Andrzej Mastalerz
Jozef Pilsudski University of Physical Education in Warsaw, Poland

Throwing events in track and field (shot put, hammer throw, javelin throw and discus throw) have been the subject of a number of studies (Ariel, 1979; Bartonietz, 1996). Good performance in these track and field events is mainly determined by the athlete's technique rather than tactics. Release parameters, i.e. height of release, angle of release and release velocity have been the parameters generally analyzed in the studies on throwing events such as shot put.). The correlation between release velocity and the measured distance is very strong. Release speed is also inversely proportional to the angle of release (Hubbard et al., 2001). According to the classification of physical performance tests suggested by Hopkins et al. (2001), the jumping and throwing tasks fell under the category of the iso-inertial tests. Amongst the trials performed by the same athlete, the performance can vary substantially. Also, in some trials, the athletes fail (they break the rules) and the performance is discarded. We will call the percentage of successful trials the athlete’s dependability.
Objective of the study was, according to average relative error, to analyze the variability of biomechanical indicators (of athletes and the put) during shot put for the athletes of international level (8 athletes – group A) and for the athletes of national level (6 athletes – group B).
Methods and structure of the study. Each of the athletes performed 6 trials and all videos were collected using two high speed digital cameras placed on the performance field, perpendicular to each other. Only measured trials were analyzed using three dimensional APAS software.
Results and conclusions. According to the average relative error, selected indicators of the athlete and the put (mainly during release) have generally shown low variability (below 10% in about 80% of the analyzed cases). In only 4 out of analyzed cases (for two release indicators) variability was high (>20%), in 9 of cases variability (according to the average relative error) was medium (10%-20%), while in the remaining cases variability was low (<10%).

Keywords: throwing, biomechanical parameters, 3D kinematic analysis.

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