## 3 Results
### Intra-Session Reliability in Isometric Belt Squat Test  
Descriptive statistics for the variables analyzed during the first session of IBSqT measurements are shown in Table 2. PF and RPF have demonstrated excellent reliability values for IBSqT (0.95-0.97) and acceptable variability with CV \(\leq\) 10% (Table 2). The variable force at 50 ms (ICC = 0.89) shows acceptable variability (CV = 9.6%); however, as the time window for this variable increases, the results tend to become more dispersed with CV >10%. RFD across all its time windows shows good to excellent ICC values, but none of the variables meet the acceptable variability criterion of CV \(\leq\) 10%. For impulse (IMP), all time windows demonstrated ICC values ranging from good to excellent with CV \(\leq\) 10%, except for IMP0-150 (ICC = 0.79; CV = 14.5%). Furthermore, RPF showed good sensitivity to performance changes, as SWC0.2 scored higher than SEM. \begin{table}
\begin{tabular}{c c c c c c c} \hline  & **Mean** & **SD** & **CV\% (95\%CD)** & **ICC (95\%CD)** & **SEM (95\%CD)** & **SWC (0.2 (95\%CD)** \\ \hline Peak force (N) & 2964.7 & 756.5 & 4.2 (3.4-5.7) & 0.98 (0.95-0.99) & 126.0 (1013-168.0) & 149.2 (85.1-190.9) \\ Relative peak force (N/kg) & 37.6 & 11.3 & 4.3 (3.4-5.7) & 0.98 (0.96-0.99) & 1.6 (1.3-2.1) & 2.2 (1.3-2.9) \\ Force at 50 ms (N) & 1391.8 & 376.0 & 13.4 (10.7-17.8) & 0.77 (0.58-0.89) & 186.0 (149.6-248.0) & 65.4 (42.1-88.0) \\ RFD 0-50 ms (N-s) & 5756.5 & 4808.5 & 32.6 (26.2-43.5) & 0.86 (7.02-0.93) & 1878.3 (5107-2505.1) & 885.3 (539.5-1164.0) \\ Impulse 0-50 ms (N-s) & 61274.9 & 1386.67 & 11.8 (9.5-15.7) & 0.74 (0.53-0.87) & 726.1 (5804.0-4685.3) & 2863.1 (549.5-3206.6) \\ Force at 100 ms (N) & 1669.3 & 535.4 & 15.8 (12.7-21.1) & 0.77 (0.58-0.89) & 264.5 (212.7-352.8) & 93.1 (59.9-125.3) \\ RFD 0-100 ms (N-s) & 5786.0 & 3933.9 & 26.5 (23.1-35.3) & 0.86 (7.03-0.93) & 1535.3 (1233.4-2045.3) & 72.5 (441.6-952.5) \\ Impulse 0-100 ms (N-s) & 13863.6 & 358.75 & 10.3 (10.5-17.4) & 0.76 (0.56-0.88) & 1807.09 (14354.2-2410.23) & 6198.1 (4013.8-86.0) \\ Force at 150 ms (N) & 1858.9 & 614.0 & 18.1 (45.2-4.1) & 0.72 (0.49-0.86) & 335.9 (2702.4-448.0) & 102.0 (868.6-140.0) \\ RFD 0-150 ms (N-s) & 4668.7 & 2471.8 & 330.6 (25.4-4.0) & 0.63 (0.73-0.81) & 1540.9 (1293.3-2055.2) & 386.5 (274.6-54.1) \\ Impulse 0-150 ms (N-s) & 2256.61 & 6387.9 & 14.3 (11.9-19.4) & 0.76 (0.56-0.88) & 324.3 (2601.7-443.12) & 11.0 (5746.2-1488.83) \\ Force at 200 ms (N) & 2074.3 & 672.4 & 18.9 (15.2-25.2) & 0.68 (0.44-0.84) & 391.2 (3146.2-5218) & 109.4 (749.1-51.5) \\ RFD 0-200 ms (N-s) & 5253.1 & 2253.1 & 27.3 (21.9-36.4) & 0.70 (0.46-0.85) & 1433.4 (11529.1-1911.8) & 415.3 (281.4-572.4) \\ Impulse 0-200 ms (N-s) & 3323,426 & 959.09 & 15.5 (12.5-20.7) & 0.74 (0.52-0.87) & 502.81.7 (0.44-0.67-063.8) & 16.143.8 (0.62-0.195.47) \\ Force at 250 ms (N) & 2214.8 & 661.1 & 16.5 (13.3-22.1) & 0.71 (0.48-0.85) & 366.2 (294.5-488.4) & 110.1 (38.1-51.0) \\ RFD 0-250 ms (N-s) & 4636.4 & 1970.8 & 16.6 (0.33-22.1) & 0.86 (0.73-0.93) & 767.4 (617.2-102.5) & 363.1 (221.4-477.2) \\ Impulse 0-250 ms (N-s) & 431,115.5 & 127,627.6 & 1.59 (12.8-21.2) & 0.73 (0.51-0.86) & 65,588.7 (55,164.9-914.80) & 215,256.2 (425.1-2955.9) \\ \hline \end{tabular}
\end{table} 
Table 1: Intra-session reliability of DMTP.