Body surface area is a predictor of maturity status in school children and adolescents.

BACKGROUND: Generally, Body surface area (BSA) changes significantly during growth and maturation. These increases portend a possible relationship between body size as determined by BSA with maturational status in children and adolescents. OBJECTIVE: To determine the relationship between maturity status (MS) obtained by non-invasive anthropometric methods and body surface area (BSA) in children and adolescents of both sexes in a regional population of Chile. Additionally, we sought to verify the type of linear or nonlinear relationship between MS and BSA in both sexes. METHODS: A descriptive (cross-sectional) study was designed in 950 children and adolescents of both sexes (539 males and 411 females). The age range ranged from 6.0 to 17.9 years. Anthropometric measurements were evaluated: body weight, standing height, sitting height. MS was assessed by means of two non-invasive anthropometric techniques. Both techniques predict peak years of growth velocity (APHV) through a regression equation for each sex. BSA (m2) was estimated by means of the Haycock equation. RESULTS: The R2 in the linear model is relatively lower (R2 = 0.80 to 0.89 in males and 0.74 to 0.66 in females) in relation to the nonlinear quadratic model (R2 = 0.81 in males and 0.76 to 0.69). The quadratic nonlinear quadratic model reflected an adequate fit (RMSE) for the data set, being in men (RMSE = 1.080 and 1.125), while in women (RMSE = 1.779 and 1.479). CONCLUSION: BSA is positively associated with MS determined by two non-invasive methods in Chilean children and adolescents: The nonlinear quadratic model was a better fit to the data distribution. The results suggest the use of BSA as a possible predictor of maturity status in Chilean youth.

Systematic review of the anthropometric profile of female futsal players 2010-2020.

The objective was to summarize the scientific literature on the anthropometric characteristics of female futsal players. A systematic review documentary study was carried out. SCOPUS, PUBMED and SCIELO databases were used to search for information on primary studies related to the anthropometric profile of women's indoor soccer (elite and non-elite). The keywords used were: futsal, female, anthropometry. The range of years for the search was from 2010 to 2020. To analyze anthropometric differences, two groups were formed: group A: elite and group B: non-elite. 31 primary studies were identified, 22 (71%) in Scopus, 5 (16.1%) in PUBMED and 4 (12.9%) in SCIELO. Three publication languages were considered (English, Spanish and Portuguese) and 6 countries were identified (Brazil, Spain, Iran, Turkey, Venezuela and Italy). Players in the elite group evidenced higher weight, height, and BMI relative to their non-elite counterparts. Discrepancy in anthropometric characteristics between elite and non-elite players was verified. These results suggest that in order to participate in competitions at the highest level in women's futsal, they should have greater weight, height and BMI than their non-elite counterparts.

Fat-free mass and maturity status are determinants of physical fitness performance in schoolchildren and adolescents

Abstract Objectives: The objective of the study was to verify whether (FFM), maturity status (MS) and chronological age (CA) are determinants of physical fitness performance, and to analyze FFM and physical performance aligned by CA and MS in children and adolescents. Methods: A descriptive correlational study was carried out in 863 schoolchildren. Weight, height, and waist circumference (WC) were evaluated. Body mass index (BMI), FFM, fat mass (FM), MS (Age at peak height velocity, APHV) were calculated. The physical tests of velocity 20 m, agility 5 m × 10rep, and horizontal jump (HJ) were evaluated. Results: The APHV was estimated in boys at 14.0 ± 0.36APHV and in girls at 11.96 ± 0.49APHV. The relationships between CA and APHV with FFM was r = 0.80 in boys and r = 0.44 to 0.45 in girls. The relationships between FFM and physical tests in boys were [HJ (r = 0.70), agility 5m × 10rep (r = -0.68), velocity (r = -0.61)] and in girls [HJ (r = 0.42), agility 5m × 10rep (r = -0.52), velocity (r = -0.20)]. The differences in FFM and physical fitness tests were more pronounced when aligned by APHV than by CA. Conclusion: It was verified that both FFM, CA, and APHV are determinants of physical fitness performance. In addition, the APHV should be introduced in physical education as a means of ranking physical performance among schoolchildren.

