Angular Changes in the Elbow Joint During Underwater Movement in Synchronized Swimmers

The aim of the study was to analyze the changes in the projection of the angle between arm and forearm in one cycle of supporting movement of upper limbs in the Vertical and Vertical Bent Knee positions in synchronised swimmers of various sports level. The research material consisted of eight swimmers, three seniors and five juniors. The study was performed using an underwater camera and acomputer software. The frequency of images was 50 frames per second. The angular progress of the studied movements in swimmers representing lower level was compared to that of swimmers with higher sport achievements. The duration of phases making up one movement cycle was specified. The scope of angular changes in the joint was calculated as well as the duration of individual phases in one movement cycle, angular velocity of movement in individual phases of the cycle and the degree of asymmetry of the studied movement between left and right limbs was assessed. The course of movement with its phases in the Vertical position was compared with that in the Vertical Bent Knee position. The results of the study made it possible to note the phenomena unnoticed by coaches carrying out visual observation. The most important ones are omitting, also by experienced swimmers, the phase of water catch, asignificant diversity in the course of phase of preparation in terms of symmetry and angular values, large differences in this phase of movement between the Vertical and Vertical Bent Knee positions and low angular velocity in experienced swimmers.