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The Evolution of High Jumping Technique: Biomechanical Analysis PowerPoint Presentation
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The Evolution of High Jumping Technique: Biomechanical Analysis

The Evolution of High Jumping Technique: Biomechanical Analysis

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The Evolution of High Jumping Technique: Biomechanical Analysis

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  1. The Evolution of High Jumping Technique: Biomechanical Analysis Jesús Dapena Department of Kinesiology Indiana University U.S.A. adapted from the Dyson Award Lecture at the XX International Symposium on Biomechanics in Sports Cáceres, Spain, 2002

  2. There was no high jumping event in the ancient Greek Olympic Games. High jumping seems to have its origin with the Celts (Tailteann Games).

  3. It started as a physical education activity for children. from GutsMuth,1797 But modern high jumping began in Germany in the late 1700s.

  4. Then it developed into a competitive sport in England in the early 1800s. And soon after, it spread to Canada and the United States.

  5. basic principles of high jumping: To clear a high jump bar, it is necessary to drive the center of mass (c.m.) of the athlete to the largest height possible. It is also necessary to move the body in the air in a way that will allow the athlete to clear a bar set as close as possible to the peak height reached by the c.m.

  6. peak height reached by center of mass (c.m.) effectiveness of bar clearance bar height cleared

  7. For a given peak height of the c.m., lowering some parts of the body makes other parts of the body go higher. This is the mechanical principle that high jumpers have used to improve the effectiveness of the bar clearance.

  8. Techniques have progressed a lot since the beginning of modern high jumping around 1800. And every new technique was named after an improvement in the bar clearance. Let’s look at this progression in the bar clearance technique.

  9. (no technique) legs-up ~1800 progression of bar clearance effectiveness By lifting the legs, the trunk and head get lower, and the c.m. stays at the same peak height as before. But the athlete can clear a higher bar. If a high jumper remains in a straight vertical position after taking off from the ground, the height of the bar that the feet can clear will be far below the peak height of the c.m.

  10. scissors The next technique in the evolution of high jumping was the “scissors”, in which the legs are lifted over the bar in alternation one after the other. The advantage of the scissors technique is that parts of both legs are below the level of the bar at the peak of the jump. This increases the height of the pelvis, and therefore the bar height that can be cleared.

  11. legs-up scissors ~1874 progression of bar clearance effectiveness

  12. eastern cut-off The scissors was followed by the “eastern cut-off” technique (sometimes called the Lewden scissors in Europe). In this technique the athlete rotates the trunk into a horizontal position at the peak of the jump. This lowers the trunk, and therefore lifts the pelvis higher than in the simple scissors technique. The result is a higher bar clearance. A disadvantage of the Eastern cut-off is that it requires tremendous flexibility.

  13. scissors eastern cut-off ~1892 progression of bar clearance effectiveness

  14. western roll The eastern cut-off was succeeded by the “western roll” technique. In this technique the athlete cleared the bar on his/her side, with the takeoff leg tucked under the rest of the body. This technique probably did not improve much the effectiveness of the bar clearance in relation to the eastern cut-off. However, it also did not require very much flexibility. Thus, the contribution of the western roll was to provide a reasonably effective bar clearance for a larger number of high jumpers.

  15. eastern cut-off western roll ~1912 progression of bar clearance effectiveness

  16. straddle The western roll was followed by the “straddle” technique. In this technique the athlete cleared the bar face-down, with the body stretched along the bar. The straddle allowed parts of the legs to be lower than the bar at the peak of the jump. This allowed the pelvis to rise to a greater height in relation to the position of the c.m., and therefore improved the effectiveness of the bar clearance.

  17. straddle western roll ~1930 progression of bar clearance effectiveness

  18. While the straddle was replacing the western roll, important innovations were occurring in the run-up and in the takeoff:

  19. improvements in run-up and takeoff: fast run-up Some athletes used a fast run-up. This allowed them to put the muscles of the takeoff leg in fast eccentric conditions during the takeoff phase, which in turn allowed the athlete to exert a larger vertical force on the ground. • * • * (In “eccentric conditions” the muscles are forced to stretch while • they are trying to shorten. In such conditions the muscles can make • very large forces.)

  20. improvements in run-up and takeoff: fast run-up low position at end of run-up Other athletes ran with the c.m. in a low position in the last steps of the run-up. This allowed them to have available a long vertical range of motion for the c.m. during the takeoff phase. This increased the height of the jump.

  21. improvements in run-up and takeoff: fast run-up low position at end of run-up close to vertical at end of takeoff Some athletes noticed that a vertical position of the body at the end of the takeoff increased the height of the jump. This was also due to an increased vertical range of motion during the takeoff phase.

  22. improvements in run-up and takeoff: fast run-up low position at end of run-up close to vertical at end of takeoff double-arm action Other jumpers moved their arms into a backward position in the last steps of the run-up, and then threw them strongly forward and upward during the takeoff phase. This allowed the takeoff leg to exert a larger force against the ground.

  23. improvements in run-up and takeoff: fast run-up low position at end of run-up close to vertical at end of takeoff double-arm action straight lead leg action Still others kicked forward and upward with the lead leg during the takeoff phase, with a motion similar to a soccer kick:

  24. This “straight lead leg” action had the same purpose as the double-arm action, but with an enhanced effect due to the larger mass and length of the leg.

