Forums | XtremeSpearfishing.com

Freediving Class in Fort Lauderdale!

2008-01-15T16:05:20-06:00

Yo anyone want to take this freediving class.... I can get us a discount if a few of us go toghether.

equalizing while freediving

2008-08-20T14:28:01-06:00

Hey there everyone - new to the board here. I have been spearing for a while, but just now getting more into freedive spearing. I dont have too much issue holding breath, but I seem to have more of an issue equalizing when freediving - maybe partly because my head is down below the rest of me. (whereas when scuba, I usually go down slower and feet first)

Has anyone else experienced this? Ideas?

Also a buddy and I have been thinking about doing the FIT class, do they work on equalizing in that class?

$10,000 donation in name of Dimitris Vassilakis for Freedivers Recovery Vest

2008-06-17T05:38:30-06:00

Michael Dewhirst a spearo from England has just donated $10,000 to
the Freedivers Recovery Vest project. Michael had a very close
relationship with Dimitris Vassilakis who died of freediver blackout
last September in Greece. Dimitris was widely liked and respected,
both in the spearfishing community and in the pure apnea community as
well.

Dimitris taught Michael to be a selective hunter, one more concerned
about the quality of his catch than how much meat he can put on his
table. Here is Michael’s dedication message:

“The loss of Dimitris Vassilakis was a terrible tragedy on a personal
and many other levels. He was my best friend and helped me massively
improve with my free-diving and spear-fishing. He taught me many
other things too. Those who knew him know what an amazing person he
was. Through this donation I hope to help the sport any way I can and
commemorate Dimitris.”

need a new gun

2008-05-15T14:48:32-06:00

I have been diving for the last year and have a basic spear gun right now. I am looking to buy another one but was looking for any good ideas on which one to buy.

Freediver Recovery Vest technical ideas

2008-06-17T05:31:48-06:00

The following post came from a discussion I have been following regarding some development ideas surrounding a freediver recovery vest. I found this interesting and figured I would share.

Upon reflection and comments by others I realized that the Mammalian Diving Reflex and the shunting of blood flow away from peripheral circulation to thorax & brain would complicate measurement.
I agree that a pulse oximeter on the earlobe sounds great.

At the surface we expect a partial pressure of oxygen O2 of 0.209.
We dive down to 66 fsw (20M) - 3 ATA - so if the ear clip works we expect roughly 0.600. As the seconds tick by the 02 drops and CO2 rises.
As we ascend O2 decreases from using legs to kick up but the PPO2 plummets as the ambient pressure drops with shallower depth.

We run on PP02 of .21, are impaired @ .16, lights out @ .12 or and death below .10. (or something like that, physiology was long ago)
At depth ambient pressure keeps PPO2 above the threshold so the lights stay on in our brain.
During ascent the PPO2 in the brain plummets. Somewhere between 30 fsw and the surface it may drop too low to sustain consciousness.
Lights out, shallow water blackout.
The Performance Freediving Class and seeing people Samba & SWB (under safe supervised pool conditions) was a real eye opener.

( let’s skip that PPO2 in lungs versus PP02 in blood to brain thing on ascent )

For an Oximeter to work it would need to be compatible with the Mammalian Diving Reflex and have an algorithm that checks depth vs. PP02 to know when to fire.

Best fishes & safe diving to all,

PeterV
Saint Petersburg, FL

PS. rather than re-invent the wheel, suggest ask NEDU if they know of an oximeter that works wet and at depth.