## 3 Results  
No significant differences were found (\(p\) > 0.05), and null ES (ES \(<\) 0.14) were detected in the measures of maximum muscle strength in the right and left knee extensors and flexors in their concentric or eccentric phases. In the test-retest reliability measures, acceptable absolute reliability and extremely high relative reliability were obtained for all peak muscle strength assessments, as presented in Table 1.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **Mean \(\pm\) SD (N)** & \(p\)**-Value** & **ES** & **SEM** & **CV\%** & **ICC** \\ \hline \hline  & **Test** & **Retest** & & **(95\% CI)** & **(95\% CI)** & **(95\% CI)** \\ \hline Right knee extension & & & & & & \\ \hline Concentric & 175.07 \(\pm\) 63.99 & 171.24 \(\pm\) 56.59 & 0.43 & 0.06 & 14.85 & 8.13 & 0.95 \\  & & & & (10.87–23.42) & (6.06–12.37) & (0.85–0.98) \\  & & & & 24.59 & 13.34 & 0.85 \\  & & & & (25.76–52.65) & (6.67–13.97) & (0.64–0.94) \\ \hline Left knee extension & & & & & & \\ \hline Concentric & 159.33 \(\pm\) 50.17 & 165.31 \(\pm\) 47.96 & 0.29 & 0.12 & 16.17 & 9.96 & 0.90 \\  & & & & (12.04–24.60) & (7.42–15.16) & (0.76–0.96) \\  & & & & 18.89 & 7.18 & 0.97 \\  & & & & (14.07–28.74) & (5.35–10.92) & (0.91–0.99) \\ \hline Right knee flexion & & & & & & \\ \hline Concentric & 86.69 \(\pm\) 25.17 & 89.57 \(\pm\) 24.57 & 0.21 & 0.11 & 6.51 & 7.39 & 0.94 \\  & & & & (4.85–9.91) & (5.50–11.24) & (0.85–0.98) \\  & & & & 14.62 & 8.65 & 0.93 \\  & & & & (10.89–22.25) & (5.35–13.16) & (0.81–0.97) \\ \hline Left knee flexion & & & & & & \\ \hline Concentric & 87.46 \(\pm\) 30.45 & 91.76 \(\pm\) 29.98 & 0.17 & 0.14 & 8.88 & 9.91 & 0.92 \\  & & & & (6.61–13.52) & (7.38–15.08) & (0.80–0.97) \\  & & & & 16.05 & 9.65 & 0.91 \\  & & & & (11.95–24.42) & (7.19–14.69) & (0.77–0.97) \\ \hline \hline  & & & & & & \\ \end{tabular}  
N: newton; \(p\)-value: significance level; SD: standard deviation; ES: Cohen’s d effect size; SEM: standard error of measurement; CV%: coefficient of variation; ICC: intraclass correlation coefficient; 95% CI: 95% confidence interval; s: seconds.  
\end{table}
Table 1: Evaluation of peak force in extension and flexion of the right knee in the concentric and eccentric phases.  
The Bland-Altman plots reveal a low systematic bias (\(-\)15.43-3.825 N) for the assessment of peak muscle strength in right knee extension (RKE), peak muscle strength in left knee extension (LKE), peak muscle strength in right knee flexion (RKF), and peak muscle strength in left knee flexion (LKF) in the concentric and eccentric phase, as well as a coefficient of determination of R\({}^{2}\) = 0.223\(-\)0.018, as shown in Figure 3.  
Figure 3: Bland–Altman plots of test–retest for peak muscle strength in right knee extension (RKE), peak muscle strength in left knee extension (LKE), peak muscle strength in right knee flexion (RKF), and peak muscle strength in left knee flexion (LKF) in the concentric and eccentric phases in both test sessions during maximal muscle strength assessment using a FEMD.  
The magnitude r was almost perfect (0.926) for RKE and very large for LKE, RKF, and LKF (0.756-0.848) in the concentric phase. In the eccentric phase, the magnitude r was almost perfect for RKE and KLE (0.901-0.941) and very large for RKF and LKF (0.779-0.826), and all results were highly significant (\(p\) = 0.001), as can be seen in Figure 4.  
Figure 4: Cont.