Dr. Ulloa-Díaz, David

Background: The Chilean population has experienced increased longevity in recent decades, leading to an increased incidence of and mortality from neurodegenerative diseases such as Parkinson’s disease (PD). PD is a chronic degenerative condition that affects the central nervous system. The main objective of this research is to evaluate the effect of 12-week programs of tonic, isometric, and isometric/vibratory muscular strength training while controlling the manipulation of the intensity variable on motor and non-motor symptomatology in PD patients. The secondary objective is to assess the levels of muscular strength in PD patients and their relationship with motor and non-motor symptomatology. Methods: A parallel-group, randomized trial will randomly assign (n = 34) people of both sexes with Parkinson’s disease between stages I–III Hoehn and Yahr (H&Y), aged between 50 and 70 years to one of the experimental groups, in which they will undergo a total of 24 strength training sessions during 12 weeks. During the intervention period, the participants will be advised not to undertake additional exercise programs, to avoid substances that may disrupt metabolism and circadian cycles, and to maintain their medication regimen. The primary or motor evaluation of rest tremor will be performed with an accelerometer (Actigraphy), balance with the Mini-BESTest balance test, gait speed with the Ten Meters Walk Test, and non-motor symptomatology through anxiety, depression (MDS-UPDRS), and quality of life (PDQ-39) questionnaires. The Secondary evaluation of muscle strength will be performed with a functional electromechanical dynamometer. Discussion: Established as a hypothesis is that manipulating intensity variables in 12-week tonic, isometric, and isometric/vibratory muscle strength training programs has an effect on motor and non-motor symptomatology in people with Parkinson’s disease. The research will establish the extent to which controlled muscular strength training has an effect on relevant factors related to motor and non-motor symptomatology.

The purpose of the study was to analyze the test–retest reliability of an isometric and isometric/vibratory muscular strength protocol in the bilateral seated bench press (BSBP), bilateral seated rowing (BSR), unilateral seated right knee extension (USKER), and left knee extension (USKEL) tests controlled using functional electromechanical dynamometry (FEMD) in healthy young adults. A repeated measures design was used to determine the reliability of a muscular strength protocol in isometric and isometric vibration modes with FEMD. No significant differences were found in test–retest analysis (p > 0.05; ES < 0.20); and high reliability (CV = 4.65–5.02%; ICC = 0.99–0.98) was found for BSBP measures, and acceptable reliability (CV = 3.71–9.61%; ICC = 0.98–0.95) was found for BSR, USKER, and USKEL. Furthermore, the coefficients between the two measures were strong (r = 0.963–0.839) and highly significant (p = 0.001) for maximal strength in the isometric and maximal isometric/vibratory assessment of muscle strength in all muscle strength tests. This study demonstrates that isometric and maximal isometric/vibratory strength in the BSBP, BSR, USKER, and USKEL tests can be measured with high reliability and reproducibility using the FEMD.

Objective: This systematic review and meta-analysis aimed to (I) evaluate the evidence on the effects of high-intensity interval training (HIIT) on systolic blood pressure (SBP) and diastolic blood pressure (DBP) in hypertensive patients; (II) determine whether HIIT impacts SBP and DBP differently; and (III) assess the clinical relevance of these effects. Methods: A comprehensive search was conducted across multiple electronic databases, resulting in the inclusion of seven randomized clinical trials in the meta-analysis. The outcomes were analyzed using random-effects models to compute mean differences (MD) and standardized mean differences (SMD) for SBP and DBP. Results: A small reduction in SBP was observed with HIIT interventions (MD −3.00; 95% CI −4.61 to −1.39; p < 0.0001; SMD −0.28; 95% CI −0.42 to −0.13; p = 0.0003). However, no statistically significant reductions were detected for DBP (MD −0.70; 95% CI −1.80 to 0.39; p = 0.21; SMD −0.07; 95% CI −0.22 to 0.08; p = 0.35). Despite demonstrating statistical significance for SBP, the effects did not reach clinical relevance. Conclusions: HIIT interventions yield small reductions in SBP, with minimal impact on DBP. These findings suggest limited clinical relevance in the management of hypertension. Further randomized controlled trials are necessary to standardize HIIT protocols, with specific emphasis on intensity control and manipulation, to better understand their potential role in hypertensive populations.

