Research Outputs

Now showing 1 - 10 of 17
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    Publication
    Fiabilidad y estabilidad del gesto de diferentes variantes de lanzamiento de balonmano
    (MHSalud, 2022)
    Andrades-RamĆ­rez, Oscar
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    Alfaro-Castillo, Bryan
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    MartĆ­nez-GarcĆ­a, DarĆ­o
    ;
    ; ;
    Chirosa-RĆ­os, Luis
    El estudio tiene como propĆ³sito analizar la fiabilidad de la prueba de 8 lanzamientos de 3 diferentes variantes de lanzamientos de balonmano en estudiantado universitario. 33 varones, 20 Ā±1,9 aƱos peso 72,39Ā±8,9 kg altura 176,75 Ā±6,07 cm IMC 23,14Ā±2,3. Los sujetos participantes fueron evaluados en 2 sesiones separadas entre sĆ­ por un lapso de una semana. Ejecutaron lanzamientos hasta quedar registrados 8 mediciones en cada una de las pruebas, lanzamientos inespecĆ­ficos, en apoyo y en carrera con 3 pasos, se registrĆ³ la velocidad de lanzamiento con un radar posterior a la porterĆ­a. La fiabilidad del promedio de las puntuaciones del test de 8 medidas entre la primera sesiĆ³n y la segunda con una prueba test-retest, se obtuvieron los siguientes resultados: en el lanzamiento inespecĆ­fico se obtuvo un ICC= (0,86) entre el 95% de confianza, un de CV= (7,43%) y un ES= (0,08). Para el lanzamiento con apoyo se obtuvo un ICC= (0,94) al 95 % de confianza, un de CV= (4,71 %) y un ES= (-0,09). Para el lanzamiento con carrera se obtuvo un ICC= (0,96) al 95 % de confianza, un de CV= (4,00 %) y un ES= (0,05). Este estudio ha demostrado que la prueba de 8 lanzamientos y las 3 variantes es una medida de rendimiento confiable y estable para estudiantes de nivel universitario sin experiencia en el balonmano, en relaciĆ³n con las variables del lanzamiento, las 3 fueron fiables, solo la variable inespecĆ­fica fue menor en comparaciĆ³n al lanzamiento con apoyo y con carrera.
  • Publication
    A new reliable device to assess trunk extensors strength
    (Acta of Bioengineering and Biomechanics, 2021) ; ;
    Reyes-Ferrada, Waleska
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    Chirosa-RĆ­os, Luis
    ;
    Chirosa-RĆ­os, Ignacio
    ;
    MartĆ­nez-GarcĆ­a, DarĆ­o
    ;
    Jerez-Mayorga, Daniel
    ;
    Rodrƭguez-Perea, Ɓngela
    Purpose: This study aimed to examine the reliability of trunk extensor strength assessment with a functional electromechanical dynamometer (FEMD). Methods: Thirty-one men performed strength assessment at different velocities (V) (V1 = 0.15 mĀ·sāˆ’1, V2 = 0.30 mĀ·sāˆ’1, V3 = 0.45 mĀ·sāˆ’1) and range of movement (R) (R1 = 25% cm; R2 = 50% cm), and isometric contraction at 90Āŗ. Reliability was obtained through the intraclass correlation coefficient (ICC), typical error (TE), and coefficient of variation (CV). Results: The absolute reliability provided stable repeatability of the average eccentric strength in the V1R1 condition (CV = 9.52%) and the maximum eccentric strength in V1R1 (CV = 9.63%) and V2R2 (CV = 9.66%). The relative reliability of the trunk extensorā€™s average strength was good (ICC = 0.77ā€“0.83) for concentric and good (ICC = 0.78ā€“0.85) and moderate (ICC = 0.67ā€“0.74) for eccentric contraction. Also, good (ICC = 0.77ā€“0.81) and moderate (ICC = 0.55ā€“0.74) reliability of the maximum strength were obtained for concentric and eccentric contraction. The most reliable manifestation to evaluate the concentric (CV = 11.33%) and eccentric (CV = 9.52%) strength was the average strength in the V1R1 condition and the maximum strength (CV = 10.29%) to isometric assessment. The average concentric strength in the V2R2 condition (r = 0.69) and the maximum eccentric strength in the V1R1 condition (r = 0.65) were the best related to the maximum isometric strength. Conclusions: FEMD is a highly reliable device to evaluate trunk extensors strength.
