THE RELATIONSHIPS BETWEEN THROWING VELOCITY AND MOTOR ABILITY PARAMETERS OF THE HIGH-PERFORMANCE HANDBALL PLAYERS
AbstractThrowing is one of the basic skills in handball. Two main factors are of importance with regard to the efficiency of shots: accuracy and throwing velocity. The determinants of the ball velocity can be divided into three groups concerning: technique of motion, somatic features and motor ability. Although the technique of motion and the fitness level can be improved by the training process, morphological factors are, in the main part, genetically determined. Since changes in the throwing technique among highperformance players are very small, it was assumed as constant during training process. The aim of the research was to find out the relationships between the linear speed of the ball's flight during different kind of throwing in handball and basic motor ability parameters of players in order to improve the efficiency of training. Twelve highperformance handballers (Polish National Term) took part in the experiment. The average (+SD) values of the body mass, height and age amounted to 89.0+7.8 kg. 1.88 +0.05 m and 23.3 +2.5 years, respectively. The linear ball velocity was measured using a special photocell system during throwing on the spot, with cross-over step and with a jump upwards. Throwing velocity values were related to a maximal muscle strength indicator Mm was evaluated on the basis of the sum of muscle torques developed isometrically by ten main muscle groups: flexors and extensors of elbow, shoulder, knee and hip joints and flexors and extensors of trunk. A special torquemeter device (local make) was employed. The maximal and average mechanical power of the lower extremity and trunk was measured during CMJ performed on a force place (KISTLER).An on-line operating computer (IBM PC) was used to process the force signal. The force-velocity parameters of arm flexion and extension were measured using CES Ariel modified in its mechanical part. Handballers performed STh in the sitting position, propelling the bar of the Arm-Leg Station. The movement was similar to the last phase before the release of the ball during a real throw. Each subject executed 3 kinds of tests: maximal speed diagnostic, isokinetic exercises at angular velocities of 100, 300 and 500 deg/s and isotonic exercises at external torque of 10, 30 and 50 Nxm. Thirty-three parameters were chosen to further the analysis. Result distributions were tested using the Shapiro-Wilk test of normality. A Pearson's correlation matrix was calculated in order to reduce the number of parameters (p50.05). At the next stage, multiple regression analysis was used to estimate relations between tested parameters. Statistically significant contribution of muscle strength (trunk flexors, strength indicator) and maximal forearm speed to the ball velocity has been found.
Coaching and Sports Activities