24 August, 2014

Pole vault: a women’s sport

Back in the days when women were not pole-vaulting (officially) I was dreaming of the day this missing discipline would be introduced, making it possible for women to compete in the decathlon. Alas, things did not go this way. Women have been participating in pole vault competitions for 20 years now but, as I am deploring in a previous article of mine, the feminine decathlon is a stillborn discipline.

When I started planning for a pole vault article I thought that, for women, there has never been a “before” and an “after”: the era of feminine pole vaulting started with fiberglass poles. This made me curious and I started researching: was it true that women never tried vaulting with, say, bamboo poles? It turned out that nothing was further from the truth. Indeed there were some serious indications that women did indeed vault. Even if this photo 

from the late 1800s were fake there is this magazine cover from the 20s

showing a young lady vaulting with a bamboo pole in perfect style.

Thanks to the contributors to the site PoleVaultPower.com I was able to find the women's world record progression. It is unofficial, of course, but who cares about such details. So the oldest recorded performance of a female pole vaulter was 1.72 m by R. Spencer in 1911. No details are known about the implement which could have been wood or bamboo. By 1935 the record was 2.53 m by Z. Romanova, most probably with a bamboo pole. In 1952 D. Bragg (the sister of Don Bragg who would later become an olympic champion) broke this record (one can surmise, with a metal pole) with 2.59 m. The first to jump over 3 m was J. Edwards who, from 1981 to 1983, took the record from 2.61 m to 3.59 m. By that time the fiberglass poles had dominated the pole vault scene. 

The first official world record was homologated in 1992. At that time several chinese athletes had improved the record from 3.72 m to 4.02 and the first official record, due to C. Zhang was 4.05 m. The supremacy of the chinese vaulters was soon to end and the world record became a european-american affair, with an australian interlude due to E. George. The first female vaulter over 5 m is the great Y. Isinbayeva who improved the record 17 times.

When I started following women’s pole vault I was not very happy with their style. I was not convinced by D. Bártová’s technique and I did not have the occasion to watch E. George (who has an excellent style) in action. Remember, YouTube was still years away. The first great, to my eyes, female pole vaulter, the one who jumped just like her male colleagues, was A. Balakhonova, European champion and record holder with 4.55 m.

Anzhela Balakhonova

But that was back just before the turn of the century. The new generation of female pole vaulters was arriving with S. Dragila, S. Feofanova and Y. Isinbayeva who, with their strength and grace, 

Liz Parnov in a most probably failed attempt (but I like the acrobatic style)

changed the face of this spectacular discipline making it a women’s sport.

11 August, 2014

Pole vault: before & after

The before and after in the title refer obviously to the fiberglass revolution that changed completely the nature of pole vaulting. Pole vaulting with wood, bamboo or metal poles is a different sport than the one with fiberglass poles. One can wonder how IAAF with their ultra-conservative attitude did allow for this revolution. It is my feeling that they did not see it coming. Fiberglass poles had been around for more than a decade before becoming world-record stuff. But let us see how all this came to be.

Pole vaulting has been a human activity for centuries before becoming a competition sport. One reads accounts about (pole) bull jumping in Minoan Creta, (horizontal) canal jumping in the Netherlands, but it was in Germany where pole vaulting became part of the gymnastics curriculum at the end of 18th century with best performances around 2.5 metres. By the middle of the 19th century the record stood at around 3.20 m. However at that time the athletes were not really “vaulters” but rather “climbers”. The pole was shod at the lower end with an iron tripod: the athlete planted it in front of the bar started climbing and, when the pole started falling forward, he drew up his knees passing the bar in a sitting  position.

I admit that I had trouble understanding the “climb” technique until I saw a video of canal jumping competition where this technique is used, albeit for horizontal jumps, till today. The best performance with the climbing technique, before being banned, was over 3.5 m. 

The first poles were wooden ones, made from ash, hickory, spruce or cedar. they were shod with a single spike at the lower end to prevent slipping. They were much longer than the height of the bar and quite heavy, which required a grip with the two hands well apart. (It is probably the length of these wooden poles which would inspire a ridiculous rule if there is one. Obviously if the pole reaches higher than the bar it may drop it if it is incorrectly released. But why on earth if the pole does not reach all the way up should the jump be invalidated if the pole passes under the bar? Fortunately this stupid rule has now disappeared).

At the very end of the 19th century, and the beginning of the 20th, three major changes projected pole vault to the modern era. 
The first was the introduction of the plant hole. Replacing the spike it allowed a firmer positioning of the pole in front of the bar. As expected, this did not go smoothly at the beginning. In the 1908, London, Olympics the american vaulters had to fight tooth and nail in order to be allowed to dig a plant hole (moreover it had to be positioned off-centre so as not to create problems to people jumping with a spiked pole). The plant hole was replaced in 1924 by the plant box with standard dimensions.
The second improvement was a technical one. It was introduced by. R. Clapp who established a world record of 3.62 m with it. He was the first athlete to use the lower hand slide, bring it close to the upper hand and pulling with both hands, an undeniable advantage. This technical innovation became the standard style surviving until the advent of fiberglass poles. 
The third progress was in the choice of pole material. While westerners were jumping with wooden poles, japanese athletes have been using bamboo poles for decades. The first athlete to break a world record with a bamboo pole was the french F. Gonder with 3.69. He went on to win the 1906, Athens, intercalated Olympic games and has even jumped 4 m unofficially, despite his unorthodox (to say the least) technique.