Fat-free mass and maturity status are determinants of physical fitness performance in schoolchildren and adolescents.

OBJECTIVES: The objective of the study was to verify whether (FFM), maturity status (MS) and chronological age (CA) are determinants of physical fitness performance, and to analyze FFM and physical performance aligned by CA and MS in children and adolescents. METHODS: A descriptive correlational study was carried out in 863 schoolchildren. Weight, height, and waist circumference (WC) were evaluated. Body mass index (BMI), FFM, fat mass (FM), MS (Age at peak height velocity, APHV) were calculated. The physical tests of velocity 20 m, agility 5 m x 10rep, and horizontal jump (HJ) were evaluated. RESULTS: The APHV was estimated in boys at 14.0 ± 0.36APHV and in girls at 11.96 ± 0.49APHV. The relationships between CA and APHV with FFM was r = 0.80 in boys and r = 0.44 to 0.45 in girls. The relationships between FFM and physical tests in boys were [HJ (r = 0.70), agility 5m x 10rep (r = -0.68), velocity (r = -0.61)] and in girls [HJ (r = 0.42), agility 5m x 10rep (r = -0.52), velocity (r = -0.20)]. The differences in FFM and physical fitness tests were more pronounced when aligned by APHV than by CA. CONCLUSION: It was verified that both FFM, CA, and APHV are determinants of physical fitness performance. In addition, the APHV should be introduced in physical education as a means of ranking physical performance among schoolchildren.

Comparación de parámetros antropométricos y de composición corporal de futbolistas profesionales / A Comparison of Anthropometric Parameters and the Body Composition of Professional Soccer Players

Resumen El presente estudio tuvo por objetivo comparar los parámetros antropométricos y de composición corporal en futbolistas profesionales en cinco temporadas. Se efectuó un estudio transversal (comparativo). Se estudió a 120 futbolistas, donde cada cohorte por año se evaluó a 24 futbolistas. El rango de edad fue de 18 a 37 años. Se evaluó a los futbolistas al inicio de cada temporada en los años 2012 a 2016: Se midió el peso, la estatura, seis pliegues cutáneos (Tríceps, subescapular, supra-iliaco, abdominal, muslo y pantorrilla). Se calculó el Índice de Masa corporal IMC, % de grasa, la masa grasa y masa libre de grasa MLG. El tejido adiposo se agrupó en tres grupos (brazo: (tricpes+subescapular, tronco: suprailiaco+abdominal, Piernas: muslo+pantorrilla). Hubo diferencias en el peso corporal, la estatura, la sumatoria de los 6 pliegues y la MLG a lo largo de los 5 años. [año 2012 (Peso: 76,6±7.8kg, estatura: 177.6±5.7cm, Pliegues: 58.7±12.8mm, MLG: 64.5±6.3mm), año 2013: (Peso: 77.8±6.4kg, Estatura: 178,4±4.4, Pliegues: 60.1±15.9mm, MLG:66.3±3.5mm), año 2014: (Peso: 74.9±5.7kg, Estatura: 177.0±5.8cm, Pliegues: 54.4±14.7mm, MLG: 64.5±4.5kg), año 2015: (Peso: 74.1±6.8kg, Estatura: 176.1±5.5cm, Pliegues: 54.9±15.6mm, MLG: 63.8±4.6kg), año 2016: (Peso: 72.7±kg, Estatura: 175.3±6.9kg, Pliegues: 50.8±12.mm, MLG: 62.8±5.9kg)]. Este estudio verificó que el perfil antropométrico y el tejido adiposo de los futbolistas fueron disminuyendo en cada temporada, mientras que la MLG reflejó similares valores en cada uno de las cohortes evaluadas.

