Argentine children and adolescents and to establish the proportion of subjects whose aerobic capacity is indicative of future cardiovascular risk. Population and methods. A sample of 1867 participants (967 girls) aged 6 to 19.5 years old assessed using the ALPHA test battery. Four components of physical fitness were measured: 1) morphological component: height, body weight, and waist circumference; 2) musculoskeletal component: standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) cardiorespiratory component: course-navette 20 m, shuttle run test and estimation of maximal oxygen consumption. The 5th, 25th, 50th, 75th, and 95th percentiles were estimated for the main tests. Results. The mean body mass index was 20.8 kg/m2, and 7.8% of participants were classified as obese. In addition, male participants had a better performance in all physical fitness tests when compared to girls (p< 0.001). An aerobic capacity indicative of cardiovascular risk was observed in 31.6% of all participants. Conclusions. Argentine male children and adolescents included in the sample showed higher levels of physical fitness. Such differences increase with age. Approximately one every three participants had an aerobic capacity indicative of future cardiovascular risk.

Physical fitness and future cardiovascular risk in argentine children and adolescents: an introduction to the ALPHA test battery.

INTRODUCTION: A high level of physical fitness is associated with cardiovascular health in children and adolescents. At present, there is no systematic implementation of a test battery to assess physical fitness at schools in Argentina. The main objective of this study was to implement the ALPHA test battery to determine the physical fitness of a sample made up of Argentine children and adolescents and to establish the proportion of subjects whose aerobic capacity is indicative of future cardiovascular risk. POPULATION AND METHODS: A sample of 1867 participants (967 girls) aged 6 to 19.5 years old assessed using the ALPHA test battery. Four components of physical fitness were measured: 1) morphological component: height, body weight, and waist circumference; 2) musculoskeletal component: standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) cardiorespiratory component: course-navette 20 m, shuttle run test and estimation of maximal oxygen consumption. The 5th, 25th, 50th, 75th, and 95th percentiles were estimated for the main tests. RESULTS: The mean body mass index was 20.8 kg/m2, and 7.8% of participants were classified as obese. In ddition, male participants had a better performance in all physical fitness tests when compared to girls (p< 0.001). An aerobic capacity indicative of cardiovascular risk was observed in 31.6% of all participants. CONCLUSIONS: Argentine male children and adolescents included in the sample showed higher levels of physical fitness. Such differences increase with age. Approximately one every three participants had an aerobic capacity indicative of future cardiovascular risk.

Physical fitness and future cardiovascular risk in argentine children and adolescents: an introduction to the ALPHA test battery. / Physical fitness and future cardiovascular risk in argentine children and adolescents: an introduction to the ALPHA test battery.

INTRODUCTION: A high level of physical fitness is associated with cardiovascular health in children and adolescents. At present, there is no systematic implementation of a test battery to assess physical fitness at schools in Argentina. The main objective of this study was to implement the ALPHA test battery to determine the physical fitness of a sample made up of Argentine children and adolescents and to establish the proportion of subjects whose aerobic capacity is indicative of future cardiovascular risk. POPULATION AND METHODS: A sample of 1867 participants (967 girls) aged 6 to 19.5 years old assessed using the ALPHA test battery. Four components of physical fitness were measured: 1) morphological component: height, body weight, and waist circumference; 2) musculoskeletal component: standing long jump test; 3) motor component: speed/agility test (4x10 m shuttle run); 4) cardiorespiratory component: course-navette 20 m, shuttle run test and estimation of maximal oxygen consumption. The 5th, 25th, 50th, 75th, and 95th percentiles were estimated for the main tests. RESULTS: The mean body mass index was 20.8 kg/m2, and 7.8

of participants were classified as obese. In ddition, male participants had a better performance in all physical fitness tests when compared to girls (p< 0.001). An aerobic capacity indicative of cardiovascular risk was observed in 31.6

of all participants. CONCLUSIONS: Argentine male children and adolescents included in the sample showed higher levels of physical fitness. Such differences increase with age. Approximately one every three participants had an aerobic capacity indicative of future cardiovascular risk.