The mean official results (2.27 ± 0.04 m) in this competition were one of the poorest during the history of the track and field World Championships since 1983. On the other hand the mean height of the COM during the highest point of the flight was 2.32 ± 0.04 m and that corresponds well to the earlier studies when only six to eight best jumpers were analyzed. From the technical point of view the competition was interesting, because all different kinds of variations of the Fosbury-flop techniques used in this final. These variations are power versus speed -flop and different kinds of hand techniques which are; original running arm action (Topic), leading running arm action (Holm), fast double arm action (Krymarenko) and wide double arm action (Baba). The results of the approach run demonstrate the fastest run-ups ever recorded. When comparing these values to the earlier studies (Iiboshi et al. 1991; Brüggemann and Arampatzis 1997; Dapena 2000), it seems clear that nowadays horizontal approach velocity is increasing. The present results show clearly that the vertical velocity and the height of COM at the end of take-off phase together determine the height of the flight (r=0.75, p<0.01; r=0.1., n.s, respectively). Thus, the vertical velocity of the athlete at the end of the take-off phase determines how high the COM will rise after TO. The most important factor related to the vertical velocity of TO is the low COM position at TD (r=-0.70, p<0.01). These findings are well in agreement with the theoretical findings of Alexander (1990) and the earlier experimental results (Dapena, 1980; Greig and Yeadon, 2000). The partial heights are very close to the data reported by Iiboshi et. al. (1991) as well as Brüggemann and Arampatzis (1997 ). These results showed that COM height during the TD is related to hand technique more than physique. Topic, who is using original running arm action, had a lowest value of 68 % of the body height compared to the highest values (73%) of the jumpers who used wide double arm action. This difference in arm actions refers 8 cm, if the jumper is 2m tall. On the other hand, speed floppers like Topic have a shorter take-off time, greater knee angle and higher horizontal velocity during the take-off phase than power floppers. Thus, high knee joint stiffness is crucial for the speed floppers who probably store more elastic energy to the muscle-tendon complex than the power floppers whose take-off is based more on the concentric muscle action. The increased muscle activity of the leg extensors in the braking phase of the contact is also a prerequisite for efficient storage of elastic energy (Komi and Gollhofer, 1997). It can be concluded that high jumpers with different body types, physical characteristics and performance techniques have good possibilities to compete successfully in the highest level. The different variations of the flop techniques enable the utilization of the best physical capacity of the each individual jumper. Therefore it seems that there is not only one ideal technique to achieve good results.
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