Markku Köykkä:

LoikkaajanLiikkuvuus.pdf

*****************************************************

 Biomechanical Analysis of the Triple Jump

Heikki Kyröläinen, Paavo V. Komi, Mikko Virmavirta and Juha Isolehto

Neuromuscular Research Center

Department of Biology of Physical Activity

University of Jyväskylä

Jyväskylä, FINLAND

Introduction

Triple jump has been considered to be a young discipline but, however, it has been performed already in Antic Greece as well as in Ireland in 632 b.Cr. The first man who jumped over 14 m was a Scotsman Leiden, who jumped by using only one leg (hop-hop-jump). This technique was used also an Irishman Shanahan in his triple jump performance of 15.26 m. In the first modern Olympic Games in 1896 the winner of the triple jump, an American Connolly, utilized the same technique as well but his final result was only 13.71.

The present technique (hop-step-jump) started to dominate in the beginning of the 20^th century. The first IAAF world record was registered in 1911 with a jump of 15.52 by Daniel Ahearn (USA). Naoto Tajima (Japan) was the first athlete who jumped over 16 m in the Olympic Games in 1936, while 17 m was jumped first time in Olsztyni 5.8.1960 by Josef Schmidt (Poland). (17 m was jumped first time in Mexico City in 1968 by Josef Schmidt (Poland)) . In that year started Victor Sanejev’s winning period in the Olympic Games (Mexico City 17.39, Munich 17.35 and Montreal 17.29). In addition, he achieved silver medal in the next Olympic Games in 1980 by a performance of 17.24. Later Joao Carlos de Oliveira and Willie Banks approached the 18 m mark with 17.89 in 1975 and 19.97 in 1985, respectively. Jonathan Edwards improved dramatically the world record in the World Championships in 1995 with a performance of 18.29 m.

Among the female jumpers, triple jump is officially only 16 years old. Namely the IAAF holds a world record list for women since the beginning of 1990. In the first World Championships where triple jump for women was organized in 1993, the winner (Anna Birykowa, Russia) jumped 15.09 m. In the next championship in 1995 Irina Kravets improved the record to 15.50. However, the mean distance of the best eight finalists have not changed during the last 12 years either in women or men (Table 1).

The present study follows the series of studies collected from the Olympic Games, World Championships and European Championships. The purpose was to examine performances of elite triple jumpers under competitive conditions in order to determine why the medallists were better than their poorer counterparts.

Methods

Data Collection

The subjects of this study were eight best finalists in the women’s and men’s triple jump at the the 10^th World Championships in Helsinki 2005. All jumps were filmed using two audio synchronized high-speed video cameras (HSC-200) with Pan and Tilt heads (Peak Performance Tech. Inc.) operating at 200fps and the best trials of each jumper were selected for further analysis.

Two high-speed (200 fps, shutter speed 1/5000) were located 10 meters higher than the track level on the special platforms. Both cameras followed jumpers throughout the trial while the angle between the optical axes of these cameras varied between 60 to 120 degrees. Camera to camera distance was 96 meters.

Image space was calibrated before and after the finals, by using the proper technique for pan & tilt recording with three standard calibration rods (height: 2.438 m) placed exactly vertical position, along the side of the run-up lane (x –axis; parallel with run-up lane). Horizontal distance from rod to rod was 30 meters. Rod 2 was aligned to the edge of the take-off board. Origin was later translated to mid-point of the take-off board.

Data Analysis

Afterwards, the digital video signal was captured via video board to the Motus (Peak Performance Tech. Inc.) motion analysis system. On the video recordings of the jumps, 15 body landmarks (wrist, elbow, shoulder, hip, knee, ankle, tip of the toe on both sides of the body and the head) were digitized manually for the four last strides of the approach and the hop, step and jump until to landing. The 3D model of the jumper’s body consisted of 12 segments. Segment parameters used for determination of the body COM were taken from the data of de Leva, 1996 (adjusted from Zatsiorsky-Seluyanov’s segment inertia parameters 1990). The kinematic data was smoothed using a Butterworth fourth-order-zero-lag filter and a cut-off frequency of 20 Hz based on residual analysis and qualitative evaluation of the data.

Results

The mean official distance of the best 8 jumpers in the men’s final was 17.31 ± 0.17 m and of the 8 best in the women’s competition 14.66 ± 0.26 m. Tables 2 and 3 summarizes the results of commonly used distances in the triple jump. The both genders hit the board with quite similar precise (0.10 ± 0.06 m for women and 0.08 ± 0.05 for men) but the total lost of distance (sum of the toe-to-board distance and poor landing) was longer among men (0.18 ± 0.05 m vs. 0.29 ± 0.06). This suggests that men had poorer landing technique than women.

