What are they on? Or are they?

When Chinese swimmers started blowing rivals out of the water in London's Olympic pool, whispers quickly followed. Is China cheating the sport again, as it did in the 1990s, when drug-fueled, muscle-bound swimmers emerged from nowhere to beat the world? Alain Bernard, the 2008 Olympic freestyle champion from France, was among those who wondered.

"I'm for clean sport, without doping, and I truly hope the authorities in charge of this are doing their job in good conscience and really well," he said. "Unfortunately, I want to say that there is no smoke without fire. But today there is no proof to show that any Chinese has tested positive in this competition."

At a briefing Monday in London, reporters peppered Arne Ljungqvist, the International Olympic Committee's medical commission chairman, with questions about Ye Shiwen, China's 16-year-old swimming sensation. Ljungqvist said "it is very sad that an unexpected performance be surrounded by suspicions."

"Suspicion is halfway an accusation that something is wrong," Ljungqvist said. "I don't like that. I would rather have facts."

Unlike the 1990s, however, there are plausible explanations this time for why China is the swimming phenomenon of the 2012 Games.

For example, Ye's astounding world record in the 400 medley, when she swam the last 50 meters faster than American Ryan Lochte did in winning the equivalent men's race, isn't solely attributable to her large hands and feet. It also is at least partly because China, which has grown to become the world's second-largest economy, now throws big checks at some of swimming's sharpest minds. China has turned to foreign trainers to get their coaching programs, expertise and methods, not only to hone its swimming stars but to make them more rounded and relaxed, too. The idea is that happy swimmers are fast swimmers.

Ye has trained in Australia with two well-recognized coaches, Ken Wood and Denis Cotterell. Wood has had a contract with the Chinese Swimming Association since 2008, and 15 of China's swimmers in London, plus five of its relay swimmers, have trained at his academy north of Brisbane, rotating through in groups for a couple of months at a time, he told The Associated Press in a phone interview.

"I get paid per month, per swimmer four times more than I do with my home swimmers," Wood said from Australia after Ye qualified comfortably fastest Monday in the 200 medley heats. China pays him bonuses for Olympic gold and for swimmers' personal bests, and he also got a bonus for Ye's 200 medley world championship win in 2011.

"China is putting a lot of money into its program and I am only too happy to work with them," he said. "The whole Chinese philosophy is that they want to be the best they can."

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