Marco Cossio-Bolaños’s research while affiliated with Universidad San Ignacio de Loyola and other places

Background Young soccer players, club professionals and soccer academies require to monitor and evaluate the state of maturity. This will allow decisions to be made in the process of selection and detection of sports talent. Objective a) To determine which of the two equations (Mirwald and Moore) is more adequate to analyze physical performance in young soccer playersnd b) to propose reference values to evaluate the physical condition of young Chilean soccer players according to maturity stage. Methods A descriptive cross-sectional study was carried out in 302 young Chilean soccer players between 11 and 16 years of age. Weight, standing height, sitting height and seven physical tests were evaluated: Hand grip strength (HGS) [(right and left], explosive strength [horizontal jump (HJ), squat jump (SJ), and countermovement jump (CMJ)], agility (Illinois and 5x10 repetitions) and aerobic fitness (distance in meters and VO2max). Maturity status (MS) was estimated using two equations: Mirwald and Moore for men. Percentiles were calculated using the LMS method (L = lambda for the skewness; M = mu for the median; S = sigma). Results MS was estimated by Mirwald at 13.8 ± 0.60 years and by Moore at 13.18 ± 0.47 years. HGS (right and left) were higher by Moore's method from 1 to 4%. With the explosive strength tests (HJ, CMJ and SJ), the values were higher from 1 to 3%. With the agility tests (Illinois and 5x10repetitions), the explanatory power was higher from 2 to 4%. With the aerobic fitness values (meters run and VO2max), the values were higher from 1 to 3% in relation to the Mirwald method. Percentiles (P3, P5, P10, P15, P25, P50, P75, P85, P90, P95 and P97) were developed for the physical tests according to Moore's MS (-2APHV, -1APHV, 0APHV, +1APHV and + 2APHV). Conclusion Moore's equation is more adequate than Mirwald's to analyze physical performance in young Chilean soccer players aged 11 to 16 years. Percentiles based on maturity status can be used to categorize, monitor and evaluate physical performance during the growth and development of young soccer players.

Excess body weight is associated with increased mortality, low physical fitness and low levels of physical activity. The objective this study to verify the linear and nonlinear (quadratic) relationships between Body Mass Index (BMI) and lower limb strength in children and adolescents of both sexes in a region of Chile. A descriptive (cross-sectional) study was carried out in children and adolescents of school age (6 to 17 years) of both sexes. The sample size was 863 schoolchildren (500 males and 363 females). Weight, height and the Horizontal Jump test (HJ) were evaluated. BMI and BMI z -score were calculated according to age and sex. In males, the explanatory power in the linear model [R= 0.15, R2= 0.02, Root Mean Square Error (RMSE)= 39.6] is lower than the non-linear quadratic model (R= 0.22, R2= 0.05, RMSE= 39.0). In females, the explanatory power in the linear model (R= 0.12, R2= 0.02, RMSE= 23.2) is lower than the quadratic nonlinear model (R= 0.19, R2= 0.04, RMSE= 22.9). In the BMI z-score scale, males presented HJ values of: [Low BMI 145.4±39.5cm, normal 164.2±33.6cm, and high BMI 109.0±23.2cm]. In females it was: [Low BMI 108.0±23.0cm, normal 113.5±36.3cm, and elevated BMI 91.5±30.4cm]. The study verified a curvilinear relationship in the form of a parabola (quadratic) between BMI and the HJ test in children and adolescents of both sexes. Schoolchildren in the extreme BMI categories (low and high BMI) reflected low performance in the HJ in relation to school-children with normal BMI.

