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CAPNIA — free dry apnea training app (beta, web version open for testing)

lievigz

Well-Known Member
Jun 17, 2007
2
1
86
CAPNIA is a dry apnea trainer:• CO2 and O2 tables, with a designer that recalculates the whole sequence
live as you set rounds, holds and rest reduction

https://capnia.app/

• Apnea Walk protocols by level, plus a custom builder
• Voice coaching for every phase, so you're not watching a screen mid-hold
• Live SpO2 and heart rate from a BLE pulse oximeter, plotted on the session curve and saved with it
• Technical guide: breathing biomechanics, hook breathing, CO2 vs O2 curves
• Session history, works offline, nothing to install

One thing worth saying plainly: the oximeter uses Web Bluetooth, which Apple
doesn't implement. On iPhone and iPad the app runs fine but can't read a
sensor. Android, Windows and Mac with Chrome or Edge do.
There's a simulated<br>mode if you want to see the telemetry without hardware.

It's in beta. Google Play closed testing starts 1 September, but the web<br>version is open now — no signup, no account:

Built for a tablet in landscape. Spanish, English and French.

SAFETY: these are DRY tables. Never do them in water, never train apnea in
water alone, don't hyperventilate. No app can watch you or pull you out of a blackout. If you're new to this, take a course with a real instructor first.

What I'd like to know: are the default protocols sensible? Anything missing<br>you'd expect? Does your oximeter pair? Tell me what's wrong with it.
 
I'm just starting a period of 'proper' training, so I'll give some of it a bash (I'm very unlikely to do any apnea walking). I've tried signing up for the official app beta testing, but if I'm not accepted for that I'll use the web app and report back here with any comments or suggestions. Thanks very much!
 
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One thing I'd like to see in a freedive app/watch is a one-breath CO2 timer. This is really simple - it's just a repeating timer that beeps once every set time period and then starts over again.
In a one-breath CO2 table you pick a time suitable for yourself - say for example 1 minute. You breathe-up and then hold for one minute, then exhale once and inhale again and hold for another minute - no rest period. Repeat. Do this for many periods to build up CO2 tolerance. Of special note: that there is no requirement for timing a rest/exhale portion - you are just doing a natural exhale and inhale. So this is just doing a VERY SLOW breathing period - breathe once for the period of your chioce. You just need a timer that beeps every period to tell you take do another breath.
And yes, I know you can just use the regular CO2 table found in many apps to do this, and I have done it that way
- you set a 1 second rest period and 1 minute hold period. And it sorta works but it's unnecessarily complicated and confusing when the voice/message is trying to voice the very short 1 second rest period right on top of the start of the hold period. Better to just eliminate the rest period altogether.
With a simple repeating timer you don't even need to set up a table - you just set a timer period and hit GO. Simple.
 
One thing I'd like to see in a freedive app/watch is a one-breath CO2 timer. This is really simple - it's just a repeating timer that beeps once every set time period and then starts over again.
In a one-breath CO2 table you pick a time suitable for yourself - say for example 1 minute. You breathe-up and then hold for one minute, then exhale once and inhale again and hold for another minute - no rest period. Repeat. Do this for many periods to build up CO2 tolerance. Of special note: that there is no requirement for timing a rest/exhale portion - you are just doing a natural exhale and inhale. So this is just doing a VERY SLOW breathing period - breathe once for the period of your chioce. You just need a timer that beeps every period to tell you take do another breath.
And yes, I know you can just use the regular CO2 table found in many apps to do this, and I have done it that way
- you set a 1 second rest period and 1 minute hold period. And it sorta works but it's unnecessarily complicated and confusing when the voice/message is trying to voice the very short 1 second rest period right on top of the start of the hold period. Better to just eliminate the rest period altogether.
With a simple repeating timer you don't even need to set up a table - you just set a timer period and hit GO.
Good thinking - I'd like to see this too.

In the meantime, there are some videos on YouTube that are useful for this - I've downloaded a copy of one that's one beep a minute for an hour, but I'm sure there are others. Alternatively, if you have access to PowerPoint it's really easy to make your own and export it as a video - I made my own tables this way for years. I also have an old MP3 file somewhere that someone gave me that has beeps that very slowly get farther apart for about 45 minutes, I think - you breathe on the beeps and don't really notice the change.

I'm sure you could get any of this customised very easily from AI, but having it in an app that tracks what you've done (and isn't limited to eight holds) would be really useful - especially if it also graphs the effect of the exercises on SpO2 and/or heart rate.
 
Good thinking - I'd like to see this too.

In the meantime, there are some videos on YouTube that are useful for this - I've downloaded a copy of one that's one beep a minute for an hour, but I'm sure there are others. Alternatively, if you have access to PowerPoint it's really easy to make your own and export it as a video - I made my own tables this way for years. I also have an old MP3 file somewhere that someone gave me that has beeps that very slowly get farther apart for about 45 minutes, I think - you breathe on the beeps and don't really notice the change.

I'm sure you could get any of this customised very easily from AI, but having it in an app that tracks what you've done (and isn't limited to eight holds) would be really useful - especially if it also graphs the effect of the exercises on SpO2 and/or heart rate.

Good thinking - I'd like to see this too.

In the meantime, there are some videos on YouTube that are useful for this - I've downloaded a copy of one that's one beep a minute for an hour, but I'm sure there are others. Alternatively, if you have access to PowerPoint it's really easy to make your own and export it as a video - I made my own tables this way for years. I also have an old MP3 file somewhere that someone gave me that has beeps that very slowly get farther apart for about 45 minutes, I think - you breathe on the beeps and don't really notice the change.

I'm sure you could get any of this customised very easily from AI, but having it in an app that tracks what you've done (and isn't limited to eight holds) would be really useful - especially if it also graphs the effect of the exercises on SpO2 and/or heart rate.

That’s a very interesting contribution, and I’m going to implement it because I’ve done that exercise many times myself. It’s actually a variation of the One Breath, which I’ll call 'One Breath Fast', where you set the breath-hold time and the number of rounds, with just an audio cue to signal when to take a breath. I will also enable HR and SpO2 tracking, and it will be saved in the history. :)
 
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Credit goes to the poster above me!

We sometimes do one breath per minute for ten minutes as a dry warm-up at my club. I'd be really interested in seeing the effect of doing it passive (or emptier) on SpO2 in particular.

I signed up for the beta testing, by the way, and have had an e-mail saying I've been accepted, so I'll follow the testing procedure, but will try to add anything I think is pertinent to this thread as well.

A long time ago I made a list of everything I'd like to see in an app, so I'll try to find that and let you know if there's anything I think you might like to add.
 
That’s a very interesting contribution, and I’m going to implement it because I’ve done that exercise many times myself. It’s actually a variation of the One Breath, which I’ll call 'One Breath Fast', where you set the breath-hold time and the number of rounds, with just an audio cue to signal when to take a breath. I will also enable HR and SpO2 tracking, and it will be saved in the history. :)
Awesome! Thank you!
 
I tried out the app at link above. When I select English as the language some of the app is in English but a lot remains in Spanish. There seems to be a problem with translation feature.
 
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