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Question 25 meter intervals

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Oct 4, 2019

Looking for input regarding 25 meter intervals with fins.

  • I am in a pool without a dive buddy and generally no lifeguard so I am keen on not finding my limits (i.e. being dead). As background, my static pb is 5 min and my best dynamic with fins is 75 meters.
  • I generally do 1 interval every minute which equates to generally 1:1 hold/respiration (25-30 sec hold / 30-35 sec breathe)
  • I am up to doing these for an hour and thought I should research what is happening with my o2 levels over time in this scenario but could not find any info.
  • I enjoy doing these and like the specificity of the intervals but thought I might get input from the interweb.

And of course I would prefer to have a dive buddy each day but I have yet to find a training partner in my neck of the woods so my goal is to be as conservative as possible while still in the water given that reality.
We do similar exercises as training for UWR/UWH and I do them by myself sometimes at the local pool. You can approach each 25m with the question of what do you want to develop....

- fast/slow swim, rest, go on the minute
- fast/slow swim, x number of breaths, go again
- fast/slow swim, surface swim to recover, go again
- max number of lengths in a set time... etc

There is always the safety net that you can just surface at any point and take a breath, which I would not consider a failure, as well as having the lifeguard at the pool. But I agree, by yourself is probably not the time to try to set records.
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The general rule of thumb is a ratio2 breathing for 1 hold for spearfishermen. Shortening the surface time too much is a major cause of SWB. Keep in mind that by the end of your workout your body is much less sensitive to low O2/high CO2, so the longer the training session, the less likely you are to recognize the edge.
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Hello all,
I can't really answer your question I am afraid but was wondering if perhaps anyone could help me out. I am relatively new to the UK and desperately trying to find a pool to do some dynamic training. Does anyone know of a pool in the Plymouth-Devon-Cornwall area that will allow that?

All the best
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