The biceps curl test is easy to apply, does not require expensive equipment, and its short execution time makes it feasible in school settings with limited resources. To verify the reliability of the biceps curl test in children and adolescents and to provide reference values according to chronological age and sex. A total of 1103 schoolchildren aged 6 to 17 years (500 boys and 603 girls) were evaluated. Weight and height were evaluated and Body Mass Index (BMI) and Tri Ponderal Index (TPI) were calculated. The right and left hand biceps curl was evaluated in 30 s. Children aged 6 to 11 years used a 1 kg dumbbell and those aged 12 to 17 years used a 2 kg dumbbell. Percentiles were calculated using the LMS method. The values of the relative Technical Error of Measurement (TEM%) of the biceps curl test of both hands ranged from 0.48 to 2.89%. The intraclass correlation coefficient (ICC) evidenced high values of 0.93 to 0.99. The Bland-Altman plot showed wide limits of agreement (-1.28 to 1.29 rep). These findings demonstrate that the test is reliable and consistent for use in pediatric populations and is suitable for different stages of physical development in school children. The values showed stability and wide limits of agreement. In addition, the proposed percentiles are useful to evaluate and monitor the strength endurance performance of both arms.

Caring skills are essential in the training of nursing professionals, because they allow them to learn and gain experience in the quality and compassionate care of future patients. The objective is to compare the Caring Skills (CS) in nursing students according to age range, experience and family environment. A descriptive comparative study was carried out. The sample consisted of 176 nursing students from a Peruvian university. The age range was 18 to 27 years. A patient care skills scale was applied. This scale has three indicators (knowledge, courage and patience) and 37 questions. There were no differences in the three indicators (knowledge, courage and patience) when compared by age range (P>0.05). There were significant differences when compared by age range between students living with family and living alone (P<0.05). There was no difference between students who had experience vs. those who had no experience in patient care (P>0.05). It was determined that age and living with family members are determinant in the CS of nursing students of a Peruvian university. There were no differences between experienced and inexperienced students.

Objective The evaluation of bone health during the growth stage is extremely important, as it is a key factor to prevent bone diseases in adulthood. The objectives of the study were: a) to verify if there are differences in bone health with other geographic regions, b) to develop bone health curves using quantitative ultrasonography (QUS) through the Broadband Ultrasonic Attenuation (BUA) parameter in children and adolescents residing in a high altitude region of Peru and c) to determine specific cut-off points for bone health assessment in this particular population. Methods A cross-sectional study was carried out in schoolchildren in a high altitude region of Peru. The sample consisted of 1468 children and adolescents (724 males and 744 females). The age range was 6.0 to 17.9 years old. Weight and height were evaluated. Body Mass Index (BMI) was calculated. Bone quality was evaluated by quantitative ultrasonography (QUS) of the calcaneus. The parameters measured were Speed of Sound (SOS, m/s); Broadband Ultrasonic Attenuation (BUA, dB/MHz); and Bone Quality Index (BQI= αSOS+αBUA, αβ: temperature corrections). Results There were small discrepancies in bone health (BUA) between studies from various geographic regions. Values differed across all age ranges from ~0.36 to ~10.86 in males and from ~0.26 to ~6.68 in females. At later ages during adolescence the values are relatively similar, reaching a plateau around 16 and 17 years of age. Percentiles were calculated for BUA by age and sex. Sensitivity and specificity values in females are slightly higher relative to males. However, the Youden Index reflects 0.84 for both sexes and the appropriate cut-off point for men is ≤67.8 and for women is ≤63.7. Conclusion The study demonstrated that there are small discrepancies in bone health (BUA) among children between children and adolescents from different geographic regions. These findings support the creation of specific references and cut-off points for bone health in the pediatric population of a high altitude region of Peru. The results suggest the application of percentiles for the assessment of bone health in school and epidemiological contexts.

