"What the #*%^?" is a common question heard every year from hundreds of bobbing heads attempting the famous Alcatraz swim across San Francisco Bay; arms and legs flail furiously, but it seems they're no closer to the beach.
The government has an explanation for this swimming phenomenon: You suck!
It's spelled out in this month's Popular Mechanics. "Humans are terrible swimmers, converting roughly 3 percent of their kicks, strokes and general underwater exertions into forward motion. We can boost our efficiency to 10 percent by adding fins, but dolphins, by comparison, can turn 80 percent of their energy into thrust."
Fear not, the government has a program to make it all better, or at least for those who swim in the line of duty. The video below shows the old way--Pentagon brains want SEALs to do it the new way.
DARPA, the Defense Department's R&D wing, is working on a contraption that allows Navy SEALs and others to swim 150 percent faster and with less effort than they would with regular fins. A rubberband airplane-looking thing, the PowerSwim is kind of like Rube Goldberg meets Aquaman.
Appearances aside, it aims to replace the flutter kick with something resembling a dolphinic undulation, causing a hinged foil to oscillate while a "propulsar foil" cuts the water along side. The approach to swimming is similar to that exhibited by many fish and aquatic birds, according to the DARPA Web site, "more than 85 percent efficient in conversion of human motions to forward propulsion."
Still, there's no free ride--as in a battery pack. The gadget requires muscle work and training. "The swimmer is essentially relaxing into a slightly bent position, instead of forcing or pushing the foils through the water," DARPA's Barbara McQuiston told the magazine. "This takes the emphasis off the small muscle groups used to kick, and allows larger muscle groups, such as the glutes and quads, to take over."