  25. Today we know that all these actions are advantageous for the generation of lift in a high jump. However, this was not clear in the 1940’s and early 1950’s. There were disagreements about what was advantageous, what was detrimental, and what was neutral. As a result, only a small number of high jumpers incorporated one or another of these elements into their techniques, and nobody used all of them.

  26. The United States dominated the men’s high jump event during the first half of the 20th century. Following this tradition, in 1956 Charles Dumas raised the world record to 2.15 m, and then proceeded to win the Olympic Games at Melbourne. 1956 Charles Dumas (USA) 2.15 m (7’ 0-1/2”) But things were about to change …

  27. “The ussians are coming! The ussians are coming!”

  28. In 1957, Yuri Stepanov of the Soviet Union broke Dumas’ world record with a jump of 2.16 m. It was found out later that Stepanov had used a “built-up” takeoff shoe with a very thick sole. This increased the vertical range of motion of the c.m. during the takeoff phase, and thus gave an advantage to the jumper. But the rules current at the time did not limit the thickness of the sole, and therefore Stepanov’s jump was legal. The International Amateur Athletic Federation soon changed the rules, and limited the maximum thickness of the shoe sole to 13 mm. However, the rule was not made retroactive, and Stepanov’s record was allowed to stand.

  29. In 1960, things seemed to go back to “normal”. John Thomas reclaimed the world record for the United States, and raised it to 2.23 m. He was the overwhelming favorite for the gold medal at the Olympic Games to be held at Rome later that year ...

  30. Olympic Games Rome, 1960

  31. #1 Robert Chavlakadze (Soviet Union) #2 Valeri Brumel (Soviet Union) #3 John Thomas (USA) Rome, 1960

  32. Surprisingly, Thomas was relegated to third place in the 1960 Olympic Games at Rome by two athletes from the Soviet Union, Robert Chavlakadze and Valeri Brumel … and by 1963 Brumel had raised the world record to 2.28 m. It became clear that there was more to Russian high jumping than Stepanov’s built-up shoe!

  33. In part, the improvements of the Russian high jumpers were due to advances in physical conditioning methods. But to a great extent they were also due to the work of the Soviet Union’s national high jump coach, Vladimir Dyachkov.

  34. Dyachkov had studied films of the world’s best high jumpers for many years. Through his analyses, he was able to figure out the advantages and disadvantages of the various techniques used by high jumpers. He acquired a particularly good understanding of the advantages provided by the run-up and takeoff improvements that had been gradually introduced during the 1940’s and 1950’s. Before Dyachkov, one or another of these advantageous technique elements had shown up sporadically in the techniques of various high jumpers. Dyachkov incorporated practically all of them into the technique of every one of his athletes.

  35. dive straddle A new variant of the straddle appeared around 1960. It was called the “dive straddle”. In this technique, at the peak of the jump the athlete’s trunk was set at an oblique angle with respect to the bar. This allowed the athlete to drop the head and upper trunk below the level of the bar at the peak of the jump. This raised the hips and the rest of the body, and therefore allowed the athlete to clear a higher height than with the older (“parallel”) straddle. Dyachkov adopted this bar clearance technique for his jumpers.

  36. dive straddle straddle ~1960 progression of bar clearance effectiveness

  37. So by the mid-1960s high jumping technique seemed to be well understood. What was needed was: a fast and low run-up, with preparation of the arms in the last one or two steps, followed by a double-arm action and straight lead leg action that ended in a vertical position of the athlete at the end of the takeoff. The athlete cleared the bar using the dive straddle technique. Dyachkov had figured it all out!

  38. Some athletes were not able to combine effectively a straight lead leg action with the impulse of the takeoff leg. These bent-lead-leg jumpers were quite frustrated, incapable of jumping properly. It is important to point out that not all high jumpers adapted well to this technique.

  39. My interest in high jumping started at about this time.

  40. J.D. Sr. J.D. Jr. My father had been a high jumper when he was young. He used the technique of his day, the eastern cut-off. He took me to many track meets as a child. I liked the sport, and eventually I also became a high jumper (low jumper??). I used the technique of my day, the dive straddle.

  41. Today this technique is called the “Fosbury-flop”. These athletes made the bar clearance on their backs, with the body horizontal and perpendicular to the bar. A completely new technique appeared in the mid-1960’s. It was invented independently by several different jumpers who took advantage of the increased safety provided by foam-rubber landing mats. In 1968, Dick Fosbury won the American University (NCAA) Indoor and Outdoor Championships using this technique. Later that year, Fosbury competed at the Mexico City Olympic Games. And the winner was …

  42. #1 Dick Fosbury (USA) Olympic Games Mexico City, 1968

  43. Until Fosbury’s win at the 1968 Olympic Games, there had been little information on this jumping style. But the Games were televised live, world-wide. The high jumpers and coaches in the audience were able to see the new technique in great detail. It became clear that the bar clearance was not the only difference between the “standard” dive straddle and the Fosbury-flop: Fosbury’s run-up was curved, and his arm and lead leg actions during the takeoff phase were weaker than in the straddle.