Abstract The present cross-sectional (comparative) study aimed to compare the anthropometric and body composition parameters in professional soccer players over five seasons. It was conducted on 120 soccer players grouped in a cohort of 24 subjects per year. The age range was 18 to 37 years. The footballers were evaluated at the beginning of each season from 2012 to 2016; weight, height, six skin folds (triceps, subscapularis, supra-iliac, abdominal, thigh, and calf) were evaluated from 2012 to 2015. The Body Mass Index (BMI), fat percentage, fat mass, and FFM were calculated. The adipose tissue was grouped into three groups: arm (triceps + subscapular), trunk (supra iliac + abdominal), and legs (thigh + calf). Body weight, height, the sum of the 6 folds, and the MLG varied during the 5 years. For 2012 the results were the following: Weight, 76.6 ± 7.8kg; Height, 177.6 ± 5.7cm; Folds, 58.7 ± 12.8mm; MLG, 64.5 ± 6.3mm). In 2013, these were the results: Weight, 77.8 ± 6.4kg; Height, 178, 4 ± 4.4; Folds, 60.1 ± 15.9mm; MLG, 66.3 ± 3.5mm). These were the measures obtained in 2014: Weight, 74.9 ± 5.7kg; Height, 177.0 ± 5.8cm; Folds, 54.4 ± 14.7mm; MLG, 64.5 ± 4.5kg ). And these were of the year 2015: Weight, 74.1 ± 6.8kg; Height, 176.1 ± 5.5cm; Folds, 54.9 ± 15.6mm; MLG, 63.8 ± 4.6kg). Finally, in 2016 these were the measures collected: Weight, 72.7 ± kg; Height, 175.3 ± 6.9 kg; Folds, 50.8 ± 12.mm; MLG, 62.8 ± 5.9kg. This study verified that the soccer players' anthropometric profile and adipose tissue decreased each season, while the MLG reflected similar values in each of the evaluated cohorts.

Resumo O presente estudo teve como objetivo comparar os parâmetros antropométricos e de composição corporal em jogadores profissionais de futebol durante cinco temporadas. Foi realizado um estudo transversal (comparativo). Foi estudado um total de 120 jogadores de futebol, onde cada coorte por ano foram avaliados 24 jogadores. A faixa etária era de 18 a 37 anos. Os futebolistas foram avaliados no início de cada temporada, nos anos de 2012 a 2016. Foram medidas altura, peso, seis dobras da pele (tríceps, subescapular, supra ilíaca, abdominal, coxa e calcanhar). Foram calculados índice de massa corporal IMC, % de gordura, massa de gordura e massa livre de gordura MLG. O tecido adiposo foi agrupado em três grupos (braço: tríceps + subescapular, tronco: suprailíaco + abdominal, pernas: coxa + calcanhar). Houve diferenças no peso corporal, na altura, a soma de 6 dobras e a MLG ao longo dos 5 anos: ano 2012 (Peso: 76,6±7,8kg, Altura: 177,6±5,7cm, Dobras: 58,7±12,8mm, GLM: 64,5±6,3mm), ano 2013 (Peso: 77,8±6,4kg, Altura: 178,4±4,4, Dobras: 60,1±15,9mm, GLM:66,3±3.5mm), ano 2014 (Peso: 74,9±5,7kg, Altura: 177,0±5,8cm, Dobras: 54,4±14,7mm, GLM: 64,5±4,5kg), ano 2015 (Peso: 74,1±6,8kg, Altura: 176,1±5,5cm, Dobras: 54,9±15,6mm, GLM: 63,8±4,6kg), ano 2016 (Peso: 72,7±kg, Altura: 175,3±6,9kg, Dobras: 50,8±12,mm, GLM: 62,8±5,9kg). Este estudo verificou que o perfil antropométrico e o tecido adiposo dos jogadores de futebol diminuíram em cada temporada, enquanto que a MLG refletiu valores similares em cada um dos coortes avaliados.

Reference values for bone density and bone mineral content from 5 to 80 years old in a province of Chile.

