IntroductionMeasurement 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.MethodsA 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 discussionThere 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 R2 = 0.07 in males and R2 = 0.02 in females. While in the non-linear model (cubic), the values were: R2 = 0.50 to 0.51 in men and R2 = 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.

Background The relationship between the Body Mass Index (BMI) with physical fitness in children and adolescent populations from diverse regions are consistent. However, the relationship between the Ponderal Index (PI) with physical fitness, based on what is known to date, has not been examined in depth. The objective was to evaluate the relationships between BMI and PI with three physical fitness tests of students living at moderate altitudes in Peru. Methods A descriptive correlational study was carried out with 385 adolescents, between the ages of 10.0 to 15.9 years old, from the province of Arequipa, Peru. Weight, height, and three physical fitness tests (horizontal jump, agility, and abdominal muscle resistance) were evaluated. BMI and PI were calculated, and they were, then, categorized into three strata (low, normal, and excessive weight). Specific regressions were calculated for sex, using a non-lineal quadratic model for each item adjusted for BMI and PI. Results The relationship between BMI and PI with the physical tests reflected parabolic curves that varied in both sexes. The regression values for BMI in males oscillated between R2 = 0.029 and 0.073 and for females between R2 = 0.008 and 0.091. For PI, for males, it varied from R2 = 0.044 to 0.82 and for females, from R2 = 0.011 to 0.103. No differences occurred between the three nutritional categories for BMI as well as for PI for both sexes (p range between 0.18 to 0.38), as well as for low weight (BMI vs PI), normal weight (BMI vs PI), and excessive weight (BMI vs PI) (p range between 0.35 to 0.64). Conclusions BMI showed inferior quadratic regressions with respect to the PI. In addition, physical performance was slightly unfavorable when it was analyzed by BMI. PI could be a useful tool for analyzing and predicting physical fitness for adolescents living at a moderate altitude since it corrects for the notable differences for weight between adolescents.

La actitud de los docentes frente a la inclusión es un factor clave si queremos avanzar hacia el desafío de contar con comunidades educativas cada vez más inclusivas. El objetivo de este estudio busca validar un cuestionario sobre la actitud docente frente a la inclusión educativa en Chile. Se efectúa un estudio descriptivo –survey, de corte transversal–transeccional, no experimental, con una muestra no probabilística (accidental). Para ello se encuesta a 497 docentes que se desempeñan en escuelas municipales de Chile. Se utiliza un cuestionario con escala Lickert con 19 preguntas, para determinar la actitud frente a la inclusión. La medida de Kaiser-Meyer-Olkin KMO fue 0.893 y la prueba de esfericidad de Bartlet fue altamente significativa (X2= 4196.261, gl = 171, sig 0,000). Por otro lado, las cargas factoriales en las 19 preguntas oscilaron entre < 0.500 a 0.899 y la fiabilidad en general evidenció un Alpha de Cronbach (r=0.85). Se verifica, por tanto, que el cuestionario es válido y confiable en Chile para determinar la actitud docente frente a la inclusión educativa.

The components of physical fitness, aerobic capacity and anthropometric characteristics play an important role in maintaining and protecting cardiorespiratory functioning during all stages of life. The purpose of this study was to analyze the relationship between body fat indicators and aerobic capacity of students in a physical education program. A descriptive study (cross-sectional) was carried out with 110 physical education university students (75 males and 35 females). Ages ranged between 17.7 and 26.1 years old. Weight, standing height, sitting height, waist circumference (WC), and seven skinfolds (mm) were evaluated. Body Mass Index (BMI) was calculated. The Navette test (20m back and forth run) was used to assess the students. The correlations between adiposity and aerobic capacity for males varied from r= -0.21 to 0.34 and for females, from r= -0.21 to 0.34. In general, greater body adiposity (BMI, WC, and skinfolds) was a determinant in the males (R2= 14 to 27%). For the females, the Σ 7 skinfolds explained 11% of the adiposity. Males and females classified as having a high level of aerobic capacity showed less fat tissue (Σ 7 skinfolds) than those with moderate and low aerobic capacity (p<0.05). The results from this study indicated that body adiposity expressed as fat tissue limited aerobic capacity in a greater proportion of the males than in the females. The youth classified with high aerobic capacity showed less body fat than their counterparts classified as having moderate and low levels of aerobic capacity.