"The Master Switch of Life."

January 4, 2015 8:57 AM

Your Body's Amazing Reaction to Water: The strange physiological effects of freediving.
posted by quin (21 comments total)

As on the moon’s surface, gravity on the seafloor still exists below forty feet but is greatly reduced.

"science" huh
posted by neckro23 at 9:19 AM on January 4, 2015 [10 favorites]

"As on the moon’s surface, gravity on the seafloor still exists below forty feet but is greatly reduced." I'm pretty sure there are better ways to explain the effects of buoyancy.
posted by Mei's lost sandal at 9:20 AM on January 4, 2015 [4 favorites]

Owe you a coke!
posted by Mei's lost sandal at 9:21 AM on January 4, 2015

Yes, gravity not existing or being reduced underwater would be a MUCH bigger discovery than left-over aquatic behavior.
posted by blue_beetle at 9:28 AM on January 4, 2015 [3 favorites]

They don't call them 'SED' Talks for a reason.
posted by leotrotsky at 9:29 AM on January 4, 2015

Interesting stuff - I enjoyed the video at the very bottom (about reef species and the use of rebreather systems at 300-500ft) even more.
posted by stinkfoot at 9:37 AM on January 4, 2015

More science grumpiness:

So Boyle's Law describes the behavior of ideal gasses and makes absolutely no claims about human physiology. Just because your lungs hold a 'fixed' volume of gas doesn't make them obey Boyle's law directly when the pressure changes. To claim that "Boyle's law [...] appeared to fall apart underwater" is misleading. It doesn't help much either when it's put in a "those silly scientists!" tone and emphasized with a red background in giant text.
posted by TimeStove at 9:58 AM on January 4, 2015 [8 favorites]

Yeah, your lungs are attached to the inside of your chest.
posted by fshgrl at 10:13 AM on January 4, 2015

Also, perhaps this "master switch of life" business has some validity, though it's really not clear what it means even in context, but whatever that refers to is totally inadequately characterized here.
posted by clockzero at 10:26 AM on January 4, 2015

The ideas are interesting, but yeah, I hate the tone of TED talks and articles. It also doesn't really get into the supposed life-prolonging effects of being underwater beyond one mention.
posted by limeonaire at 10:45 AM on January 4, 2015

There's been some earlier discussion here that might suggest one core problem the body has to solve with exertion is the management of waste heat. I'd suspect that immersion in water that's cooler than body temperature (or surrounding air) dramatically changes the management of that problem; maybe that's what's behind this?
posted by weston at 10:48 AM on January 4, 2015

The whole thing reads like he's gearing up to try and sell some sort of quack medical device.
posted by sobarel at 10:55 AM on January 4, 2015 [3 favorites]

Now introducing The Master Switch of Life™, available now for 3 easy payments and 1 fucking complicated payment of $19.95.
posted by stinkfoot at 11:17 AM on January 4, 2015 [1 favorite]

So air was the problem, all along! And we blamed tobacco!
posted by Segundus at 11:50 AM on January 4, 2015 [1 favorite]

As on the moon’s surface, gravity on the seafloor still exists below forty feet but is greatly reduced.

Shouldn't be hard to calculate the reduction in gravity caused by being 40' closer to the Earth's core. I doubt the actual reduction deserves to be called 'great'.
posted by straight at 11:58 AM on January 4, 2015

Shouldn't be hard to calculate the reduction in gravity caused by being 40' closer to the Earth's core. I doubt the actual reduction deserves to be called 'great'.

Actually the force of gravity increases as you descend in the ocean because the earth is not a sphere of uniform density. The core has a much higher mass density than ocean water, so as you move closer to the core, the force increases.
posted by JackFlash at 2:52 PM on January 4, 2015 [1 favorite]

previously?
posted by subversiveasset at 4:18 PM on January 4, 2015

I'm intimately acquainted with the mammalian diving reflex. I experience episodes of tachycardia, where my heart rate doubles, and cold water on the face is one of the effective responses (also Valsalva maneuver and medication. see a doctor if this is pertinent). It's also quite effective for panic attacks, which I experience, as well.

The article is really classic internet click-bait-y. Thanks for the Boyle's Law clarification, timestove; that was bugging me but probably not enough to look it up.
posted by theora55 at 8:20 AM on January 5, 2015

The article was so illogical it gave me a headache.
they used less oxygen and therefore could stay underwater longer. Longer than what?
Bucher could survive up to three times longer in water than they could in open air - Um, what?

If this stuff is written up somewhere sensible by a logical person I'm sure it would be a very interesting read - can anyone point out such?
posted by glasseyes at 10:06 AM on January 5, 2015

They used less oxygen and therefore could stay underwater longer than if they didn't and thus had to come up for air.
Bucher could hold his breath up to three times longer in water than they could in open air.
posted by effugas at 10:14 PM on January 6, 2015

It's not the worst thing in the world to explain the effects of gravity are reduced under water, and that moving around bears some resemblance to moonwalking. Gods, are you guys angry there's no equations too?
posted by effugas at 10:16 PM on January 6, 2015