Examinando por Autor "Ojeda-Aravena, Alex"
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Ítem A Systematic Review with Meta-Analysis on the Effects of Plyometric-Jump Training on the Physical Fitness of Combat Sport Athletes(MDPI, 2023-02) Ojeda-Aravena, Alex; Herrera-Valenzuela, Tomás; Valdés-Badilla, Pablo; Báez-San Martín, Eduardo; Thapa, Rohit K.; Ramirez-Campillo, RodrigoWe aimed to assess the athletic performance changes in combat sport athletes (CoSAs) after plyometric-jump training (PJT), compared to control conditions, through a systematic review with meta-analysis. Following PRISMA guidelines, three electronic databases were searched for includable articles, according to a PICOS approach. Using a random-effects model, Hedges’ g effects sizes (ES) were calculated. Heterogeneity was assessed using the I2 statistic, with values of <25%, 25–75%, and >75% representing low, moderate, and high levels of heterogeneity, respectively. Statistical significance was set at p ≤ 0.05. The certainty of evidence was assessed using the GRADE approach. Twelve eligible articles were identified for systematic review, seven of high quality and five of moderate quality, according to the PEDro scale. The studies recruited taekwondo, silat, wrestling, judo, fencing, and karate athletes (292 total participants), including specific–active and active controls. Most participants had a mean age of <18 years and were males (n = 225). Compared to the control, PJT programmes, involving 4–12 weeks and 2–3 sessions per week, induced small to moderate improvements (ES = 0.47 to 1.04) in athletes’ maximal strength (e.g., 1RM squat), vertical jump height, change-of-direction speed, and specific performance (e.g., fencing movement velocity), although without meaningful effects on body mass, fat mass, and muscle mass (ES = 0.02 to −0.06). Most (7 of 8) outcomes attained low heterogeneity. The outcome-level GRADE analysis indicated a certainty of evidence from low to moderate. In conclusion, PJT, when compared to control conditions, may improve CoSA athletic performance. © 2023 by the authors.Ítem Analysis of Magnitude and Direction of Body Composition Asymmetries in Male Brazilian Jiu-Jitsu Athletes: Pilot Study(Multidisciplinary Digital Publishing Institute (MDPI), 0025-02) Ojeda-Aravena, Alex; Kons, Rafael L; Azócar-Gallardo, Jairo; Dopico-Calvo, Xurxo; Fernández, Aida; Tuesta-Roa, Marcelo; Cresp-Barria, Mauricio; Olivares-Arancibia, Jorge; Báez-San Martín, EduardoIn order to optimize body composition and its components, it is of interest to analyze inter-limb asymmetries in athletes of popular combat sports such as Brazilian Jiu-Jitsu (BJJ). This study aimed to assess the magnitude and direction of body composition asymmetry in competitive male BJJ athletes. Seventeen experienced and competitive male BJJ athletes (age 34.59 ± 8.00 years, 172.94 ± 5.46 cm, BJJ experience 7.88 ± 5.57 years, and 3.71 ± 1.05 days of weekly volume training), including Guard Fighters (n = 7) and Pass Fighters (n = 10), participated in this study. In a single session, whole-body and segmental upper limb and lower limb body composition (BC) was assessed utilizing dual-energy X-ray absorptiometry (DXA). The assessment included total mass (TM), fat mass (FM), fat mass percentage (%FM), fat-free mass (FFM), and bone mineral content (BMC). Absolute differences between limbs were analyzed using a paired t-test. A comparison of BC asymmetries according to combat styles was conducted using an independent t-test. The effect size (ES) was interpreted as Cohen’s d. The main results revealed significant asymmetries in the upper limbs (ULs) of the total group; greater values were found on the left side for TM (p = 0.009, ES = 0.725), FM (p = 0.016, ES = 0.650), FFM (p = 0.026, ES = 0.594), and BMC (p < 0.001, ES = 0.993). In Pass Fighters, differences favored the right side in TM (p = 0.003, ES = 1.277), FM (p = 0.009, ES = 1.039), FFM (p = 0.011, ES = 1.000), and BMC (p < 0.001, ES = 1.916). In contrast, Guard Fighters showed no discrepancies in these parameters. No notable disparities were observed in the lower limbs. This pilot study reveals that BJJ athletes present significant asymmetries in BC, particularly in the ULs, with a marked predominance on the right side, especially in Pass Fighters. © 2025 by the authors.