Background: The assessment of bone health throughout the life cycle is essential to determine fracture risk. The objectives of the work were (a) compare bone mineral density and content with international references from the United States, (b) determine maximum bone mass, (c) propose references for bone health measurements from ages 5 to 80 years old. Methods: Research was carried out on 5,416 subjects. Weight and height were measured. Body Mass Index (BMI) was calculated. The total body was scanned using dual energy X-ray absorptiometry (DXA). Information was extracted from the bone health measures (bone mineral density (BMD) and bone mineral content (BMC)) for both sexes, according to pediatric and adult software. Results and Discussion: Differences were identified between the mean values of Chilean and American men for BMD (~0.03 to 0.11 g/cm2) and BMC (~0.15 to 0.46 g). Chilean females showed average values for BMD similar to the US references (~-0.01 to 0.02 g/cm2). At the same time, they were relatively higher for BMC (~0.07 to 0.33 g). The cubic polynomial regression model reflected a relationship between BMD and BMC with chronological age in both sexes. For males, R2 was higher (R2 = 0.72 and 0.75) than for females (R2 = 0.59 and 0.66). The estimate of maximum bone mass (MBM) for males emerged at 30 years old (1.45 ± 0.18 g/cm2 of BMD and 3.57 ± 0.60 g of BMC) and for females at age 28 (1.22 ± 0.13 g/cm2 of BMD and 2.57 ± 0.44 g of BMC). The LMS technique was used to generate smoothed percentiles for BMD and BMC by age and sex. Results showed that maximum bone mass occurred in females at age 28 and in males at 30. Reference values obtained from this research may be used to evaluate bone health, diagnose bone fragility and osteoporosis in individuals and regional population groups.

Relationship between age and handgrip strength: Proposal of reference values from infancy to senescence.

Introduction: Measurement of hand grip strength (HGS) has been proposed as a key component of frailty and has also been suggested as a central biomarker of healthy aging and a powerful predictor of future morbidity and mortality. Objectives: (a) To determine whether a nonlinear relationship model could improve the prediction of handgrip strength (HGS) compared to the linear model and (b) to propose percentiles to evaluate HGS according to age and sex for a regional population of Chile from infancy to senescence. Methods: A cross-sectional descriptive study was developed in a representative sample of the Maule region (Chile). The volunteers amounted to 5,376 participants (2,840 men and 2,536 women), with an age range from 6 to 80 years old. Weight, height, HGS (right and left hand) according to age and sex were evaluated. Percentiles were calculated using the LMS method [(L (Lambda; asymmetry), M (Mu; median), and S (Sigma; coefficient of variation)]. Results and discussion: There were no differences in HGS from 6 to 11 years of age in both sexes; however, from 12 years of age onwards, males presented higher HGS values in both hands (p < 0.05). The linear regression between age with HGS showed values of R 2 = 0.07 in males and R 2 = 0.02 in females. While in the non-linear model (cubic), the values were: R 2 = 0.50 to 0.51 in men and R 2 = 0.26 in women. The percentiles constructed by age and sex were: P5, P15, P50, P85, and P95 by age range and sex. This study demonstrated that there is a nonlinear relationship between chronological age with HGS from infancy to senescence. Furthermore, the proposed percentiles can serve as a guide to assess and monitor upper extremity muscle strength levels at all stages of life.

Systematic review of aquatic physical exercise programs on functional fitness in older adults.

The practice of physical exercise is recommended in the prevention of the deterioration of neuromuscular functions in aging. The objectives of this systematic review were to describe the protocols used and the functional fitness indicators evaluated in aquatic exercise programs in adults aged 50 to 80 years. The Pubmed database was used. The keywords were: 1) Physical exercise program or protocols or duration or type of exercise or aquatic exercise, frequency or intensity or indicators; 2) Adults or older adults; 3) Training or indicators, functional fitness, physical fitness. The search strategy considered the components of the Population, Interventions, Comparators, Outcomes, and Study design (PICOS) tool. Nine experimental studies were identified. These studies developed protocols to improve functional fitness in adults aged 50 to 80 years. They were based on sessions of 2 to 5 per week, the work time per session was 30 to 60min, intensities varied between 50 to 95% and totaled between 4 to 24 weeks of intervention. The activities were based on aquatic gymnastic exercises aimed at muscular strengthening of the upper and lower extremities, as well as coordination, balance, agility, cycling and walking exercises submerged in water. The protocols developed to improve functional fitness in adults aged 50 to 80 years were based on general physical exercise prescription guidelines (frequency, duration, intensity and type of activity). The application of aquatic exercises based on gymnastic exercises can provoke positive responses on functional fitness if worked at least 2 to 5 times per week, 30 to 60min/day and at intensities of 50 to 95%. These systematized indicators can be used by professionals working with adults to create and promote aquatic programs to improve functional fitness.