Background The evaluation of Hand Grip Strenght (HGS) is relevant for the early detection of muscle weakness. It may be an early indicator of juvenile sarcopenia and other alterations associated with neuromuscular disorders. Objective a) to compare hand grip strength (HGS) with other regional studies and b) to propose reference values of HGS by age, sex in children and adolescents living in a moderate altitude region of Peru. Methodology: A cross-sectional study was designed in school children and adolescents living in a moderate altitude region of Peru (2320 meters above sea level). The sample selection was non-probabilistic (accidental), considering 1058 schoolchildren (557 boys and 501 girls) with an age range of 6 to 17 years. These schoolchildren came from public schools. Weight, height and Body Mass Index (BMI) were assessed. HGS of both hands (right, left and both hands) was evaluated. The p50th percentile was used to compare discrepancies with studies from Chile, Colombia and Peru. Results The median values (p50) of both hands show a linear increase with advancing age. It is expected that HGS tends to increase as children get older. The maximum HGS of both hands occurred in males at 17 years of age (38.87kg/f). While in females it was at 15–16 years (23.56kg/f). Discrepancies in HGS were observed when comparing the 50th percentile (P50) of schoolchildren living at moderate altitude in Peru with regional studies carried out in Chile, Colombia and Peru. HGS percentiles by age and sex were developed for the left, right and both hands (P3, P5, P15, P25, P50, P75, P85, P90, P95 and P97). Conclusion The study demonstrated discrepancies in HGS between schoolchildren living in a moderate altitude region of Peru and neighboring regions. This allowed us to propose percentiles to evaluate HGS by age and sex. The results suggest its use in educational and clinical contexts.

Explosive strength is fundamental in the performance of athletes. The objective is to identify the criteria used for the prescription of Explosive Strength Training (EST) and to verify the changes it produces in futsal players. A systematic review of studies analyzing the criteria used for the prescription of explosive strength training was conducted in PubMed/MEDLINE and Scielo, considering the period between 2017 and 2023. The search strategy used the terms: players, Futsal, Futsal training, strength, physical exercise, explosive strength, intervention, experimental study. Data extraction included: year of publication, country, sample, protocol performed (content and activity developed, duration, intensity, frequency, total weeks). A total of six studies were identified. Fifty percent of the studies were developed in Brazil, the others in Italy, Spain and Portugal. Five studies applied a training of 2 sessions per week and one indicated 2-3 sessions. Three studies describe the training sessions (study 1: 15-30 minutes, study 2: 20-25 minutes, study 3: 1 hour). Five studies used 1RM and one study used subjective perception of exertion (PSE). The contents of the interventions were varied, from squats with weights, accelerations and decelerations, leg press, leg extension, plyometrics. The training criteria for explosive strength were: intensity controlled by a 1RM, frequency of 2 to 3 sessions per week, duration of 15 to 30 minutes per session and the training contents were varied. These results suggest positive changes in CMJ, increasing explosive strength from ∼2.0 to 4.6 cm (5.8 to 13.7%). These findings highlight the need to develop a more standardized protocol to optimize the benefits of explosive strength training in this athletic population.

Realizar un análisis bibliométrico integral de la productividad científica relacionada con programas de intervención que buscan mejorar la función cognitiva en adultos mayores, según revista, país y tema de intervención en la base de datos pubmed. Se realizó un estudio bibliométrico durante el periodo 2018 al 2023. La búsqueda bibliográfica se realizó en la base de datos PubMed. Los términos de búsqueda fueron: cognitivecayden, cognitivecayden, exercise program, intervention program, physical exercise,older adult, elderly. Cada artículo identificó: año de publicación, idioma de publicación, país de publicación, nombre de la revista y tema del estudio. Se utilizaron los lineamientos establecidos por PRISMA. Se incluyeron 51 publicaciones científicas, analizadas en 34 revistas. China lidera con 14 estudios (27,5%), seguido de Estados Unidos con 5 artículos (9,8%). Corea y Singapur están en tercer lugar con 4 estudios cada uno (7,8%), seguido de Japón con 3 estudios (5,9%). En cuanto al idioma de publicación, el 96,1% (n=49) fueron publicados en inglés. Solo el 3,9% (n=2) fueron publicados en español. La revista con mayor frecuencia de publicaciones fue Nutrients, con 6 artículos publicados, lo que representa el 11,8% del total y destaca como líder en este campo. Le siguió BMC Geriatrics con 3 artículos publicados, lo que representa el 5,9% del total. Destaca el aumento de las investigaciones sobre intervenciones para el deterioro cognitivo en OA, concentradas principalmente en los años 2020 y 2023. China lidera la producción de estudios seguida de Estados Unidos, Corea y Singapur. Los programas de intervención más estudiados incluyen el ejercicio y el deporte, seguido de la nutrición y el entrenamiento computarizado. Destaca la revista “Nutrients” con mayor número de artículos, seguida de “BMC Geriatrics”.