Ítem Effect of a Concurrent Training Program with and Without Metformin Treatment on Metabolic Markers and Cardiorespiratory Fitness in Individuals with Insulin Resistance: A Retrospective Analysis(Multidisciplinary Digital Publishing Institute (MDPI), 2024-11) Azócar-Gallardo, Jairo; Ojeda-Aravena, Alex; Báez-San Martín, Eduardo; Herrera-Valenzuela, Tomás; Tuesta, Marcelo; González-Rojas, Luis; Calvo-Rico, Bibiana; García-García, José ManuelBackground: Type 2 diabetes mellitus is a metabolic disorder characterized by insulin resistance (IR), which is prevalent worldwide and has significant adverse health effects. Metformin is commonly prescribed as a pharmacological treatment. Physical exercise is also recognized as an effective regulator of glycemia, independent of metformin. However, the effects of inter-day concurrent training (CT)—which includes both endurance and resistance exercises—combined with metformin treatment on metabolic markers and cardiorespiratory fitness in individuals with IR remain controversial. Objective: This study aimed to analyze the effects of a 12-week inter-day CT program on metabolic markers and cardiorespiratory fitness in overweight/obese individuals with IR, both with and without metformin treatment. Additionally, inter-individual responses to CT were examined. Materials and Methods: Data from the 2022–2023 Obesity Center database were retrospectively analyzed. According to the eligibility criteria, 20 overweight/obese individuals diagnosed with IR participated in a 12-week CT program (three weekly sessions: two endurance and one resistance exercise session). Participants were divided into three groups: the exercise group (E-G: n = 7, 32.86 ± 8.32 years, 85.2 ± 19.67 kg), the exercise–metformin group (E-MG: n = 6, 34.83 ± 12.91 years, 88.13 ± 12.66 kg), and the metformin-only control group (M-G: n = 7, 34.43 ± 13.96 years, 94.23 ± 13.93 kg). The M-G did not perform physical exercise during the 12 weeks but continued pharmacological treatment. Body composition, metabolic markers, and cardiorespiratory fitness were assessed before and after the 12-week CT program. Results: A group-by-time interaction was observed for fasting insulin (F2,17 = 34.059, p < 0.001, η2p = 0.88), the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) (F2,17 = 35.597, p < 0.001, η2p = 0.80), and maximal fat oxidation (MFO) (F2,17 = 4.541, p = 0.026, η2p = 0.348) following the CT program. The maximal oxygen uptake (VO2max) showed significant improvements in the E-G (F = 4.888, p = 0.041, ∆+13.3%). Additionally, the percentage of fat mass (%FM) and body mass (BM) were significantly reduced across all groups (F = 125.244, p < 0.001 and F = 91.130, p < 0.001, respectively). The BM decreased by ∆−9.43% in the E-G (five responders, Rs), ∆+9.21% in the EM-G (5 Rs), and ∆+5.15% in the M-G (3 Rs). The %FM was reduced in the E-G by ∆−22.52% (seven Rs). Fasting insulin and the HOMA-IR significantly improved in both the E-G and EM-G, with fasting insulin showing a ∆−82.1% reduction in the E-G (five Rs) and a ∆−85% reduction in the EM-G (six Rs). Similarly, the HOMA-IR improved by ∆+82.6% in the E-G (three Rs) and by ∆+84.6% in the EM-G (six Rs). Conclusions: The 12-week inter-day concurrent training program, whether combined with metformin or not, was similarly effective in improving metabolic markers in patients with insulin resistance as metformin treatment alone. Both exercise groups demonstrated a significant reduction in insulin sensitivity and an increase in maximal fat oxidation. Meanwhile, exclusive pharmacological treatment with metformin markedly decreased cardiorespiratory fitness, and consequently, fat oxidation.Ítem Validity, Reliability, and Sensitivity of Mobile Applications to Assess Change of Direction Speed(Termedia Publishing House Ltd., 2023) Uysal, Hüseyin Şahin; Ojeda-Aravena, Alex; Ulaş, Mehmet; Martín, Eduardo Báez-San; Ramirez-Campillo, RodrigoThis study aimed to assess the validity, reliability, and sensitivity of mobile applications for assessing change-of-direction speed (CODS) performance. Thirty college athletes performed two Illinois CODS tests during one session. Assessments were carried out simultaneously using six devices (the CODTimer app, Seconds Count app, StopwatchCamera app, two analog stopwatches, and timing gates). Validity analyses included Pearson's product-moment correlation analysis, a linear regression model, and Bland-Altman plots. Reliability analyses included the intraclass correlation coefficient (ICC), the coefficient of variation (CV%), and the paired-sample t test. Sensitivity analyses included the typical error and smallest worthwhile change (SWC). The results showed that validity, reliability, and sensitivity values were higher for the CODTimer app (r = 0.99, R2 = 0.99, mean bias = −0.03 ± 0.10, CV% = 3.21, ICC = 0.89, SWC rating: good, p = 0.84) and the Seconds Count app (r = 0.99, R2 = 0.99, mean bias = −0.03 ± 0.08, CV% = 3.28, ICC = 0.88, SWC rating: good, p = 0.84) relative to the StopwatchCamera app (r = 0.98, R2 = 0.97, mean bias = −0.11 ± 0.22, CV% = 3.43, ICC = 0.86, SWC rating: marginal, p = 0.10), Analog Stopwatch 1 (r = 0.98, R2 = 0.96, mean bias = −0.09 ± 0.42, CV% = 2.95, ICC = 0.90, SWC rating: good, p = 0.91), and Analog Stopwatch 2 (r = 0.99, R2 = 0.97, mean bias = −0.12 ± 0.88, CV% = 3.51, ICC = 0.87, SWC rating: marginal, p = 0.96). In conclusion, compared to timing gates, the CODTimer app and Seconds Count app provided lower measurement bias and higher sensitivity for assessing CODS performance. © 2023, Termedia Publishing House Ltd.. All rights reserved.