From the beginning of the 20th century onwards bamboo poles dominated the pole vault scene. They had definite advantages over wooden poles since the latter could not bend and could not transfer horizontal motion into upward motion efficiently. Bamboo poles had some bend and, moreover, being lighter, they allowed for a faster approach.

The IAAF started homologating world pole vault records in 1912 with a 4.02 m record by M. Wright culminating at the fabulous 4.77 m record of C. Warmerdam (probably the greatest pole vaulter before S. Bubka), which would survive for 15 years.

In 1948 another type of pole made its appearance: the swedish steel pole. Its advantages over bamboo were obvious: it did not break, was lighter and had practically the same spring as bamboo. An american brass and aluminium alloy pole was introduced practically at the same time. The metal poles met with great success but the records of Warmerdam were so extraordinary that only a modest progress was registered with these new poles (in fact a mere 3 cm as far as the world record is concerned).

While steel poles were becoming all the rage the real revolution started but went practically unnoticed. A California firm started producing fiberglass pole vaults. While they met with considerable success at the beginning the athletes soon became disillusioned since these first poles were rapidly fatiguing and breaking. However, once people had the idea of a fiberglass pole the progress in quality was rapid. The name of H. Jenks is that one usually encounters as that of the “father” fiberglass poles. In any case, he is the first person in North America to patent a fiberglass vaulting pole. People refer to his friendship with B. Mathias as the reason for the latter to use a fiberglass pole in the Olympic decathlon. 

While I doubt this fact, as far as the 1948 Olympics are concerned (too early!) it is almost sure that he used a fiberglass pole in 1952. The only  other two olympians to use such a pole up to 1960 were my compatriot G. Roubanis, bronze medal in the 1956, Melbourne, Olympics and European record holder,

and the puertorican R. Cruz, 5th in the 1960, Rome, Olympics. (In fact Roubanis himself says that he does not remember whether he used a metal or fiberglass pole in Melbourne. He had been experimenting with fiberglass poles and he had them with him in Melbourne though).

The point it that all these athletes were using their fiberglass pole as if it were a standard, metal, one. Then, in 1961, everything changed. The poles had evolved, tailored to the athlete’s weight and, what is even more important, they could bend without breaking. (H. Jenks was instrumental in this). The first athlete credited with employing a wide handhold and bending his pole was A. Dooley. Immediately he found imitators and the first fiberglass world record was soon established by his teammate G. Davies with 4.83 m. (In fact the second one was also established by a team-mate of Dooley’s, since the latter went to train with Uelses who, in 1962, broke Davies’ record with 4.89 m). The revolution had started and it was too late for IAAF to forbid the use of the new poles. 

Cornelius Warmerdam tried a fiberglass pole and, jumping 4 m with it, predicted that people should be able to jump 5 m. It turned out that this was a very timid prediction. 

The present article wouldn’t have been possible without the precious help of Becca Gillespy. While researching for this article I stumbled upon a reference to the book “Illustrated History of the Pole Vault”, a book almost impossible to find. 

I searched for it and I found a reference to it in the store of the Pole Vault Power site. I sent an email immediately to Becca who managed to find a copy (the last one apparently) of the book for me. A million thanks Becca.

04 August, 2014

An interesting blog on the science of sport

I am always complaining on the absence of interesting blogs on athletics. Still, from time to time, mostly by chance, I find a blog that is really to my taste. This time it’s the blog 

Science in Sport

by two young PhDs from South Africa: Ross Tucker and Jonathan Dugas. 

Their blog is very interesting but I am afraid that it is in a semi-abandoned state. However, one of the bloggers is very active on Twitter, so there is still hope for the blog.

I should also point out that the two bloggers have published a book, in collaboration with  Matt Fitzgerald: The Runner's Body: How the Latest Exercise Science Can Help You Run Stronger, Longer, and Faster.

You can find it on Amazon at a very reasonable price.

01 August, 2014

On blade runners

I would have preferred a title like “Should blade runners be allowed to participate in competitions for two-legged athletes?” and let Betteridge’s law answer it (which states that “any headline which ends in a question mark can be answered by the word no”) but it is unfortunately too long. 

What motivated the present post is the recent outstanding performance of Markus Rehm who won the german championships with 8.24 m. 

Rehm has lost his right leg below the knee in an accident and he uses a prosthetic leg like the ones Oscar Pistorius is using. I was planning for some time now to write my ideas on Pistorius and the other “blade runners” and Rehm’s record gave me the motivation. 