Aumentar los niveles de actividad física (AF) tiene múltiples beneficios a lo largo de todo el ciclo de vital. Durante la infancia y la adolescencia se deben afianzar los hábitos de vida activa en niños y jóvenes para mantener o mejorar su bienestar físico, mental y el estado de salud actual y futuro. A fines de abril de 2020, aproximadamente 1.500 millones de niños y adolescentes, iniciaron su proceso de enseñanza-aprendizaje a distancia, debido al cierre de las escuelas en la mayoría de los países. El objetivo de este estudio fue analizar el nivel de AF de adolescentes de la comuna de Concepción después del periodo de confinamiento por COVID-19. Un total de 381 estudiantes de ambos sexos (203 hombres y 178 mujeres), entre 14 a 16 años de establecimientos educacionales secundarios participaron del estudio. Los resultados demostraron que los adolescentes presentan un nivel de AF clasificado como inactivos (PAQ-A = 2.53 puntos), los hombres presentan una diferencia significativa (p = .001) en comparación con el grupo de mujeres en el nivel de AF, se observa una diferencia significativa entre las distintas edades de los hombres (p = .027) y de las mujeres (p = .001), además, se observó una diferencia significativa entre los establecimientos educacionales (p = .012). La vuelta a la presencialidad y las estrategias implementadas para un mayor desarrollo de la AF después del periodo de confinamiento, obtuvieron un nivel bajo de AF de los estudiantes de educación secundaria en establecimientos educacionales particular subvencionado de la comuna de Concepción.

Background: Systematizing reliable protocols and procedures for strength assessment in handball has allowed for a more thorough kinetic analysis and increased precision in detecting training-induced changes in muscular strength. The evaluation of upper limb strength with a bilateral standing press (BSP) exercise in handball players approximates blocking actions in the defensive phase, pushing and fixation. Aim: The aim of this study was to analyze the relative and absolute reliability of intra-session comparisons in an isometric peak muscle strength protocol in a bilateral standing press (BSP) exercise among female handball players. Methods: Sixteen young female handball players at an international level, aged between 22 ± 4 years, with no prior experience in using functional electromechanical dynamometers (FEMD) participated in this study. The participants initiated the assessment of maximum isometric force in a bipedal stance with a forward projection of the dominant foot between 20 and 30 cm. The knees were kept semi-flexed, and the hip extension of the non-dominant limb ranged from 15 to 20°. Bilateral anterior push of the upper limb was performed with shoulder abduction and elbow flexion at 90°, maintaining a pronated hand position. Participants were instructed to exert three sets of maximal force for 5 s in BSP exercise. Relative reliability was assessed using the model intraclass correlation (ICC) and absolute reliability was assessed using the coefficient of variation (CV) and standard error of measurement (SEM). For this study, the parameters of maximum and mean muscle strength were considered. Results: The results demonstrated high relative reliability (ICC 0.93–0.97) and absolute reliability (SEM 0.19–2.79) y (CV 4.78–9.03) for both mean force and peak force, with no significant differences between the sets (p > 0.05), indicating a negligible effect size (0.01−0.12). Conclusion: The mean and peak isometric muscle strength for the BSP exercise controlled with FEMD in female handball players exhibits high relative and absolute reliability between series.

La percepción de la clase de educación física por parte de los estudiantes es un factor importante porque dependiendo de cómo los escolares perciban estas vivencias, se generarán determinadas creencias o valoraciones, las que influyen en la actitud para enfrentar estas experiencias corporales cada vez que se presenten. 176 estudiantes (14.74 ± 0.68), pertenecientes a los establecimientos particulares subvencionados de la comuna de Coronel. El objetivo de esta investigación es analizar la percepción actitudinal subjetiva de los estudiantes de enseñanza secundaria hacia los profesores de EF. Para evaluar la percepción actitudinal de los estudiantes hacia el profesor de educación física, se utilizó una modificación del cuestionario de actitudes de los escolares hacia la educación física. En los resultados de la actitudes positivas, se puede indicar que el alumnado valoro mayormente el ítem “Muy de acuerdo” en la pregunta “Mi profesor/a de educación física sabe mucho”, en las actitudes negativas la pregunta “Mi profesor/a de educación física levanta la voz frecuentemente” fue el mayor porcentaje en el ítem “Muy de acuerdo” . En el análisis comparativo entre hombres y mujeres para la percepción positiva reporto (p = 0.63) y negativa (p = 0.10). En el análisis por edades para la escala positiva (p = 0.01), para la escala negativa (p = 0.25). El alumnado observo mayormente actitudes positivas de y muy pocas negativas en el profesor de educación física, sin observase diferencias entre hombres y mujeres, en las edades se reportaron diferencias en las actitudes positivas y negativas del profesor, informando que los alumnos de con más edad evalúan más críticamente las actitudes positivas y negativas del profesor de EF.