  • Publication
    Anthropometric characteristics and functional fitness of Chilean community-dwelling older adults
    (NutriciĆ³n Hospitalaria, 2017) ;
    Guede-Rojas, Francisco
    ;
    Javier-Chirosa, Luis
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    Fuentealba, Sergio
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    Vergara, CĆ©sar
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    Salazar, Sergio
    ;
    MƔrquez, HƩctor
    ;
    Barboza, Paola
    Introduction: Anthropometry and functional fitness (FF) are fundamental aspects for functional independence conservation of older adults (OA). However, little has been investigated in chilean OA. Objective: To analyze anthropometric and FF characteristics of non-disabled OA. Methods: One hundred and sixteen subjects participated in the study. It was determined the prevalence of weight categories (Body Mass Index [BMI]) and cardiometabolic risk (CMR) (Waist Circumference [WC], Waist-Hip Ratio [WHR] and Waist-to-Height ratio [WHtR]). Additionally, "under the norm" physical performance and performance standards (Senior Fitness Test Battery [SFT]). Anthropometric and FF differences were analyzed according sex and age categories. Results: A total of 63.8% and 73.5% of men and women respectively were overweight. The highest prevalence of CMR was obtained through WHtR and the tests with the highest prevalence of low performance were 2-minute step Test and Back scratch Test. The performance standard was reached in 29.7% and 17.3%, in men and women respectively. Men presented greater height, WHR, strength and aerobic capacity. Women had greater hip circumference, BMI, WHtR and flexibility. These results tends to be maintained in the analyzes according age categories. Conclusions: The studied sample presented a high prevalence of overweight, CMR and low physical performance especially in women. Due its low cost and complexity, it is proposed that integral evaluation of anthropometric and FF parameters should be implemented in primary care programs aimed to preserving functionality of OA.
  • Publication
    Evaluation of tactical performance in invasion team sports: A systematic review
    (Routledge, 2018)
    Ɓvila-Moreno, Francisco Manuel
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    Chirosa RĆ­os, Luis Javier
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    UreƱa-EspƔ, Aurelio
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    Lozano-Jarque, Demetrio
    ;
    The objectives of this revision were to identify game indicators, the references for evaluating tactical efficiency, and the types of data analysis used in invasion team sports for the analysis of tactical performance. A search of the principal electronic databases was carried out, the procedure was adjusted to the PRISMA-P 2015 protocol, and 62 non-experimental published articles were obtained from the years 2000ā€“2016. The results showed the complimentary use of diverse types of indicators and the frequent elaboration of instruments ad hoc. The individual technical-tactical actions were widely used. The record of standardised team actions was scarce. The research lines with a sequential data record for their temporary analysis were significant. The transitory or final score and the results of game sequences were the most used references of performance. The big data tools of analysis, web analysis, and the detection of temporal patterns or the application of polar coordinates were emerging methods of analysis.
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    Publication
    Efecto de los juegos reducidos en la composiciĆ³n corporal y la condiciĆ³n fĆ­sica aerĆ³bica en un grupo de adolescentes escolares
    (Revista mƩdica de Chile, 2015)
    Carrasco BeltrƔn, Hernaldo
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    Reigal Garrido, Rafael E.
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    ;
    Chirosa RĆ­os, Ignacio JesĆŗs
    ;
    Chirosa RĆ­os, Luis Javier
    The regular practice of physical activity contributes to weight control and improves maximal oxygen uptake (VO2max), socialization and quality of life. Aim: To determine the effect of moderate-to-vigorous physical activity on body composition and VO2max in a group of overweight school-age males. Material and Methods: We studied fifty-five overweight males aged 15.6 Ā± 0.7 years. Participants were divided in two groups (experimental and control groups). The intervention in the experimental group was the practice of small-sided games during 60 minutes, two days per week and during 11 weeks. At baseline and the end of the intervention, body composition was measured using bioimpedance and VO2max was calculated using the Course Navette test. Results: A 7% reduction in the percentage of body fat and a 9% increase in VO2max were observed in the experimental group (p < 0.01). No changes were recorded in the control group. Conclusions: Eleven weeks of small-sided exercises performed twice per week increased VO2max and reduced fat mass in overweight adolescents.
