| Research Purpose:The purpose of the study is to analysis the paddling skill of kayakers by using three-dimensional kinematical measurements. While the technology is in its development stages in other countries, there is almost no record of research on using 3-D measurement techniques to analyze kinematics of aquatic objects in China. By using 3-D and 2-D measurement techniques Synchronization analysis, we can reflect the characteristics of human movements more accurately. We can get the kinematics parameters such as space positions of each steps, shift, time, speed, angle and angle speed while the athletes rowing, pointing out a reasonable paddling technical features of single woman kayak.Methods:This paper uses three SONY DCR-HC1000E video cameras to capture the rowing motion of single women kayakers on a fixed point-fixed focus basis. The athletes are from Zhejiang Province. The capturing frequency is set at 25 frames/s. We use an H-24 3-D DLT stereo radiation structure to calibrate the object. Video analysis is done using the German SIMI0 Motion 7.50 sports movement analysis system. Three-dimensional DLT method was used to analyze.Results:1. From the accuracy of three-dimensional measure of view, there is a big difference in both boat speed and displacement obtained by the two different kinematical analysis. The parameter values of average boat speed and displacement are higher obtained in three-dimensional kinematical analysis than in the two-dimensional analysis.The range of stroke angle which is obtained by two-dimensional kinematical analysis is too large. Three-dimensional kinematical analysis could reflect the actual stroke angle in the range of variation more accurately.There is a big difference between two kinds of analysis of various aspects of the body angles. When rowing on the left side, the body angles are more significant than rowing on the right side. Three-dimensional kinematical analysis could reflect the' stroke angles and body angles more accurately.2. From the characteristics of the boat speed of view, the left side of the various stages of the average boat speed in X direction was higher than the right side, but the right side of the average boat speed are more stability than the left side of the average boat speed. Average boat speed between left and right are very significant. It is attributable to the muscular strength of players are asymmetries. The average boat speed in Y direction indicates that throughout the whole rowing, the boat is a little biased towards the positive direction of Y-axis, that means the boat is coasting towards the right side. The average boat speed in Z direction shows that when athletes are rowing in the pulling phase, the boat head a bit higher than before, and the boat heads back to paddle a downward trend in the stage of the recovery phase. The boat speed difference value in X, Y and Z direction are used to detect the stability of the ship, the smaller the better.3. From the characteristics of displacement of view, the average displacement of the rowing phase are descending as follows:pulling phase>catching phase>later stage of recovery phase>earlier stage of recovery phase. Pulling phase and catching phase are very significant between the left and right phase of rowing. The other phase is not significant at the same time.4. From the characteristics of stroke angle of view, the overall average is closer to both sides of the stroke angle, right angle slightly larger than the left propeller. Critical juncture point of the left and right stroke angle is more uniform. Paddle angle peak appears in the vertical moment, valley appears in the horizontal moment. Propeller angular velocity peak basically appears in the vertical point, the valley appears in the horizontal point. The left propeller angular velocity peaks and valleys appears more unified than the right moment. Right and left propeller angular velocity are almost symmetry. Propeller blade angle and angular velocity was extremely high correlation. the propeller blade angle decrease while the angular velocity increases.5. From the characteristics of body movement and perspective of view, the average angle of the body are descending as follows:elbow angle, shoulder angle, hip angle, trunk angle, shoulder and hip angle, shoulder rotation angle, that means the body angle from the various links to the lower extremities upper extremity is gradually increasing. Activities range from upper "lower extremities" trunk. Homonymy arm paddles the bigger range than the opposite side of the paddle arm. Muscular strength in order:first be made large muscle strength, and then issued by the small muscles strength. In the rowing process, the power transfer from lower limbs to the torso, then passed to the upper torso. The ipsilateral limb movements of rowing are more consistent, different limbs of the rowing movements are less unified. The body movement is a little more asymmetrical. Maximum angular velocity of the homonymy limb appeared earlier than the opposite side of body at all times, that means the homonymy limb rowing limb is pre-emptive force than the opposite side. Fat power bottom-up order is from the same side to the opposite side limbs.6. Correlation between boat speed, displacement, stroke angle and the body angle. Boat speed and displacement has a high degree of correlation in one period of paddling. Boat speed and displacement are the most relevant at the pulling phase. Boat speed and stroke angle has a very high correlation, pulling phase and the earlier stage of recovery phase is of little relevance.The correlation between boat speed and body angle is significant. in which the right elbow joint angle, left and right hip angle, shoulder rotation angle basic with boat speed were positively correlated, the left elbow joint angle, around the shoulder joint angle, trunk angle, shoulder and hip with boat speed was negatively correlated.
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