El estudio tiene como propósito analizar la fiabilidad de la prueba de 8 lanzamientos de 3 diferentes variantes de lanzamientos de balonmano en estudiantado universitario. 33 varones, 20 ±1,9 años peso 72,39±8,9 kg altura 176,75 ±6,07 cm IMC 23,14±2,3. Los sujetos participantes fueron evaluados en 2 sesiones separadas entre sí por un lapso de una semana. Ejecutaron lanzamientos hasta quedar registrados 8 mediciones en cada una de las pruebas, lanzamientos inespecíficos, en apoyo y en carrera con 3 pasos, se registró la velocidad de lanzamiento con un radar posterior a la portería. La fiabilidad del promedio de las puntuaciones del test de 8 medidas entre la primera sesión y la segunda con una prueba test-retest, se obtuvieron los siguientes resultados: en el lanzamiento inespecífico 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 relación con las variables del lanzamiento, las 3 fueron fiables, solo la variable inespecífica fue menor en comparación al lanzamiento con apoyo y con carrera.

El objetivo de este estudio fue determinar el efecto de la técnica 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 (técnica de secuencias de bracing). El grupo experimental mostró 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 correlación positiva muy fuerte entre la prueba de rendimiento del atleta y el cinturón del karateca (ρ =0.780), una correlación positiva considerable entre la prueba de estabilidad del core y el cinturón del jugador (ρ =0.604), una correlación positiva considerable entre la prueba de rendimiento del atleta y la edad del jugador (ρ=0.554), y una correlación positiva media entre la prueba de estabilidad del core y la edad del jugador (ρ=0.481). En conclusión, los karatecas mostraron una gran mejora en el rendimiento del kata y en el nivel de estabilidad del core después del programa de técnicas de secuencias de bracing.

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 m·s−1, V2 = 0.30 m·s−1, V3 = 0.45 m·s−1) and range of movement (R) (R1 = 25% cm; R2 = 50% cm), and isometric contraction at 90º. 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 extensor’s average strength was good (ICC = 0.77–0.83) for concentric and good (ICC = 0.78–0.85) and moderate (ICC = 0.67–0.74) for eccentric contraction. Also, good (ICC = 0.77–0.81) and moderate (ICC = 0.55–0.74) 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.

The overhead throw is a fundamental technical-tactical ability for overhead sports. The purposes of this review are to assess the effect of resistance training (RT) in enhancing throwing velocity in athletes and to investigate the relationships between age or gender in this effect. Control group trials were identified through looking up electronic databases with a search span of 10th December 2020. Only studies which have control groups within research design, subjects randomly assigned to groups, healthy athletes with experience in the sport, an intervention consisting of a supervised RT program of a minimum duration of 4 weeks, and assessment of sport-specific throwing velocity were taken into account for this meta-analysis. A total of 16 studies with 424 subjects were deemed eligible per the inclusion criteria. The overall pooled analysis demonstrated that a large effect was observed for throwing velocity outcomes (ES 1.10; 95% CI 0.64–1.57; p < 0.00001). Differences were due to gender, with male (ES 1.12; 95% CI 0.55–1.78; p < 0.0001) and female athletes (ES 1.22; 95% CI 0.25–2.20; p < 0.00001). And due to age, with teenager athletes (ES 0.49; 95% CI -0.18–1.17; p = 0.04) and adult athletes (ES 1.34; 95% CI 0.64–1.92; p < 0.00001). Throwing velocity enhancement after RT was greater for women than for men, and for adults more than underage subjects. RT should last at least four weeks, with 2–3 sessions each week, and with any available implement.