Shark lesson.

A new suit designed by Speedo may help swimmers like Michael Phelps shave time off their race. That could mean snagging gold at this summer's Olympic Games in Athens, Greece. Called Fastskin FSII, the two-textured bodysuit imitates the skin of the ocean's top cruiser--the shark. Like any swimmer, a shark fights drag, a slowing force caused by friction (resistance to movement). To reduce drag between its body and the water, a shark's skin is covered with toothlike scales, called denticles. As the shark swims, water rubs only against the denticles' tiny tips. Since there is less friction on smaller surfaces, there's less drag than if the shark's skin were smooth.

Taking a lesson from nature, Speedo's suit uses two fabrics: One---called Fastskin--has pointy ridges like a shark's denticles, and covers areas like shoulders that stick out in the water. A smooth fabric, Flexskin, cloaks low-drag areas such as under the arms.

Will this artificial skin really pare down swimmers' race times? Phelps thinks so: "The suit will definitely help you get that extra 10th or 100th [of a second] that you really need to win a gold medal."

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Resources:

For more information related to this issue's new stories, check out the following Web sites:

Learn more about Speedo's high-tech swimsuit at the Speedo Aqua Lab Web site. Site includes swimsuit-testing results: www.speedoaqualab.com/jump.html

Keep up with this summer's Olympic Games: www.athens2004.com/athens2004/