Background Health-related physical fitness (HRPF) attributes are considered important markers beneficial to various health outcomes. However, the literature is divergent regarding HRPF and bone health in adulthood, especially due to the end of the second and beginning of the third decades of life when the peak bone mass period occurs. Objective To analyze which HRPF variables are areal bone mineral density (aBMD) predictors in adult males and females. Methods This study evaluated 137 healthy young adults aged 18–25 years (50% males). Dual-energy X-ray absorptiometry (DXA) was used to estimate fat mass and lean mass and aBMD, hand grip strength test, sit-ups test, flexibility test, lower limb muscle strength and 20-meter run were used to evaluate physical fitness. Multiple linear regression using the backward method was used to analyze bone mineral density predictors by sex. Results HRPF indicators showed correlations from R = 0.28 in the right femoral neck aBMD to R = 0.61 in the upper limbs aBMD in males; in females, correlations from R = 0.27 in total body aBMD to R = 0.68 in the lower limbs aBMD were found. In males, body mass and HRPF indicators were aBMD predictors with HRPF indicators explaining variance from R²=0.214 in the lumbar spine to R²=0.497 in the upper limbs, and in females, with the exception of the lumbar spine, variance from R²=0.237 in the right femoral neck aBMD to R²=0.442 in the lower limbs aBMD was found. Conclusion Health-related physical fitness components were able to predict aBMD in different anatomical regions in young adults, especially muscle strength and cardiorespiratory fitness indicators for males, while only lean mass and fat mass for females.

Introduction Falls in older adults are a common and serious threat to health and functional independence. It can cause psychological distress, inability to participate in activities of daily living, brain injury, fractures, and even death. The aim was to analyze the psychometric properties of the self-assessed fall risk scale (FRS) that measures the risk of falls in older adults in a central region of Chile, as well as to verify the concurrent validity against functional fitness tests. Materials and methods A descriptive cross-sectional study was carried out in 222 older adults (OA) [34 males and 188 females] with an age range of 65 to 85 years. The 13-item self-perceived fall risk scale (FRS) was validated. Anthropometric measures (weight, height and waist circumference) were assessed. Five functional fitness tests were measured (right and left hand grip strength, biceps curl, up-and-go, agility and 6-minute walk test). Validation was performed by construct validation [(exploratory factor analysis (EFA) and confirmatory factor analysis (CFA)] and concurrent validity. Results The EFA revealed 4 factors in the FRS scale [1: fear of falling (variance 27.1%), 2: use of assistive devices (variance 10.6%), 3: loss of sensation (variance 9.3%), and 4: limited mobility (variance 8.3%)]. Factor loadings ranged from ∼ 0.50 to 0.83 across the 4 components. The Kaiser-Meyer Olkin sample adequacy test (KMO) reflected adequate adequacy (KMO = 0.79, chi-square (X2) = 498.806, gl = 78, p = 0.00). The CFA showed a satisfactory final fit [chi-square (X2) = 126.748, Root mean squared error of approximation (RMSEA) = 0.042, Tucker-Lewis Index (TLI) = 0.946, Comparative fit index (CFI) = 0.935 y Normed fit index (NFI) = 0.90. The relationships between the FRS scale and functional fitness tests (right and left hand grip strength, biceps curl, up-and-go, agility and 6-minute walk test) ranged from low to moderate (r= -0.23 to 0.41). Conclusion The FRS scale showed acceptable validity and reliability in older adults in central region of Chile. It is expected that this scale will be useful for assessing fall risk in clinical and epidemiological settings in the aging Chilean population.