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    Association between physical fitness parameters and health related quality of life in Chilean community-dwelling older adults
    (Revista mƩdica de Chile, 2017) ; ;
    Guede-Rojas, Francisco
    ;
    Chirosa-RĆ­os, Luis
    ;
    Fuentealba-Urra, Sergio
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    Vergara-RĆ­os, CĆ©sar
    ;
    Campos-Jara, Christian
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    Barbosa-GonzƔlez, Paola
    Background: There is no conclusive evidence about the association between physical fitness (PF) and health related quality of life (HRQOL) in older adults. Aim: To seek for an association between PF and HRQOL in non-disabled community-dwelling Chilean older adults. Material and Methods: One hundred and sixteen subjects participated in the study. PF was assessed using the Senior Fitness Test (SFT) and hand grip strength (HGS). HRQOL was assessed using eight dimensions provided by the SF-12v2 questionnaire. Binary multivariate logistic regression models were carried out considering the potential influence of confounder variables. Results: Non-adjusted models, indicated that subjects with better performance in arm curl test (ACT) were more likely to score higher on vitality dimension (OR > 1) and those with higher HGS were more likely to score higher on physical functioning, bodily pain, vitality and mental health (OR > 1). The adjusted models consistently showed that ACT and HGS predicted a favorable perception of vitality and mental health dimensions respectively (OR > 1). Conclusions: HGS and ACT have a predictive value for certain dimensions of HRQOL.
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    Publication
    Reliability of a standing isokinetic shoulder rotators strength test using a functional electromechanical dynamometer: effects of velocity
    (PEERJ, 2020)
    Martinez Garcia, Dario
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    Rodriguez Perea, Angela
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    Barboza, Paola
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    ;
    Jerez Mayorga, Daniel
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    Chirosa, Ignacio
    ;
    Chirosa RĆ­os, Luis Javier
    Background. The evaluation of the force in internal rotation (IR) and external rotation (ER) of the shoulder is commonly used to diagnose possible pathologies or disorders in the glenohumeral joint and to assess patientā€™s status and progression over time. Currently, there is new technology of multiple joint isokinetic dynamometry that allows to evaluate the strength in the human being. The main purpose of this study was to determine the absolute and relative reliability of concentric and eccentric internal and external shoulder rotators with a functional electromechanical dynamometer (FEMD). Methods. Thirty-two male individuals (21.46 Ā± 2.1 years) were examined of concentric and eccentric strength of shoulder internal and external rotation with a FEMD at velocities of 0.3 m sāˆ’1 and 0.6 m sāˆ’1 . Relative reliability was determined by intraclass correlation coefficients (ICC). Absolute reliability was quantified by standard error of measurement (SEM) and coefficient of variation (CV). Systematic differences across velocities testing circumstances, were analyzed with dependent t tests or repeated measures analysis of variance in case of two or more than two conditions, respectively. Results. Reliability was high to excellent for IR and ER on concentric and eccentric strength measurements, regardless of velocity used (ICC: 0.81ā€“0.98, CV: 5.12ā€“8.27% SEM: 4.06ā€“15.04N). Concentric outcomes were more reliable than eccentric due to the possible familiarization of the population with the different stimuli. Conclusion. All procedures examined showed high to excellent reliability for clinical use. However, a velocity of 0.60 m sāˆ’1 should be recommended for asymptomatic male patients because it demands less time for evaluation and patients find it more comfortable.
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    TĆ©cnica de secuencias de bracing sobre el rendimiento del karate y la estabilidad del core
    (D.A.A. Scientific Section, 2022) ;
    Chirosa-RĆ­os, I.
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    Chirosa Rios, L.
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    MartĆ­nez-GarcĆ­a, D.
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    Herbawi, F.
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    Jerez-Mayorga, D.
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    Baena-Morales, S.
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    RodrĆ­guez-Perea, A.
    El objetivo de este estudio fue determinar el efecto de la tĆ©cnica de secuencias de bracing en la estabilidad del core y el rendimiento en kata de karatecas. 38 deportistas masculinos de karate participaron en el estudio divididos en un grupo experimental (n=21) y un grupo de control (n=17). La prueba de rendimiento del deportista y la prueba de estabilidad del core se realizaron en pretest y postest posterior a 8 semanas de programa de estabilidad del core (tĆ©cnica de secuencias de bracing). El grupo experimental mostrĆ³ una mejora significativa en la prueba de rendimiento del atleta (p < 0,001) y en la prueba de estabilidad del core con (p < 0,05). Hubo una correlaciĆ³n positiva muy fuerte entre la prueba de rendimiento del atleta y el cinturĆ³n del karateca (Ļ =0.780), una correlaciĆ³n positiva considerable entre la prueba de estabilidad del core y el cinturĆ³n del jugador (Ļ =0.604), una correlaciĆ³n positiva considerable entre la prueba de rendimiento del atleta y la edad del jugador (Ļ=0.554), y una correlaciĆ³n positiva media entre la prueba de estabilidad del core y la edad del jugador (Ļ=0.481). En conclusiĆ³n, los karatecas mostraron una gran mejora en el rendimiento del kata y en el nivel de estabilidad del core despuĆ©s del programa de tĆ©cnicas de secuencias de bracing.
