Artículos de Investigación

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    Item type:Publication,
    Effects of Knee Sleeve Density on Theoretical Neuromuscular Capacities Derived from the Force–Velocity–Power Profile in the Back Squat
    (2026)
    Jorge Leschot-Gatica
    ;
    Luis Romero-Vera
    ;
    Alberto Ñancupil-Andrade
    ;
    Claudio Hernández-Mosqueira
    ;
    Iván Molina-Márquez
    <jats:p>Background: Neoprene knee sleeves are commonly used to enhance joint stability and mechanical performance during resistance training. However, the specific influence of sleeve density on the force–velocity–power (F–V–P) profile during multi-joint lower-body exercises such as the back squat remains unclear. This study aimed to compare the theoretical F–V–P parameters derived from back squat performance while wearing low-density (LD) versus high-density (HD) knee sleeves. Methods: Fifteen resistance-trained males completed an incremental back squat test under both LD and HD conditions. A linear position transducer recorded barbell displacement and velocity. Individual force–velocity relationships were modelled to determine maximal theoretical force (F0), velocity (V0), power (Pmax), and the F–V slope. Paired-sample t-tests, linear mixed models, and Cohen’s d effect sizes were calculated. Clinical relevance was assessed using a threshold defined as 0.2 × the standard deviation of the HD condition. Bayesian analyses were conducted to estimate the probability and magnitude of the observed effects. Results: No statistically significant differences were observed between sleeve conditions for F0, V0, Pmax, or F–V slope (p &gt; 0.05, d ≤ 0.37). Nonetheless, HD sleeves yielded slightly higher mean values for F0, V0, and Pmax, exceeding the predefined threshold for practical relevance. Bayesian models showed moderate probabilities (~0.80) that HD sleeves outperformed LD, though with limited chances of crossing the clinical significance threshold. Conclusions: Although HD sleeves do not produce systematic changes in F–V–P parameters, their increased material stiffness may provide small yet practically meaningful mechanical advantages in high-force resistance training contexts.</jats:p>
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    Item type:Publication,
    Different Shoulder Exercises Affect the Activation of Deltoid Portions in Resistance-Trained Individuals
    (2020)
    Yuri A. C. Campos
    ;
    Jeferson M. Vianna
    ;
    Miller P. Guimarães
    ;
    Jorge L. D. Oliveira
    ;
    Claudio Hernández-Mosqueira
    <jats:title>Abstract</jats:title> <jats:p>The aims of this study were to compare muscle activity of the anterior deltoid, medial deltoid, and posterior deltoid in the bench press, dumbbell fly, shoulder press, and lateral raise exercises. Thirteen men experienced in strength training volunteered for the study. Muscle activation was recorded during maximum isometric voluntary contraction (MVIC) for data normalization, and during one set of 12 repetitions with the load of 60% 1RM in all exercises proposed. One-way repeated-measures ANOVA with Bonferroni’s posthoc was applied using a 5% significance level. For anterior deltoid, the shoulder press (33.3% MVIC) presented a significantly higher level of activation when compared to other exercises. Also, no significant difference was found between the bench press (21.4% MVIC), lateral raise (21.2% MVIC), and dumbbell fly (18.8% MVIC). For the medial deltoid, the lateral raise (30.3% MVIC) and shoulder press (27.9% MVIC) presented a significantly higher level of activity than the bench press (5% MVIC) and dumbbell fly (3.4% MVIC). Besides, no significant difference was found between the bench press and the dumbbell fly. For the posterior deltoid, the lateral raise (24% MVIC) presented a significantly higher level of activation when compared to other exercises. For the posterior deltoid portion, the shoulder press (11.4% MVIC) was significantly more active than the bench press (3.5% MVIC) and dumbbell fly (2.5% MVIC). Moreover, no significant difference was found between the bench press and the dumbbell fly. In conclusion, the shoulder press and lateral raise exercises showed a higher level of muscle activation in the anterior deltoid and medial deltoid when compared to the bench press and dumbbell fly exercises.</jats:p>
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    Item type:Publication,
    Effect of neuromuscular resistance training on the performance of 5-km runners
    (2020)
    Miller P. Guimarães
    ;
    Yuri A.C. Campos
    ;
    Hiago L.R. de Souza
    ;
    Gaspar P. da Silva
    ;
    Claudio Hernández-Mosqueira
    <jats:p>The study aimed to identify the effect of a neuromuscular resistance training protocol (NRTP) on the performance of 5-km distance runners. This study included 18 male runners (age=29.3±3.2 years, fat percentage=11.3±2.6%, body height=1.77±.04 m, body mass=73.4±4.4 kg, time in 5 km=20.6±2.4 min, training years=4.3±0.7 years). First, volunteers were anthropometrically evaluated, and they performed one-repetition maximum (1RM) 45º leg press (LP) strength test. Second, they performed an incremental protocol in the 45º LP to acquire the electromyographic threshold. Third, they completed a 5-km time trial run (5 km basal). In the fourth session, they performed NRTP in LP. And fifth, the 5-km time trial run was performed at 30 min, 48 h, 96 h, and 144 h post the NRTP intervention. A significant decrease (p≤.05) was observed when baseline values were compared with post 30 min and post 48 h (p=.02 and p=.04, respectively). However, there were significant positive differences in performance (p=.04 for time) when baseline values and post 144 h were analyzed. Therefore, it is concluded that the NRTP can be used by 5-km distance runners to improve their performance with a break of one week between the intervention and test.</jats:p>