Laminar,
FRC recovery times for me(when I don't push the dive) appear to be so short as to be down right unbelievable.
Connor
What I initially found a little frightening about recoveries on FRC dives was that it seem that within seconds I was ready to dive. Even on a hypoxic dive, recovery appears to happen quickly, since I feel you don't totter on the edge of samba nearly as easily or suffer from as sudden a drop in blood pressure when you surface.
So there's the perception that perhaps you weren't as hypoxic when in fact you could have been even more hypoxic but more blood shifted and less predisposed to losing consciousness.
This is what it feels like to recover:
- long recreational dives: surface, a long hook breath, and then a few deep breaths, pop the snorkel back in and breathe as needed and within about 30 seconds I'd feel totally normal.
- performance dives: surface, hook breath, a couple of deep breaths and boom! burning legs for a couple of seconds, and then 30 second recovery and feel normal again. Probably fatigue still in arms and legs and then of course I'd sense that a much longer recovery was required 5-15 minutes.
I have not yet blacked myself out on FRC.
However, after each example, if I tried to dive too soon after, I would soon feel hypoxic or even acidic (not in a good way).
I don't think there's a set ratio.
I worked it out a rough guide by doing about 3-4 weeks of solid 10-15m dives on FRC when I was first starting out. Seeing what recovery and time at depth ratio (by feel, mostly) worked best. Suddenly, when I figured it out, my times jumped dramatically - all without pushing to contractions.
In terms of performance oriented training on FRC, there is still so much to explore, but I'm confident that we will see performances that get very close to distances on full inhale and packing within the next year or so.
200m dynamic with monofin
100m constant weight
80m constant no fins
7 minutes static apnea+
16 x 50m in a decent time
etc....
I've been training in the pool again on FRC and finding significant differences in terms of sensation but in many ways similar parameters (or better).
To address recovery:
When I'm diving recreationally between 10-30m and 1'30 - 2'00" or so (no contractions), I generally wait about 3-5 minutes before the next dive for the longer and deeper ones. A bit less 2-3 minutes for shallower ones. I could easily maintain 1:1 in the 1'00 - 1'20" range and still feel pretty relaxed, I think. I figured out the 3-5 minutes mostly by feel in the very beginning, rather than searching for a specific ratio.
The key is to be patient. There is a lot of value in my opinion on using a natural sub-neutral breathing pattern as much as possible (no overt ventilations or purges) and that often means a longer rest. Others use a bit more aggressive breathing (Eric, at times) to compensate for cold and other factors. We have to always allow for individual differences and new approaches to this style.
So my advice is to set yourself a reasonable depth floor 10-15m, so that if you do feel hypoxic your time to get to the surface is short. Also, by having the same depth on each dive, you can be more finely tuned to the differences in effort, C02, low O2, dive response (which is what makes you get better and better with FRC), and mental state and how your body reacts to all this.
Remember that your acclimatization or adaptation to FRC should be about initiating a powerful dive response or dive response over a long session or many times a week. Better yet, aim for all three.
A dive response is what will make this work for you. Also you don't need much more than 4-5m to train for excellent chest flexbility, which is quite surprising. I'd say that 4-5m is the minimum, but 10-20m is ideal.
When you start to exceed old inhale+packing personal bests, that's when things start to get interesting. :t
Pete
