KINEMATIC ANALYSIS OF STROKE CYCLE TO AN INTERNATIONAL ATHLETE ON CANOEING -K1

Abstract

INTRODUCTION -The purpose of this study is the cinematic analysis of the strake cycle done on a simulator, by an athlete of the modality with an international curriculum. This analysis has allowed to describe in detail the technique of stroke and its expression on quantitative terms for parameters like: time, velocity, articulated and absolute angles, the trajectory of the whole body centre gravity and of the corporal segments. Bearing the lack of biomechanical studies on this area and the increase of the number of practitioners in Portugal, this knowledge could contribute to a better understanding of the training process. MATERIAL AND METHOD5 -We have analysed one of the most representative athletes of the National Canoe Federation, a 32 year-old men, 90 Kg of weight and 187 cm of height. We used the video camera to "catch" the strake cycle during a training session. After this we have analysed the cinematic parameters, using a bidimensional computer programme "Peak Performance 5 -Motion measurement system" from Peak Performance Technologies, Inc.. RE5ULT5 -We verified small oscillations of the centre of gravity (c. g.) on the sagital plane (x =4 cm and y =3,5 cm) during the strake cycle. The horizontal velocity (vx) of the left hand was analysed, having its maximum values at the vertical position of the paddle: Vx (aerial, phase) = 2,1 m/s; Vx (aquatic phase) = 1,1 m/s. The zero values of Vx were found in the horizontal position of the paddle. On the other hand, vertical velocity (vy) reaches its maximum at the horizontal position of the paddle and was zero when the paddle is vertical. Analysing the angle of the segment trunk (defined by the shoulder and hip) in relation to the vertical axis, we observed a variation of 25,8° The angle corresponding to the shoulder forward inclination was 14,7° and the angle corresponding to the backward inclination was 11,1 ° The knee angle showed for the maximal extension and flexion of the leg was 163,3° and 129,7°, respectively The maximal and minimal ankle angles were 89,7° and 134,6° CONCLU510NS -The c.g. movement in sagital plane can cause smooth rotations of the kayak in real conditions. There is a relation between the knee and ankle angles, which is, the extension of the knee is related to the ankle plantar flexion and the flexion of the knee is related to the ankle dorsal flexion. As it is in the aquatic phase that one founds the maximum values for horizontal velocity (the paddle is vertical) it seems that the simulator offers a great relation between the horizontal velocity and the propulsion of the kayak. This investigation should contribute to an improvement of the training process specially in technique, because it allows a comparison between the simulate situation and real situation.