Sun Yang's victory in the men's 1500 metres freestyle at the world swimming championships on Sunday may indicate a re-awakening of the country's swimming programme.

The gangly 19-year-old won his second gold medal of the championships in Shanghai, having already won the 800 freestyle title, and touched in 14 minutes 34.14 seconds to break Grant Hackett's long-standing world record.

Canada's Ryan Cochrane took the silver in 14:44.46 while Hungary's Gergo Kis won bronze in 14:45.66.

The long-stroking Sun, who clocked 14:35.43 at the Asian Games last year, was chased hard by Cochrane, though the languid-looking Chinese never seemed bothered as he simply kept up his tempo and then accelerated over the final 100 metres to snatch gold and the record.

The victory ensured China finished second behind the United States on the swimming medal table, with five golds, two silvers and seven bronze medals.

"I think the Chinese team's performance is pretty good," China's head coach Yao Zhengjie said. "Some swimmers had not done as good as we had expected, but overall, we have achieved our goal, mission accomplished."

More importantly, Sun's performances at Shanghai, where he also took silver in the 400 freestyle and helped the 4x200 freestyle team to a bronze, indicated there may be a re-awakening of the Chinese swimming programme, which was mired in doping controversies in the 1990s.

DOPING CONTROVERSY

The Chinese won 12 gold medals at the Rome world championships in 1994 but the programme was stigmatised by suspicions of systematic doping in the 1990s that reached its nadir at the world championships in Perth in 1998.

Four swimmers failed out of competition doping tests conducted before the championships while another, Yuan Yuan, was caught at Sydney airport with human growth hormone in her bags.

Chinese authorities vowed to clean up the sport, which coincided with a drop-off in international performances and it took until the Beijing Olympics in 2008 before the country began to re-emerge on the world stage.

Liu Zige led home compatriot Jiao Liuyang to win the women's 200 metres butterfly, Pang Jiyang took bronze in the women's 200 freestyle while the women's relay teams won two bronze medals -- repeating a pattern of the past where the women were responsible for their medal haul.

Prior to Sun's performances in Shanghai, the only gold medal a Chinese man had won at the world championships or Olympics was when Zhang Lin won the 800 freestyle in Rome in 2009.

Yao however, said the reasons why the country's men's team were now starting to perform -- Wu Peng also won bronze in the 200 butterfly -- was twofold.

"Firstly, the height and the size of our men's team, if you look at our relay team, when they won the bronze medal, they stood next to other teams, they are as tall as their counterparts from the western countries," Yao said.

"We have some athletes whose heights are close to two metres. From that perspective, we are almost as good as other athletes from countries such as the U.S.

"Another reason is the overseas training programme," he added of allowing a number of swimmers to train offshore, something Wu said had benefited him while he trained at the United States.

Wu, who defeated Michael Phelps in two 200 butterfly races earlier this year to end the American's nine-year unbeaten streak in his signature event, said having to look after himself in the U.S. had been a huge learning curve.

"Training in the U.S is more relaxed, maybe it's due to cultural differences, in China the training is always very serious," he said before adding that in the U.S. he was required to take care of a lot of his own travel and planning.

"This is good training for swimmers."

Yao believed there were good coaches in China, something Wu recognised himself, but until there was greater depth of domestically-produced coaches they would continue to let swimmers train offshore and recruit foreign coaches.

"Chinese swimming is still relatively underdeveloped," Yao said. "Until we become a leading force in this sport, we will continue to send our swimmers abroad for training."

Despite their relatively successful performances, Yao said there was no indication of similar successes next year at the London Olympics.

"London will not be like the Shanghai world champs, they are different, not comparable," he said. "This time, we are at home, we have everything going for us.

"When we go to London, we will be facing many difficulties, (and) we must work hard and should not be complacent.

"Indeed, there are (still) many things we need to work on (and) our goal is to perform better than we did at the 2008 Beijing Olympics."

Gold China Silver London