Mammalian Dive Reflex

[KnottedYet]

I just don't put my face in the water...

...seriously.

I've always swum with my face out of the water. I'm a slow swimmer anyway, so it doesn't matter. Mine is more a panic. Had a bad experience diving once (rip-tide, clinging to a rock, running out of air) and really get perturbed if my face is under now.

MDR slows the heart rate, reduces bloodflow to the extremities, etc. What you describe sounds more like a panic. The active reflex is to help us survive under water, it doesn't make us fight to get out of the water. MDR is what makes itty-bitty babies so calm and happy underwater.

Here's an abstract: http://www.springerlink.com/content/l831603655v86219/

Here is a paper by some folks who posit that the MDR's slowing of the heart rate could somehow be used to help calm a racing heart rate. http://www.sciencedirect.com/science...c&searchtype=a

I can't get the full text of this one, but it talks about how emotional arousal can counteract the calming and heart-slowing effect of the mammalian dive reflex - that would be the panic you and I experience which prevents us from experiencing a proper MDR. http://onlinelibrary.wiley.com/doi/1....cp020325/full