## 3 Results
\begin{table}
\begin{tabular}{c c c c c c} \hline  & **Test** & **Retest** & **ICC (95\% CI)** & **TE (95\% CI)** & **CV\% (95\% CI)** & **MDC (95\% CI)** \\ \hline Hamstring strength & & & & & \\
**MVIC (N)** & & & & & \\ Dominant leg & 344 \(\pm\) 93 & 362 \(\pm\) 93 & 0.88 (0.72, 0.95) & 34 (25, 50) & 9.6 (7.1, 14.1) & 94 (69, 139) \\ Non-dominant leg & 334 \(\pm\) 94 & 331 \(\pm\) 91 & 0.90 (0.77, 0.96) & 30 (22, 44) & 9.1 (6.6, 13.2) & 83 (61, 122) \\
**RFD\({}_{\textbf{max}}\) (N-s\({}^{\textbf{-1}}\))** & & & & & \\ Dominant leg & 1435 \(\pm\) 696 & 1340 \(\pm\) 695 & 0.75 (0.45, 0.89) & 366 (276, 541) & 26.3 (19.9, 39) & 1014 (765, 1500) \\ Non-dominant leg & 1415 \(\pm\) 753 & 1201 \(\pm\) 629 & 0.59 (0.19, 0.82) & 459 (347, 680) & 35.1 (26.5, 52) & 1274 (962, 1885) \\
**RFD\({}_{\textbf{0-50}}\) (N-s\({}^{\textbf{-1}}\))** & & & & & \\ Dominant leg & 1313 \(\pm\) 963 & 1139 \(\pm\) 791 & 0.84 (0.62, 0.93) & 375 (283, 555) & 30.6 (23.1, 45.3) & 1041 (784, 1538) \\ Non-dominant leg & 1285 \(\pm\) 940 & 1465 \(\pm\) 910 & 0.87 (0.70, 0.95) & 350 (264, 517) & 25.4 (19.2, 37.6) & 970 (732, 1433) \\
**RFD\({}_{\textbf{-150}}\) (N-s\({}^{\textbf{-1}}\))** & & & & & \\ Dominant leg & 1017 \(\pm\) 608 & 902 \(\pm\) 493 & 0.80 (0.56, 0.92) & 257 (194, 381) & 26.8 (20.2, 39.7) & 714 (538, 1056) \\ Non-dominant leg & 965 \(\pm\) 584 & 1088 \(\pm\) 551 & 0.86 (0.68, 0.94) & 222 (168, 329) & 21.6 (16.4, 32.1) & 616 (466, 912) \\
**RFD\({}_{\textbf{0-250}}\) (N-s\({}^{\textbf{-1}}\))** & & & & & \\ Dominant leg & 746 \(\pm\) 338 & 824 \(\pm\) 421 & 0.78 (0.52, 0.91) & 185 (140, 274) & 23.6 (17.8, 34.9) & 515 (388, 759) \\ Non-dominant leg & 857 \(\pm\) 376 & 769 \(\pm\) 401 & 0.84 (0.64, 0.94) & 162 (122, 240) & 19.9 (15.0, 29.5) & 450 (338, 665) \\ QuadricGPS strength & & & & & \\
**MVIC (N)** & & & & & \\ Dominant leg & 252 \(\pm\) 76 & 245 \(\pm\) 62 & 0.90 (0.76, 0.96) & 23 (18, 34) & 9.3 (11.3, 13.7) & 64 (50,94) \\ Non-dominant leg & 239 \(\pm\)73 & 250 \(\pm\) 69 & 0.80 (0.55, 0.92) & 33 (25, 49) & 13.5 (10.2, 20) & 92 (69, 136) \\
**RFD\({}_{\textbf{max}}\) (N-s\({}^{\textbf{-1}}\))** & & & & & \\ Dominant leg & 1919 \(\pm\) 755 & 2081 \(\pm\) 796 & 0.66 (0.30, 0.85) & 470 (355, 695) & 23.5 (17.8, 34.8) & 1304 (984, 1926) \\ Non-dominant leg & 2013 \(\pm\) 886 & 1926 \(\pm\) 792 & 0.92 (0.80, 0.97) & 256 (193, 378) & 13.0 (9.8, 19.2) & 710 (535, 1048) \\
**RFD\({}_{\textbf{0-50}}\) (N-s\({}^{\textbf{-1}}\))** & & & & & \\ Dominant leg & 1707 \(\pm\) 844 & 1529 \(\pm\) 747 & 0.62 (0.25, 0.84) & 505 (381, 746) & 31.1 (23.5, 46.1) & 1399 (1056, 2068) \\ Non-dominant leg & 1739 \(\pm\) 1020 & 1427 \(\pm\) 853 & 0.73 (0.43, 0.89) & 505 (382, 747) & 31.9 (24.1, 47.2) & 1400 (1059, 2071) \\
**RFD\({}_{\textbf{-150}}\) (N-s\({}^{\textbf{-1}}\))** & & & & & \\ Dominant leg & 985 \(\pm\) 335 & 1089 \(\pm\) 450 & 0.72 (0.41, 0.88) & 217 (164, 321) & 20.9 (15.8, 31.0) & 603 (455, 890) \\ Non-dominant leg & 891 \(\pm\) 312 & 1034 \(\pm\) 467 & 0.61 (0.22, 0.83) & 257 (194, 380) & 26.9 (20.2, 39.5) & 712 (538, 1053) \\
**RFD\({}_{\textbf{0-250}}\) (N-s\({}^{\textbf{-1}}\))** & & & & & \\ Dominant leg & 794 \(\pm\) 303 & 730 \(\pm\) 213 & 0.78 (0.51, 0.91) & 129 (98, 191) & 17.0 (13, 25.1) & 359 (272, 529) \\ Non-dominant leg & 739 \(\pm\) 300 & 676 \(\pm\) 213 & 0.70 (0.37, 0.87) & 147 (111, 218) & 20.9 (15.7, 30.8) & 410 (308, 604) \\ \hline \end{tabular}
\end{table} 
Table 1: Reliability of isometric hamstring and quadriceps strength measured through a field-based test in football players. Figure 2: (**A**–**E**) Bland–Altman plots show the bias (test-retest differences) for the isometric hamstring strength test. Shadows are limits of agreement (LoA) for dominant (green, clear) and non-dominant (red, dark) legs. Figure 3: (**A–E**) [PERSON]–Altman plots show the bias (test-retest differences) for the isometric quadriceps strength test. Shadows are limits of agreement (LoA) for dominant (green, clear) and non-dominant (red, dark) legs.