Chinese Si Tianfeng crosses the finish line to win the Good Luck Beijing 50km IAAF Race Walking Challenge at the National Stadium, also known as "Bird's Nest", in Beijing, April 19, 2008. [Xinhua]

BEIJING -- Three Chinese athletes swept the medals of the men's 50km competition of the IAAF Race Walking Challenge in Beijing on Saturday.

Si Tianfeng won the race in three hours 45 minutes and 13 seconds, followed by Zhao Chengliang in 3:47:14 and Li Jianbo in 3:52:12.

The three medalists and the fourth fastest Yu Chaohong, who lost to the bronze medalist by six seconds, are all hopeful for Olympic athletics of the Chinese national team.

Si, a 23-year-old from Shandong, said: "I'm very excited to win my first international gold medal."

He said he did not have a specific plan in the race, but to just follow the leading group.He actually led after 25 kilometers.

"I didn't do my best in today's competition which was just a qualification," Si said. "I hope I can do better in the Olympics."

"We've joined half dozen of training camps in plateau near Shangrila in Yunnan Province, 3,600 to 3,700 meters above sea level, which helps greatly improve our performance in low-altitude competition," said the silver medalist Zhao.

High altitude training has been adopted by the Chinese national athletic team since it was built last September to narrow the gap between Chinese and foreign race-walkers.

The world record for the men's 50km walking, a dull and tedious game as described by Chinese players, is held by Australian Nathan Deakes in 2006 in 3 hours, 35 minutes and 47 seconds.

Chinese national team has made an internal line of less than 3:42:00 for Olympic qualification among those racers.

"We have went to Shangrila for six to seven times alternated by low altitude training in areas with high humidity level which has been used to simulate summer weather in Beijing," Li Jianbo said.

All the medalists said the air condition on Saturday around the National Stadium was not a problem which has been criticized by some foreign players who on Friday warned that pollution will have worse effect on long distance race.

"I think the air quality will be improved before the Olympic Games," Zhao said. "There are several months before the start of the Olympics in August, and the construction will be completed and there will be more trees and grass."

Sources said that the Chinese final list for the Olympic men's 50km walking will be decided on the atheletes' performance in the past several months.

"The race walking challenge is the most important one for considering the final list," the silver medalist told Xinhua, adding that it would probably be released on around May 20.

One of the 42 test events before the Olympics in August, the IAAF Race Walking Challenge attracted athletes from a few countries to participate in.