The purpose of the study was to examine the consistency and variability of kinematical parameters in the technique used in the triple jump, one of the most complex athletics disciplines. An examination was made of two attempts of an elite female jumper that were performed in laboratory conditions during her preparation for the 2008 Olympic Games, where she placed 6th in the final. The Opto-track system and 3-D kinematical technology were used to study the parameters of model technique. The analysis revealed that optimal results can be achieved with different programme motor strategies and that the motor pattern is generated by consistent and variable parameters. The most consistent parameters of motor pattern in the subject were: partial distances of the individual phases, duration of the support phases in the take-off actions, the angles of take-off and the vertical amplitude of the body centre of mass. Variability of the motor pattern was revealed mostly in the following kinematical parameters: the velocity in the last 5m of the approach, the length and proportion of the last two approach strides, the horizontal velocity of the body centre of mass in the take-off actions. The triple jump is a complex track and field discipline in which the result depends on a combination of speed, strength, technique and visual and kinaesthetic movement control. Optimal integration of cyclic and acyclic movements ensures maximal efficiency of the motor pattern. However, the motor pattern is not always consistent. Some technical elements of the model are consistent, whereas the others vary. The purpose of the study was to find out if a female athlete at the highest international level uses different programme strategies when executing the triple jump, which of the kinematical parameters vary, and which are consistent. With the use of 3-D biomechanical analysis of two attempts, the following conclusions can be made: • the approach velocity in the last five metres (6 - 1 m) varied significantly; • the distance and proportion of the last two approach strides varied and the visual control of the subject was not optimal; • the kinematical structure of the approach revealed the subject had a tendency towards a longer last stride and shorter penultimate stride; • the velocity of the last two strides (L2 + L1) was different; • the subject achieved the highest approach velocity in the last stride; • partial distances of the jump phases (hop-step-jump) were relatively stable with the distance of step varying the most; • in both attempts the subject used a strategy of preserving the horizontal velocity with emphasis on the distance of the last phase; • the subject is a typical representative of the "Jump Dominated" technique; • good connection of individual phases was a result of optimal kinaesthetic control and dynamic balance; • the model of duration of support and flight phases in the hop, step and jump indicates a tendency towards high stability; • horizontal velocity varied in the individual take-off actions with the largest difference noticed in the step phase; • a particular reduction of horizontal velocity in the take-off action of the jump phase was a result of an emphasised increase in vertical velocity, which ensured optimal height of the flight trajectory in this phase. Although the present study has been carried out on a single athlete, the importance of the study for practice, sports science and sports biomechanics is significant. The results are particularly valuable as they were acquired with the use of the latest measuring technologies. Only a high standard of measuring procedures can ensure precise results, which can help coaches and athletes in the process of planning and control of training.
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