Now, don’t get me wrong. I have great respect for athletes who train and compete despite their physical handicap. To attain the highest level requires not only great efforts but also lots of courage and confidence. However the question is that if we do not know for sure whether an athlete gets an advantage from the prosthetics that he wears, allowing him to compete with able-bodied athletes may turn out to be unfair to the latter.

Pistorius has double below-knee amputations, and competes in the T44 category (for single amputees, although, being a double amputee, he is entitled to participate in the T43 class). He has several gold medals from the 2004, 2008 and 2012 Paralympics, and world records with 21.30 at 200 m and 45.07 at 400 m. He runs with J-shaped carbon-fibre prosthetics. Pistorius’ prostheses weigh less than half as much as the limbs of an able-bodied male runner. 

Before reaching a conclusion on whether blade runners (and by this term I refer to all athletes in the T44 and T43 categories) should be allowed to compete with able-bodied athletes I would like to present some arguments. 

First, what do the rules say?

On 26 March 2007, the IAAF amended its competition rules to include a ban on the use of "any technical device that incorporates springs, wheels or any other element that provides a user with an advantage over another athlete not using such a device". (Pistorius challenged this decision at the Court of Arbitration for Sport and managed to obtain the permission to compete).

What do scientific studies say?

The first study was conducted by G.P. Brügemann (Univ. Köln) who concluded that the majority of work is done in the blade (without muscular work), that the blade returns 90 % of the energy compared to 60 % for the ankle joint and that this kind of locomotion entails lower metabolic costs. 

Looking at this data I wonder why hadn’t Pistorius ever tried to run a 800 m. Given the shape of the energetic cost of his effort he should have been even better over 800 m.
The presentation of Brügemann ends with two citations. First by H. Herr (MIT) who states that “People have always thought the human body is ideal. It is not”. Second by B. Nigg (Univ. Calgary) “I would like to challenge the biomechanics community to develop prostheses that will produce world records in many track and field disciplines. It should not be too difficult”. I feel that we are almost there.

The methodology of Brügemann was challenged in a study by Weyland and collaborators at Rice University. While they noted that Pistorius can reposition his legs considerably faster than other able-bodied sprinters because the blades are so lightweight, giving him an overall speed advantage, they concluded that, “running on modern, lower-limb sprinting prostheses appears to be physiologically similar but mechanically different from running with intact limbs.” That is to say that metabolic costs and endurance are similar to runners with intact limbs. Running at lower speeds does not seem to give Pistorius as much of an advantage (such as the speeds that would be used in longer races instead of sprints). Still I would have liked to see what an athlete like Pistorius could do over 800 m.

The discussion is going on concerning the existence or not of an overall advantage for blade runners. Arguments pointing out that, running with blades, the athletes must pop straight out of the blocks and face a greater air resistance or that they must work harder against centrifugal forces, are perfectly acceptable however unless precise, rigorous studies are carried through they remain qualitative.

What do able-bodied athletes say?

Following the stunning performance of Rehm, fellow competitor Sebastian Bayer said that Rehm's prosthetic limb could provide a catapult-like effect to his jump."The prosthetic seems 15 centimetres longer than the other leg" said Bayer. Rehm countered by stating that the prosthetic is three, four centimetres longer than his other leg, but the disparity keeps him from hobbling during the run-up to his jump. So, the length of the prosthetic limb appears to be an issue, which brings us to the next paragraph.

What do blade-runners themselves say?

Following the surprising victory of Brazil's A. Oliveira at the 200 m of the London, 2012, Paralympics, Pistorius, who was second in that race reacted by saying: “We aren't racing a fair race. I've never seen a guy come back from eight metres behind on the 100 m mark to overtake me on the finish line”. Pistorius was convinced that the running blades used by Oliveira and the bronze medalist Blake Leeper were too long, and called for the International Paralympic Committee to investigate. As expected, the next day Pistorius apologised for the timing of his comments saying that he would never want to detract from another athletes' moment of triumph.
It goes without saying that the IPC has rules regarding the length of the blades which is determined by a formula based on the height and dynamics of the athlete.

Just for completeness sake I must point out that the problem of Pistorius is that he cannot alter the length of his blades if he wants to continue to compete in able-bodied competitions. To do a crossover like that, he can only run on blades that have been cleared for use by the IAAF. Longer blades, of the kind Oliveira used, are only legal in Paralympic events. If Pistorius switched, he would not be able to run in non-disabled competitions. Besides which, he would undermine his own argument that his success is about the body above the knee, rather than the technology below it. Of course, all this will most probably become moot given the recent legal troubles of Pistorius.

So, what is the conclusion?

I think that blade runners (and jumpers) should contend themselves with their own circuit of competitions. They have Paralympic Games organised in parallel with the Olympic Games. They are getting more and more recognition and praise by the public and the media. I am looking forward to blade-runner records surpassing those of able-bodied athletes and I would definitely welcome them. After all wheelchair records have been leaving running records in the dust. But trying to have prosthetics-carrying athletes competing along able-bodied ones will only lead to suspicion and perhaps to the temptation of cheating. So, the answer to the question raised in the first paragraph is a resounding “no”.