毛片久久网站小视频,国产亚洲第一精品,女同另类激情在线三区,正在播放国产对白孕妇作爱,日韩成人无码影院

Pedal power

By Lei Lei and Matt Hodges (China Daily)
Updated: 2007-06-08 09:51

Sketch of the Laoshan BMX venue.

Imagine a pack of racers tearing down a BMX course with a UFO-shaped velodrome and Beijing in the background, as remote-control cameras catch all the action from wires overhead.

Crowds will gather at both ends of the snaking course, near the 8-m-high rolling start ramp and at the lower-elevation finish line, as helicopters capture aerial beauty shots.

"No one has ever seen a track like this before," said Mats Notlind, a technical director with the International Cycling Union (UCI), who was helping with the venue construction in Beijing last week.

"I would say it is the most perfect track ever built," said his colleague Johan Lindstrom, the UCI's BMX sports coordinator.

Forget Travis Pastrana. When BMX makes its Olympic debut in Beijing next year it will be in a space age setting that breaks the mould in terms of what the sport has seen before.

BMX Begins: How motocross 'evolved'

It started in the late 1960s in California, has since spawned a cult following at the Summer X Games and is now one of the most exciting sports at the 2008 Olympics.
Bicycle motocross - or BMX to its hordes of disciples - straddles the line between cycling and extreme sports, and has always had an edgy, subcultural feel.
It also generates captivating headlines and the allure of never-before-seen tricks.
Take Travis Pastrana, for instance. He won the Moto X Best Trick at the X Games last August with one of the scariest stunts ever pulled in professional sports: the first-ever double backflip on a BMX.
But the sport has always been about pushing the envelope.
Forty years ago in the US, it first appeared on the radar at a time when motocross (motorbike racing) was enjoying huge popularity stateside.
Children and teenagers with the desire but not the means to participate in motocross sated their appetite by racing bicycles on self-built tracks.
These young daredevils completed the imitation by dressing up in motocross gear. The sport was given the name BMX and the conception was complete.
BMX races are held on circuits of around 350m, featuring jumps, banked corners and other obstacles. Eight riders compete in each heat (qualifying rounds, quarter finals, semi-finals, finals) with the top four qualifying for the next round.
BMX racing was an instant hit, and nowhere more so than in California. During the early 1970s a sanctioning body was founded for the sport there. This is considered the official start of BMX racing, which was introduced in other continents later that decade, notably Europe in 1978.
The International BMX Federation was founded in April 1981, with the first world championships arriving in the following year. BMX rapidly developed as a unique sporting entity, and after several years clearly had more in common with cycling than motorcycling codes. As such, it was fully integrated into cycling's governing body, the Union Cycliste Internationale (UCI), in January 1993.
The US, Europe and Australia have dominated BMX in past years, but it is now growing in international appeal. Beach-loving South America has made rapid strides and the UCI now recognizes official BMX activities by 75 national federations.
Over 1,600 competitors from 32 countries participated in the 2003 World Championships in Perth, Australia.
On June 29, 2003, the International Olympic Committee decided to introduce BMX to the 2008 Beijing Games.
Source: Union Cycliste Internationale

Make no mistake, the Laoshan BMX course in western Beijing's Shijingshan District is going to be the most difficult the world's elite have ever faced.

"There are going to be some falls," said John Pauline of PTW, the Australian architects who are advising on the course. "There are going to be some spectacular falls."

Unlike other venues used for international events that have to cater to all levels of competition, this one has been tailor-made to test the limits of human endurance.

The initial start ramp will give the riders maximum acceleration, bigger air on jumps and a greater risk of personal injury. But for BMX fans, that is all part of the thrill.

"I think the designers are constantly frustrated that they're always building courses that need to be compromised, whereas at the Olympic Games for the first time they can create the most ridiculously hard BMX course to challenge the best riders in the world," said Pauline.

The course will be linked to the neighboring Olympic cycling track (Laoshan velodrome) by a vertical elevator to shrink logistical costs. Together with the nearby mountain biking course, the trio form one of several clusters of Olympic venues that organizers hope will spur development in one of Beijing's less prosperous districts.

In fact, the BMX track comprises two overlapping routes: one for the top 32 men in the world (370m) and another for the top 16 women (a slightly shorter 350m).

To make the men's competition more unpredictable, those who survive the initial rally out of the gates may have a choice of two routes. China's sports officials are mulling opening a junction one third of the way around that lets riders choose whether to stay on the outside or branch inside onto the women's track.

The downside? Those who veer onto the women's side would then have to reconnect with the men's track via an extremely gnarly jump.

Fortunately, the races are single-sex only.

"Some of the major banks that the women are turning around, the men are going to be jumping over, so they're going to have the biggest air, the biggest hang time, if you like, on these bikes, that the BMX world has ever seen," said Pauline.

Lindstrom said the 8m start ramp was a new innovation that was incorporated after it was used successfully in recent World Cups

"You don't really see it on normal BMX tracks, but we knew that we wanted a very exciting format in the Olympic Games," he said, adding that the riders will also have to take on gravity: the finish line is 4m lower than the start, creating a natural momentum for the riders that keeps on snowballing until they cross the finish line.

It took the UCI three years to design the track, a feat belied by its seemingly simple layout and lack of obstacles. Lindstrom said much thought went into taking the sport to the next level through a carefully engineered venue.

"While we were designing the track, we were also developing the sport," he said. "We don't want to just go into the Olympics with the traditional format. We want to create something spectacular."

The format of the course also developed through testing at recent World Cup series. The UCI sought feedback from riders and viewers alike to make 2008 a banner year for BMX.

"Now we finally got the right concept," said Lindstrom. "It's even more amazing in real life than in the 3D drawings we looked at."

As the biggest-ever BMX venue, the track has sucked up vast amounts of materials: 10,000 cubic meters, compared to 3,000-4,000 in regular tracks.

The rough layout of the track was finished earlier this month. It will be fully built before Beijing hosts the UCI BMX Supercross World Cup test event from August 20-21.