Jasp software v 0

The Shapiro–Wilk test was used to assess the normality, and Lavene’s test was used for the homogeneity of the data. No violations of normality or homogeneity in the distributions were found (p > 0.05). Descriptive statistics were used for statistical analysis: mean ± standard deviation. Correlations between variables were examined with the Pearson r correlation coefficient, including the coefficient of determination (Pearson’s r squared, R²). The interpretation of the correlations was performed according to Hopkins’ ranking (0.3–0.5 was considered moderate, 0.51–0.70 was considered large, 0.71–0.90 was considered very large, and >0.91 was considered almost perfect) [21 (link)]. Partial correlations were also calculated to exclude the effects of muscle mass and strength on the correlations between echo intensity and fiber type composition. Differences between groups were analyzed with the Student T-Test. Cohen’s d effect size was also calculated (small: 0.2, medium: 0.5, large: 0.8). The level of significance was set at p ≤ 0.05. Reliability for all measurements was assessed using a two-way random-effect intra-class correlation coefficient (ICC). Statistical analysis was performed with JASP software v. 0.18 (University of Amsterdam, The Netherlands).

Descriptive statistics were used for the statistical analysis: mean ± standard deviation. The normality of the data was assessed with the Shapiro–Wilk test, and no violations in normality were observed. The differences before and after the training period were analyzed with Student’s paired-sample t-Test. The Cohen’s d effect sizes were calculated. The correlation between the variables was examined with Pearson’s correlation coefficient. The level of significance was set at p ≤ 0.05. The reliability of all the measurements was tested using a two-way random effect intra-class correlation coefficient (ICC). The statistical analysis was performed with JASP software v. 0.18 (University of Amsterdam, The Netherlands).