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    The addition of very light loads into the routine testing of the bench press increases the reliability of the forceā€“velocity relationship
    (PeerJ, 2018) ; ;
    Barboza GonzƔlez, Paola
    ;
    Chirosa RĆ­os, Luis Javier
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    GarcĆ­a-Ramos, Amador
    Background: The aim of this study was to examine whether the addition of very light loads for modeling the forceā€“velocity (Fā€“V) relationship during the bench press (BP) exercise can confirm its experimental linearity as well as to increase the reliability and concurrent validity of the Fā€“V relationship parameters (maximum force (F0), maximum velocity (V0), Fā€“V slope, and maximum power (Pmax)). Method: The Fā€“V relationship of 19 healthy men were determined using three different methods: (I) 6-loads free method: six loads performed during the traditional free-weight BP exercise (ā‰ˆ 1ā€“8ā€“29ā€“39ā€“49ā€“59 kg), (II) 4-loads free method: four loads performed during the traditional free-weight BP exercise (ā‰ˆ 29ā€“39ā€“49ā€“59 kg), and (III) 4-loads Smith method: four loads performed during the ballistic bench press throw exercise in a Smith machine (ā‰ˆ 29ā€“39ā€“49ā€“59 kg). Results: The linearity of the Fā€“V relationship was very high and comparable for the three Fā€“V methods (p = 0.204; median Pearsonā€™s correlation coefficient (r) = 0.99). The three methods were ranked from the most to the least reliable as follows: 6-loads free (coefficient of variation (CV) range = 3.6ā€“6.7%) > 4-loads Smith (CV range = 4.6ā€“12.4%) > 4-loads free (CV range = 3.8ā€“14.5%). The higher reliability of the 6-loads free method was especially pronounced for Fā€“V slope (CVratio ā‰„ 1.85) and V0 (CVratio ā‰„ 1.49) parameters, while the lowest difference in reliability was observed for F0 (CVratio ā‰¤ 1.27). The 6-loads free and 4-loads free methods showed a very high concurrent validity respect to the 4-loads Smith method for F0 and Pmax (r ā‰„ 0.89), a moderate validity for the Fā€“V slope (r = 0.66ā€“0.82), and a low validity for V0 (r ā‰¤ 0.37). Discussion: The routine testing of the Fā€“V relationship of upper-body muscles through the BP exercise should include trials with very light loading conditions to enhance the reliability of the Fā€“V relationship.
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    Publication
    Reliability of isometric and isokinetic trunk flexor strength using a functional electromechanical dynamometer
    (PeerJ, 2019)
    Rodriguez-Perea, Angela
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    Chirosa RĆ­os, Luis J.
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    Martinez-Garcia, Dario
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    ;
    Guede Rojas, Francisco
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    Jerez-Mayorga, Daniel
    ;
    Chirosa Rios, Ignacio J.
    Aim. To determine the absolute and relative reliability of functional trunk tests, using a functional electromechanical dynamometer to evaluate the isokinetic strength of trunk flexors and to determine the most reliable assessment condition, in order to compare the absolute and relative reliability of mean force and peak force of trunk flexors and to determine which isokinetic condition of evaluation is best related to the maximum isometric. Methods. Test-retest of thirty-seven physically active male student volunteers who performed the different protocols, isometric contraction and the combination of three velocities (V1 = 015 m sāˆ’1, V2 = 0.30 m sāˆ’1, V3 = 0.45 m sāˆ’1) and two range of movement (R1 = 25% cm ; R2 = 50% cm) protocols. Results. All protocols to evaluate trunk flexors showed an absolute reliability provided a stable repeatability for isometric and dynamic protocols with a coefficient of variation (CV) being below 10% and a high or very high relative reliability (0.69 < intraclass correlation coefficient [ICC] > 0.86). The more reliable strength manifestation (CV = 6.82%) to evaluate the concentric contraction of trunk flexors was mean force, with 0.15 m sāˆ’1 and short range of movement (V1R1) condition. The most reliable strength manifestation to evaluate the eccentric contraction of trunk flexors was peak force, with 0.15 m sāˆ’1 and a large range of movement (V1R2; CV = 5.07%), and the most reliable way to evaluate isometric trunk flexors was by peak force (CV = 7.72%). The mean force of eccentric trunk flexor strength with 0.45 m sāˆ’1 and short range of movement (V3R1) condition (r = 0.73) was best related to the maximum isometric contraction. Conclusion. Functional electromechanical dynamometry is a reliable evaluation system for assessment of trunk flexor strength.