Little River - Out of Breath

[Jay]

Two things stand out. "tested somewhere between air and 32%".....That leaves a lot of room for conjecture. If it was closer to air then 32 it could be an item to evaluate. Unless someone is accustomed to diving those depths on air then narcosis is a concern. Particulary if you add in the work load.
I have a lot of past experience with diving air and 90' is the threshold for a lot of people, even with light work. Swimming without any pull-and-glide into LR is definitely work and the onset of narcosis goes up exponentially with work load.
Just the workload alone could be an issue. When swimming into heavy currents one should monitor their breathing to prevent just this type of occurrence - Increased co2 levels will give the impression that you cannot suck enough air through the reg.
As others have mentioned a person's physiology and mental/emotional state can be different from day to day.
There is also the "lead diver syndrome" which I have found my self guilty of many a time. Sometimes when you are the lead diver you set a higher pace then you would normally swim at yourself.
Yes, there are a lot of possible contributing factors but this is an example of why folks need to be aware of their breathing rate and workload at all times. The "I can't catch my breath" feeling is overwhelming and significantly reduces one's situational awareness and ability to respond to even the simplest of problems never mind emergencies.
I have put myself in that condition a few times over the years.

Thanks for sharing this!

[LCF]

Sounds like me in Ginnie Springs . . .

As has been pointed out, the amount of volume that has to pass through the gas exchange part of your lungs is determined by CO2 production. When you exercise, you make more CO2, and you have to move more air through your lungs. On the surface and without gear, it isn't too difficult to do that. But at depth, with the increased density of gas AND the resistance of breathing through a regulator, it gets more difficult. And as the drive to breathe increases, the tendency is to move toward a breathing pattern of shallow panting, and this adds to the problem, because most of the gas that's getting exchanged with each breath now is gas that was sitting in large bronchi, which don't participate in gas exchange. So your CO2 is too high, AND you aren't breathing in a way that gets rid of it efficiently. Add a bit of narcosis to augment the apprehension, and you have a recipe for panic.

A test my Full Cave instructor threw me was this: He told my "buddy" (who was another fully certified diver spending the day with me to create a team) to swim quite fast. He wanted to see that I would both be alert enough and assertive enough to tell him to slow down. (I passed, btw!) There is a safety component to this, as well as a comfort one.

Regarding the "lead diver" thing . . . I've also found that, if I'm dealing with something of my own, whether it's a gear issue or a mental issue, I'll go into default kicking mode, and that's a steady kick without a glide phase that is NOT the way I normally swim, and is much faster than I prefer to go INTO the cave. I wonder if something like that was happening to your buddy?

[stairman]

Being skinny and doing a physical labor job isnt enough to stay in shape. Even with the low flow, the depth and fast pace got him sounds like. Im known as a slow paced swimmer but didnt start out that way, I just found I like it better and am more efficient. Glad it ended up alright, the Florida Room will be there for the next trip.