BEAVERTON, Ore. — Nike is allowing seven of the Olympic hopefuls it sponsors to don Speedo International's new full-body swimsuit instead of the Nike product for the U.S. Olympic Trials in Omaha later this month.

Nike spokesman Derek Kent said the exception is a limited one to allow top swimmers to experiment with other products, satisfy their curiosity and compete without distractions. Since the February launch of Speedo's sleek LZR Racer, swimmers wearing the suit have broken 38 world records, but not without some fuss.

Non-Speedo-sponsored athletes clamored to wear it. Italian swim coach Alberto Castagnetti accused Speedo of technological doping.

Tyr Sport Inc., a Huntington Beach, Calif., swimwear maker, sued Speedo in May, alleging that Speedo conspired with the U.S. swimming federation to stifle competition and lure top athletes away from other sponsors.

British-owned Speedo says the lawsuit is baseless.

Meanwhile other manufacturers rushed to redesign their suits to keep their swimmers happy and keep their logos above water and visible during the Olympics in Beijing.

The International Swimming Federation (FINA) has approved suits recently redesigned by Germany's Adidas AG, Arena Italia and Mizuno Corp. of Japan.

There is no independent proof that Speedo makes swimmers speedier.

Speedo says it worked with NASA, using a fabric thought to reduce drag and a design that incorporates seam-free construction and polyurethane panels.

San Diego State University sports physiology professor Brent S. Rushall, a critic of full-body suits, doubts it. Speedo has promulgated dogma as propaganda in an effective manner, he wrote on an Internet site.

Rushall chalks the 38 records up to other factors, including improved training techniques and Speedo's stable of top-ranked swimmers such as Michael Phelps.

But it might be working.

In performance swimwear, Speedo's market share has increased 7 percentage points year over year to 61 percent, said Matt Powell, an industry analyst with SportScanInfo. Tyr, at 20.6 percent, and Jantzen Inc. at 11.5 percent, both lost market share over the same period, he said.

Powell said he could not immediately cite Nike's market share.

"We feel there's been some positive momentum generated because of LZR Racer," said Craig Brommers, Speedo's vice president of marketing.

For now, Nike is simply allowing its seven sponsored swimmers, Brendan Hansen, Aaron Peirsol and Whitney Myers among them, to wear the Speedo at the trials instead of the Nike Swift swimsuit.

He declined to say if that permission would extend to the actual games or if Nike is redesigning its own Swift swimsuit.

"We're continuing work with our athletes to get their feedback on the product and fine-tune it," he said.