Approach

The mean approach velocity was 9.3 ± 0.2 m×s^-1 for women and 10.2 ± 0.2 m×s^-1 for men (Tables 4 and 5). No statistically significant relationships were noticed between the approach speed and the final result either in women or in men (Figure 1). However, in more heterogeneous population this relationship would be significant, because in the horizontal jumps the run-up speed is the most essential factor for a successful performance. In the present study, the second last approach stride was longer in men than in women but interestingly the length of the last stride was the same (Tables 4 and 5). This may be caused by a stronger braking phase in women when approaching the take-off. On the other hand, the mean stride lengths were exactly the same as in WC 1997 in Athens (Brüggemann & Arampatzis, 1997).

Hop, step and jump distances

The absolute and relative distances of the hop, step and jump have been presented in the tables 6 and 7. The relative distance of the hop was on the average the same for women and men (36.2 %), while the step was longer in women than in men (29.4 % vs. 28.8 %). Interestingly, the women have improved their technique since the WC 1997 when the partial ratio of the step was only 27.7 % (Brüggemann & Arampatzis, 1997). However, it is still notable that different performance strategies exist in the triple jump as Hay (1992) has defined, although the number of jumpers using a balanced technique has increased. The more detailed analysis among men revealed that contact times gradually increased from the last run-up stride to the jump (Table 8). The jumper utilizing hop dominated the technique (hop percentage is at least 2 % greater than the jump percentage), had longer contact times (total of 2.260 s) as well as flight times (total of 1.780 s). This suggests that the hop dominated jumpers had longer force production times and they can be classified as strong jumpers.

Velocities during the hop, step and jump

During the take-off for the hop the horizontal CM velocity decreases and vertical velocity increases. The horizontal velocities at the take-off for the hop were 8.3 ± 0.2 m×s^-1 for the women and 9.7 ± 0.2 m×s^-1 for the men. In the phase of the performance, the decreases were greater in men than in women (0.9 ± 0.1 m×s^-1 vs. 0.7 ± 0.1 m×s^-1), while the women reduced their horizontal CM velocities dramatically during the step and jump phases as compared to the men (Tables 11 and 12). The vertical velocity was the highest in the jump and the smallest in the step among both genders. The mean take-off angles differed, especially, in the hop phase between the women and men (15.5 ± 1.4 deg for women vs. 13.8 ± 0.9 deg for men) but, however, the take-off angle was the greatest and almost the same in the jump phase in both genders.

Summary and Conclusion

The best trials of the eight male and female triple jump finalists were studied using high speed video based motion analysis. This study follows the series of studies from the several Championships and Olympic Games. Thus, the utilized parameters have been well validated and repeated during the approach run, hop, step and jump.

The results of approach run indicate that the run-up speed for the men was slower than in WC 1997 but faster than in WC in 1987. For the women the run-up velocity did not differ from the earlier international competitions. All the subjects decreased their horizontal velocity of CM during the take-off for the hop, and subsequently to the step and to the jump. In conclusion, high approaching speed combined with its maintenance during the hop, step and jump by short contact times enable good prerequisites for a successful performance. This requires high preactivity for timing of muscular action with respect to the ground contact and for creating high muscular EMG activity during the braking phase. 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). As a consequence of the high prelanding and braking activity of the leg extensor muscles, unnecessary yielding of the jumper during the braking phase might be prevented and the horizontal speed is better maintained.

References

Brüggemann G.-P. and Arampatzis D. (1997) Triple Jump. In: Biomechanical Research Project at the VIth World Championships in Athletics, Athens 1997: Preliminary Report, H. Müller, and H. Hommel (eds.). New Studies in Athletics, 13, 59-66.

Hay J.G. (1990) The biomechanics of the triple jump: a review. J. Sports Sci. 10(4): 343-378. Review.

Komi P.V. and Gollhofer A. (1997) Stretch reflexes can have an important role in force enhancement during SSC exercise. J. Appl. Biomechanics 13: 451 – 460.

Table 1. Results (m) of the men’s and women’s triple jump finalists at the WCs in 1993, 1995, 1997 and 2005.

Table 2. Official, effective, total lost and toe-to-board distances – women’s final WC 2005.

Table 3. Official, effective, total lost and toe-to-board distances – men’s final WC 2005.

Table 4. Stride lengths and CM’s horizontal velocity during the last two strides in women.

Table 5. Stride lengths and CM’s horizontal velocity during the last two strides in men.

Table 6. The absolute (m) and relative (%) phase distances – women’s final in WC 2005.

Table 7. The absolute (m) and relative (%) phase distances – men’s final in WC 2005.

Table 8.        Mean contact and flight times (s) during the last run-up stride and during the hop, step and jump in men.

Table 9. Horizontal (v_x) and vertical (v_y) CM velocities as well as take-off angles for the hop, step and jump – women’s final in WC 2005.

Table 10. Horizontal (v_x) and vertical (v_y) CM velocities as well as take-off angles for the hop, step and jump – men’s final in WC 2005.

Table 11. Changes of the horizontal CM velocities (m×s^-1) in women.

Table 12. Changes of the horizontal CM velocities (m×s^-1) in men.

 *******************

Paluu Valmennus-sivulle