Examinando por Autor "Tuesta-Roa, Marcelo"

Mostrando 1 - 2 de 2
  • No hay miniatura disponible
    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, Eduardo
    In 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.
  • Miniatura
    Ítem
    Dynamometric Strength Profile of Hip Muscles in Youth Soccer Players
    (MDPI, 2023-01) Contreras-Díaz, Guido; Chirosa-Ríos, Luis Javier; Riego-Ruiz, Antonio; Intelangelo, Leonardo; Tuesta-Roa, Marcelo; Morales-Zúñiga, Jorge; Jerez-Mayorga, Daniel
    Background: Soccer is the most widely practiced sport in the world, demanding high-speed activities such as jumps, sprints and changes of direction. Therefore, having optimal levels of muscle strength improves performance and reduces the injury rate. Objectives: The objectives of our study were (i) to determine the dynamometric profile of hip muscle strength in young soccer players by position, evaluated at different isokinetic speeds, (ii) to describe the conventional and functional unilateral muscle strength ratios, (iii) to analyze the bilateral balance. Methods: Thirty-seven male soccer players (age 17.02 ± 0.92 years) participated in the study. Strength assessment was performed with a functional electromechanical dynamometer, and concentric and eccentric strength of abductors, adductors, extensors and hip flexors were measured bilaterally at 0.5 m/s and 1 m/s. Results: For eccentric right hip abduction at 0.5 m/s, defenders are significantly stronger than midfielders (p = 0.013) and stronger than forwards (p = 0.140). For eccentric right hip adduction at 0.5 m/s, defenders are significantly stronger than midfielders (p = 0.005) and stronger than forwards (p = 0.253), as for eccentric right hip adduction at 1 m/s, defenders are significantly stronger than midfielders (p = 0.014) and stronger than forwards (p = 0.084). There is a significant effect for the conventional strength ratio of left abduction/adduction at 1 m/s. The conventional strength ratio of forwards is significantly higher than that of defenders (p = 0.045) and higher than that of midfielders (p = 0.152). Conclusions: Concentric and eccentric hip strength values differ according to playing position. © 2023 by the authors.