Comparison of Hamstring Extensibility and Spinal Posture between Kayakers and Canoeists

The aims of this study were: 1) to determine the differences in hamstring extensibility between kneeling and forward legs in a group of canoeists; 2) to compare hamstring extensibility between canoeists and kayakers; and 3) to compare the sagittal spinal posture and pelvic tilt in the maximal trunk flexion with knees extended in kayakers and canoeists. Ninety-nine young male paddlers (17.51±6.15 years) (35 kayakers, 35 right-side canoeists and 29 left-side canoeists) participated in this study. Hamstring muscle extensibility was determined in both legs throughout the passive straight-leg raise test (PSLR) and the sit-and-reach test. Sagittal spinal curvatures and pelvic tilt were measured in the maximal trunk flexion with knees extended (sit-and-reach test) using a Spinal Mouse. The hamstring extensibility of the forward leg was higher than the kneeling leg ones in both groups of canoeists (p<.001). No significant differences were found between the right and left legs in kayakers. The kayakers showed the highest values in PSLR, sit-and-reach test, lumbar angle and pelvic tilt, whereas the canoeists obtained the lowest values in the thoracic angle. There were no significant differences between the canoeists who paddle on the left and those that paddle on the right side of the canoe either in the spinal or in the pelvic postures. In conclusion, the asymmetric movement of canoeing is associated with differences in hamstring extensibility between the kneeling and forward legs. The canoeists showed higher extensibility in the forward leg than in the kneeling leg. Furthermore, a greater hamstring extensibility is associated with a lower thoracic angle and higher lumbar flexion and pelvic tilt in the sit-and-reach test.