Purpose: This study investigates bilateral performance with the Special Judo Fitness Test (SJFT) and its associations with competition performance (CP) and competition volume (CV) in judo. Methods: The SJFT compared movement patterns of the dominant (D) and nondominant (ND) sides on a sample of 27 youth judoka. Repeated-measures analysis of variance was used to determine differences in SJFT execution to the D and ND side, and for associations, the Pearson correlation was used (P < .05). Results: The total number of throws is significantly higher on the D side, with better performance in the final SJFT index. The CP showed positive correlations with the D side of SJFT executions in the second part of SJFT (P = .042) and the total number of throws (P = .036). On the ND side, the CP showed a positive correlation with the second part of the SJFT (P = .014), a negative correlation with the third part of the SJFT (P = .035), and a positive correlation in the total number of throws (P = .027). CV shows significant correlations with all parameters of the SJFT in the D and ND sides, with stronger correlations on the ND side. Conclusions: The study presents significantly better performance in judokas’ D side in SJFT. Associations between CP and CV with the SJFT were significant in connection to both body sides. It highlights the importance of bilateral movement development and good execution of the throwing techniques for the D and ND body sides of youth judoka to achieve greater CP all year round.
Jožef Šimenko and Vedran Hadžić
Darjan Spudić, Janez Vodičar, Miha Vodičar, and Vedran Hadžić
Context: The importance of isometric trunk strength (ITS) among sport science professionals is higher than its actual reported effect size on either performance or low back pain (LBP) occurrence. Objective: To provide normative values of ITS and strength ratios, and to evaluate the effect of sex, sports discipline, and LBP status. Design: Crossover study. Setting: University research laboratory. Participants: Five hundred and sixty-seven elite athletes (186 females) with and without a history of LBP from different sports. Main Outcome Measure: Participants underwent ITS testing for trunk flexors, extensors, and lateral flexors. Normalized maximal strength (in newton meter per kilogram) and strength ratios were calculated. Differences between sex, LBP, and sport disciplines were assessed with 3-way analysis of variance (sex × LBP status × 7 sport categories) and partial eta-squared (