Should Michael Phelps improve his finger-swimming techniques?
July 28, 2012
While watching the swimming tournament at the London Summer Olympics, take a good look at the hands of the competitive swimmers! For, new research finds that this hand position creates an “invisible web” of water that gives swimmers more speed. Now, should Michael Phelps improve his ‘finger-techniques’?
Researcher Adrian Bejan, a professor of mechanical engineering at Duke University reports:
“It is a counterintuitive idea, the fact that you should paddle with a fork, not with an oar.”
However, the 2012 study was preceeded by a 2009 study which had already pointed out why most swimmers spread their fingers while swimming (see the picture below – describing how water flow varies for different finger positions).
Webbed feet and hands, of course, are a common trait of swimming animals from frogs to whales. In human swimmers, the invisible web of water allows them not to propel themselves faster, but to better lift themselves out of the water. That’s where the speed comes from, Bejan said. Swimmers push against the water’s surface not unlike South American Lizards, which can scamper on top of water by slapping their big feet against the surface. This force propels the swimmers out of the water, where they then fall forward, generating a horizontal wave.
“The higher you are above the water, the faster you fall forward and you see this effect in greater speed,” Bejan said.
With ideal finger spacing, the forces a swimmer can exert are 53 percent greater than those produced with no finger spacing, Bejan and his colleagues reported online June 9 in the Journal of Theoretical Biology. For aspiring swimmers at home, the perfect spacing is between 0.2 and 0.4 times the diameter of the finger itself.
The findings could have implications for better swimming robots and propulsion systems, Bejan said. They’re also handy for those trying to beat personal bests in the water.
What do you think: should Michael Phelps improve his finger-swimming techniques… in order to make another golden- paddle?