Sailors off the south coast of England will repel spray from swells using new water-resistant nanotechnology for their harnesses. Michael Phelps will compete in a swimming cap and goggles designed to minimize torque while moving through a pool. And some of the fastest people in the world will be donning uniforms with a dimpled texture imitating the exterior of a golf ball to make them go even faster.

Four years after a revolutionary swimsuit helped break 15 world records in Beijing, technological breakthroughs in myriad sports are again raising a probing question at the London Olympics: Are athletic edges cooked up in a lab as legitimate as those built through hard training?

“It’s a hard one,” said Philippa Oldham, head of manufacturing at the Institution of Mechanical Engineers in London. “Regulators have to address the question: Is it in the spirit of the sport? Yes, something can be approved, but if it can make people faster then it should be available to everyone to make it fair?

“It’s one of these things that everyone is keen to see what the new technology is, but once the records start rolling in, that’s when the debate starts.”

At the 2008 Games, 94 percent of the swimmers who medaled, including Phelps, wore full-body LZR Racer suits by Speedo, breaking so many world records that athletes and coaches began to cry foul. Their success led FINA, swimming’s governing body, to ban the suits in 2009. Olympic swimmer Ryan Lochte spoke out about the unfair advantages of the LZR suits at a news conference in London.

“Back then anyone could put on a suit and be fast,” Lochte said. “If I had it my way, I’d go back to old school when we were all wearing banana hammocks.”

The experience in Beijing has led to somewhat more caution in London. Many manufacturers have been working on innovations since the closing day of the Beijing Games, but sports engineers are now designing within parameters implemented by Olympic regulatory committees, which have prohibited certain advances out of fear of what many are now calling “technology doping.”

But retaining the purity of sports in the face of innovation has been an ongoing struggle and, purists say, a series of innovations ahead of 2012 still fall within a certain gray area. The new Speedo Fastskin3 suit, for instance, was created to work together with the matching swimming cap and goggles. Designed using 3D scans to create a flow of water around a swimmer’s body, the combined set appears to reduce drag by 16.6 percent in comparison with standard-issue equipment.

“Tech has a key role in the sport to keep it growing and evolving, but there needs to be a line drawn. We can’t turn athletes into super humans,” Joe Santry, research manager for Speedo’s Aqualab, said.

In addition, Nike’s Pro TurboSpeed uniforms, the official suits for the U.S. track and field team, have been proven to provide an edge to sprinters.

The new two-piece uniforms have been aerodynamically engineered with a dimpled texture to imitate the exterior of a golf ball and can shave up to 0.023 of a second more over 100m than Nike’s previous uniform. But what may seem like a miniscule gain can affect medal standings. For instance, that 0.023 second gain would have left US sprinter Walter Dix coming home with silver, rather than bronze, in the men’s 100m final in Beijing.

Steve Haake, director of the Center for Sports Engineering at Sheffield Hallam University in the UK, said that, like it or not, such innovation can make all the difference in close groups such as the 24 runners competing behind Jamaican Usain Bolt in the 100-meter sprint.

“Improvements are fair if these technologies are available to all athletes,” Haake said. “Where people don’t like it is if some countries are spending more money on research – a poor little country in Southeast Asia for example can’t do that.”

Andrew Wheating, a 1,500-meter runner who has been battling a foot injury, said the kind of spikes he wears for competition is very important. The fluorescent yellow Nike shoes he’s wearing for the Olympics are the fastest the company has ever come out with. Their weight is almost imperceptible in the palm of your hand.

“It’s a mental game,” Wheating said. “If I think it’s going to make me run faster then I’ll wear it.”