Pharyngula

Posted by: Paul Burnett | September 6, 2011 9:34 PM

The diver couldn't use flippers, the way his ankles/feet are articulated - he's pushing (like pedaling) rather than using his feet like fins.

Posted by: mrpoxman | September 7, 2011 1:01 AM

I used to body surf for hrs in large swell and hang out the back with surfers no problem all year round (I would drown in 10 min now) It's amazing what you can do when your fit and well adapted to something.

Posted by: Fred The Hun | September 7, 2011 3:24 AM

You are required to hold your breath while you watch this entire video

And pedal a stationary bicycle at the same time...

BTW it is interesting to see him walking along the bottom, though one doesn't know how buoyant his spear gun is, he obviously doesn't have much fat on his body and the amount of air in his lungs has been significantly compressed by the 3 ATM of pressure at 65 ft of depth thereby reducing what little buoyancy he may have had to start with.

Contrast this means of getting lunch with the average obese USian sitting for 15 minutes ensconced in a couple thousand lbs of steel, burning fossil fuel in the drive through to Mickey D's to purchase a chunk of industrially produced, ground up cow.

Posted by: jonbob0008 | September 7, 2011 4:57 AM

I was able to hold my breath long enough, but while I was sitting comfortably in a chair, this guys was swimming, walking and moving around. My oxygen usage was far less that his.

Still impressed that I was able to do it, though. :)

Posted by: jack.rawlinson | September 7, 2011 2:33 PM

I got as far as 2:30 when I was younger and curious about training myself to hold my breath. But that was sitting still in a chair at one atmosphere. This is way more impressive.

Posted by: RaulFelix | September 7, 2011 8:17 PM

"...perhaps the idea of humans living as marine mammals is not so far-fetched after all". Is BBC preparing to push the Aquatic Ape Theory?

Posted by: marc verhaegen | January 27, 2012 6:51 PM

Human Breath-Hold Diving Ability Suggests a Selective Pressure for Diving during Human Evolution
Erika Schagatay 2011:120-147
Abstract:
Modern humans are generally considered to be fully terrestrial, yet display a range of activities involving breath-hold (apneic) diving, including sustained harvest diving, spear-fishing, recreational free-diving and competitive apnea for duration, distance or depth.
Via harvest diving, involving repeated diving with half of the time submerged for several hours per day, groups in SE.Asia obtain a considerable amount of catch.
The physiological basis for such repeated diving involves
i) conscious breath control,
ii) an efficient diving response, diverting stored oxygen to the heart and brain,
iii) adequate thermal insulation.
Another contribution to the human diving ability comes from the spleen, which - by ejecting extra red blood cells into circulation - can enhance blood gas storage and CO2 buffering capacity, a response typically found in seals.
Most striking among human aquatic activities is competitive apnea, with records of a period of 11 min 35 s in duration, the distance of 265 m in underwater swimming with fins, and a depth of 124 m in deep-diving with fins. Without fins, the distance of 218 m and depth of 95 m have been achieved, performances in the range of marine mammals.
This requires additional mechanisms to maximize gas storage, minimize energy expenditure, and enhance conscious tolerance to asphyxia, involving e.g. increase lung volume, baseline hematocrit and spleen volume, and means to cope with the increased pressure. While it takes both inherent predisposition and training to achieve such record results, most healthy humans can, after some practice, make voluntary apneas of 3-4 min, swim a distance of 50 m under water and reach depths of 20-30 m, which may be unique among terrestrial mammals.
Human superior harvest diving and competitive diving capacity may suggest a selective pressure for diving during some time period of human evolution.