Regulation data for the horizontal jump of children and adolescents.

The Horizontal Jump (HJ) is a daily tool that could be used to categorize the level of muscle fitness performance of the lower limbs. The goal was to compare the muscle fitness with those of international studies and to propose percentiles to assess the HJ performance of children and adolescents. A cross-sectional study was conducted. A total number of 3023 children and adolescents between the ages of 6.0 to 17.9 were studied. Weight, height, waist circumference (WC), and lower limb muscle fitness were evaluated. The student HJ performance values in Chile were inferior when compared to HJ performance in Brazil, Poland and Europe. For the Greek study, differences occurred only from age 6 to 15 years old. In comparison to Colombia, students showed better muscle fitness performance. These differences appeared in childhood and lasted until the beginning of adolescence. Percentiles were created to assess the lower limb fitness being an easy tool to be used and applied to classify lower limb strength.

Pruebas de aptitud física que realizan los escolares / Physical fitness tests in schoolchildren

The objective was to determine the types of studies that have been carried out according to year and region and to verify the physical tests used according to physical fitness dimensions from 2010 to 2018. A systematic review was carried out. Physical fitness (study types and physical tests) was studied in Chile. The PubMed database was used, considering the period from 2010 to 2018. The keywords used in Spanish were: aptitud física, niños y adolescentes, Chile, and in English: physical aptitude, children and adolescents. The information was recorded on an observation sheet and for the data, the PRISM flow chart was used. 18 studies were identified. 88.9% are descriptive (cross-sectional) studies, 11.1% quasi-experimental. 38.9% were made in the Metropolitan region, 33.3% in Maule, 11% in Araucanía, 5.6% for each region of Los Lagos, Ñuble, and other unspecified regions. In the muscular dimension, it was determined that 38.9% used the manual clamping force and 50% the horizontal leap. In the cardiorespiratory dimension, 27.8% applied the Course-Navette test, 16.7% the 6-minute walk test, and 11% the 100-meter speed test. A high number of descriptive (cross-sectional) investigations were identified and the most commonly used physical tests were horizontal leap, manual clamping force, Course-Navette test, and 6-minute walk test. These results suggest the need to develop experimental and longitudinal studies, as well as the inclusion of morphological and motor dimensions in their protocols

El objetivo fue determinar los tipos de estudio que se han efectuado según año y región, y verificar las pruebas físicas utilizadas según dimensiones de la aptitud física durante 2010 a 2018. Se efectuó una revisión sistemática. Se estudió la aptitud física (tipos de estudio y pruebas físicas) en Chile. Se utilizó la base de datos PubMed, considerando el período 2010 a 2018. Las palabras clave utilizadas fueron, en español: aptitud física, niños y adolescentes, Chile, y en inglés: physical aptitude, children and adolescents. La información se registró en una ficha de observación y para la organización de datos se utilizó el diagrama de flujo PRISMA. Se identificaron 18 estudios. El 88.9% son de tipo descriptivo (transversales); el 11.1%, cuasiexperimentales. El 38.9% se efectuó en la región Metropolitana; el 33.3%, en El Maule; 11%, en la Araucanía; 5.6% para cada región de Los Lagos, Ñuble y no especificada. En la dimensión muscular, se determinó que el 38.9% utilizó la fuerza de prensión manual y el 50% el salto horizontal. En la dimensión cardiorrespiratoria, el 27.8% aplicó el test de Course Navette; el 16.7%, la caminata de 6 minutos, y el 11%, la prueba de velocidad de 100 metros. Se identificó un elevado número de investigaciones descriptivas (transversales) y las pruebas físicas más utilizadas fueron salto horizontal, fuerza de presión manual prueba de Course Navette y la caminata de 6 minutos. Estos resultados sugieren la necesidad de desarrollar estudios experimentales y longitudinales, así como la inclusión de dimensiones morfológicas y motoras en sus protocolos