IT TOOK ten days, but Brazil’s second gold medal of the Olympics—won by pole vaulter Thiago Braz da Silva—was warmly welcomed by the games’ host nation. Mr da Silva broke the Olympic record in Rio de Janeiro on August 15th, and went on to win the competition. He beat the previous Olympic best of 5.97m, set by French vaulter Renaud Lavillenie in London four years ago, by six centimetres. Mr Lavillenie was in Rio to defend his title, but could only finish second. He was jeered by the partisan crowd throughout the competition and even on the podium, in a display of nastiness that Thomas Bach, the president of the International Olympic Committee, has described as “shocking” and “unacceptable at the Olympics”.
The needless booing from the stands marred what should have been a moment of triumph for Brazilian athletics. Yet impressive as it was, Mr da Silva’s bound over the bar could only match the world record for the pole vault as it stood nearly 30 years ago, in 1987: since then the record has crept up to a heady 6.16m, set in 2014.
In fact, of the various jumping competitions for men, the pole vault is the only one to have seen regular progression in the world record throughout its history. Since the International Association of Athletics Federations (IAAF) began keeping track of these things in 1912, the men’s triple-jump and long-jump world records have increased around 18%; the men’s high-jump world record has improved by 23%. But today’s pole-vault world record is 53% higher than the 1912 record, set by American Marc Wright on June 8th 1912.
For women, the improvement in jumping is more pronounced all round. High, long and triple-jump records have risen around 45-50% in the last century; the pole-vault mark has lifted from a paltry 1.44m to 5.06m, set in 2009 by Yelena Isinbayeva, a towering Russian responsible for setting 17 of the last 19 records. (Ms Isinbayeva has been barred from this year’s games along with most of the Russian track-and-field team, after the World Anti-Doping Agency (WADA) found evidence of state-sponsored steroid use.)
Though no data is available to compare events, it seems unlikely that the enormous gains in the pole vault are due to a proportionately higher number of people giving it a go: the sport seems no less popular than other jumping disciplines. So what has resulted in vaulting coming on leaps and bounds, while similar-styled sports hop and skip along?
One cause is the equipment. The pole gives athletes a way to store and convert horizontal kinetic energy into a vertical leap, explains Peter McGinnis, a professor in kinesiology at the State University of New York at Cortland. They haven’t grown in length—the limit remains 5.3m—but there was a marked improvement in pole-vaulting records with the move from static wooden or steel poles to more flexible carbon-fibre ones in the 1960s: the men’s world record stretched 64cm further from the ground in that decade.
Manufacturers turned next to improving durability. Steve Chappell of UCS, a manufacturer of sporting equipment, explains that the biggest modern development has been the dependability of poles, which gives athletes the confidence to push themselves further. Because poles are now less likely to break when they bend, vaulters are more willing to trust them.
This is shown most clearly by where vaulters grip the pole before hurtling themselves towards the bar, explains Pat Manson, a former professional vaulter who now trains athletes in the discipline. When Mr Manson was competing in the 1980s and 1990s, vaulters would grip the pole half a metre from the top. Now, they are giving themselves less than 15cm leeway. Both Mr Manson and Mr Chappell single out Mr Lavillenie, the men’s world-record holder, for being particularly daring in his grip. Holding the pole closer to the end allows more bend and spring when released, thrusting the athlete higher.
There are other explanations, too. For one thing, the pole vaulter of 2016 bears little resemblance to the vaulter of 1912. Athletes have become bigger and bulkier, packing muscle more densely onto their bodies, which gives them the explosive force required to fling oneself several metres into the air. And as sports science improves, athletes are eking out the last few centimetres of height by honing their techniques. Mr Lavillenie is not the biggest athlete, but he is the most fluid. He may also be the most foolhardy, flinging himself with wild abandon with nary a grip on the tip of the pole. Believing that the rod you are using to leap six metres in the air is unlikely to snap makes a world of difference.