## 3 Results  
Significant differences were found in body mass and trochanterion-tibiale laterale length, in PSLR and ASLR tests, and in pelvic tilt in attack position in the kayak between the three groups, with a low to moderate size effect. There were no significant differences in the other variables (Tables 1 and 2). Figure 1: Measurements of the equipment. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Variable** & **Olympics (n = 8)** & **U-23 (n = 13)** & **Amateur (n = 13)** & **F and \(p\) Value** \\ \hline Age (years-old) & \(25.7\pm 3.8\) & \(18.8\pm 1.5\) & \(21.6\pm 3.4\) & F = \(14.032;p<0.001\) \\ Body Mass (kg) & \(87.1\pm 7.4\) & \(76.8\pm 6.9\) & \(74.2\pm 6.8\) & F = \(8.808;p=0.001\) \\ Height (cm) & \(184.8\pm 4.55\) & \(179.1\pm 5.2\) & \(180.4\pm 7.2\) & F = \(2.369;p=0.119\) \\ Iliosipnela H (cm) & \(102.7\pm 2.7\) & \(98.5\pm 3.3\) & \(100.2\pm 5.6\) & F = \(2.320;p=0.114\) \\ Trochanterior-tibiale & \(48.7\pm 2.0\) & \(45.4\pm 2.7\) & \(46.1\pm 3.0\) & F = \(3.932;p=0.035\) \\ laterale L (cm) & \(48.3\pm 1.3\) & \(46.4\pm 2.3\) & \(47.4\pm 2.60\) & F = \(1.992;p=0.154\) \\ Foot L (cm) & \(28.2\pm 1.4\) & \(27.00\pm 1.0\) & \(27.0\pm 1.2\) & F = \(3.267;p=0.052\) \\ SL R Right Passive (\({}^{\circ}\)) & \(91.5\pm 11.1\) & \(85.6\pm 9.3\) & \(94.6\pm 7.6\) & F = \(3.223;p=0.053\) \\ SLR Left Passive (\({}^{\circ}\)) & \(90.4\pm 11.7\) & \(82.8\pm 8.7\) & \(94.2\pm 8.5\) & F = \(4.915;p=0.014\) \\ SLR Right Active (\({}^{\circ}\)) & \(71.0\pm 13.4\) & \(72.3\pm 8.6\) & \(82.1\pm 6.6\) & F = \(4.979;p=0.013\) \\ SLR Left Active (\({}^{\circ}\)) & \(72.6\pm 12.9\) & \(71.1\pm 7.0\) & \(80.6\pm 8.5\) & F = \(3.868;p=0.032\) \\ Thoracic curv. Strand (\({}^{\circ}\)) & \(53.1\pm 9.3\) & \(50.5\pm 3.6\) & \(47.6\pm 9.6\) & F = \(1.302;p=0.287\) \\ Lumbar curv. Stand (\({}^{\circ}\)) & \(-24.4\pm 7.5\) & \(-22.8\pm 7.2\) & \(-26.5\pm 4.8\) & F = \(1.007;p=0.355\) \\ Pelvic tilt Stand (\({}^{\circ}\)) & \(9.7\pm 4.1\) & \(10.9\pm 5.8\) & \(14.5\pm 4.4\) & F = \(2.77;p=0.078\) \\ Thoracic curv. BP (\({}^{\circ}\)) & \(33.4\pm 9.7\) & \(36.0\pm 8.2\) & \(34.5\pm 9.4\) & F = \(0.219;p=0.804\) \\ Lumbar curv. BP (\({}^{\circ}\)) & \(20.0\pm 6.5\) & \(20.6\pm 7.7\) & \(16.1\pm 7.2\) & F = \(1.432;p=0.254\) \\ Pelvic tilt BP (\({}^{\circ}\)) & \(-8.0\pm 4.8\) & \(-9.4\pm 6.4\) & \(-6.1\pm 5.9\) & F = \(0.976;p=0.388\) \\ Thoracic curv. AP Right (\({}^{\circ}\)) & \(33.9\pm 10.2\) & \(37.7\pm 7.7\) & \(32.8\pm 11.4\) & F = \(0.844;p=0.448\) \\ Lumbar curv. AP Right (\({}^{\circ}\)) & \(23.9\pm 7.0\) & \(29.0\pm 6.6\) & \(26.5\pm 7.2\) & F = \(1.377;p=0.267\) \\ Pelvic tilt AP Right (\({}^{\circ}\)) & \(-1.7\pm 4.0\) & \(0.3\pm 6.5\) & \(10.8\pm 7.4\) & F = \(12.799;p<0.001\) \\ Thoracic curv. AP Left (\({}^{\circ}\)) & \(34.7\pm 9.6\) & \(34.3\pm 8.1\) & \(29.8\pm 12.3\) & F = \(0.857;p=0.434\) \\ Lumbar curv. AP Left (\({}^{\circ}\)) & \(22.5\pm 9.5\) & \(32.2\pm 7.3\) & \(27.9\pm 5.7\) & F = \(4.392;p=0.021\) \\ Pelvic tilt AP Left (\({}^{\circ}\)) & \(-2.6\pm 6.1\) & \(0.7\pm 5.4\) & \(11.5\pm 6.4\) & F = \(16.997;p<0.001\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Anthropometric characteristics, hamstring extensibility, and sagittal spinal curvatures of the different groups of kayakers (mean \(\pm\) standard deviation).