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Bo - Why?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Aug 27, 2002
At last. He got me!
Week ago at the 1st Slovak freediving championchips
I experienced my first BO.
What I want to know is why it happened. I'd be very thankful for your coments.
This is my analysis:
Preperation (as always):

10,00 breathe up (slow exhaling lying on the back)
1,10 residual static (usually 0,45-1,00)
1,40 breathe up (slow exhaling)
1,40 residual static (usually 1,30)
2,00 breathe up (slow exhaling)
2,05 residual static (usually 2,00) - slight SAMBA!!!?
3,30 breathe up (slow exhaling, I was moving to the starting place)
2,30 1st contraction
3,35 10 contractions
4,00 15 contractions
4,15 BO!!!

I wasn't pushing too much. I was counting contractions and everything went as always and then ... I felt asleep!

My PB is 5,08 (water) and 5,44 (dry). I was always able to hold 30 -35 contractions. My 1st comes around 2,30-3,30.
What went wrong this time?

I think the main cause was that Samba in preparation with too little time left for the recovery.
The water was too cold (I was shivering and couldnt relax properly) and there was awesome humidity on the pool. Best static overall vas only 4,46.

Thanks for replying...

many people believe that having a samba will predispose you to having another soon after. personally i believe this to be true. so that slight samba you had during your warm-up may have been a contributing factor.

i would forget about counting contractions. i don't think this is a helpful thing to do - because you end up trying to use it as a gauge, i.e. "15 contractions - i'm safe. 20 contractions - time to come up"...

it's best to focus in on how you're feeling. if you did this, rather than counting contractions, then you probably would have realised that you needed to come up.

I believe in" focus how im feeling" than counting contraccion

when we make a building we dont' start from the top....but with the foundation....

that's simple- if you do 25 m in dinamic don't try 50 m?? try 2 or 3 meters more when you are ready for it...but concentrate in creating a foundation first....and take your pulse at certain distance..It let you know how your body is responding...

what else to say...also if you yperventilate - or do some strange metodo for breathing probably you will never know when to stop..what it mean that your feeling in such case will not help you.. ...... there are to many factor...so is better to start with the basis




Prayer is the Oxigen of the soul
Last edited:
I had a similar experience a few months ago. I was doing statics and had agreed with my buddy to give signals every 15 seconds after 2:00. The last thing I remembered was giving him a sign at 2:45, though he said I gave good signs at 3:00 and 3:15!! The following things were told to me by my buddy. At 3:25 I tried to get to the surface, gripping the side of the pool very tightly, then my hands went limp. He turned me on my back and saw that I was unconscious, with eyes open and a blank expression. I started breathing immediately without any trouble and came round within seconds. When I came round I did not feel ill, confused, or anything else bad.

I think the cold could be a major factor in these things - a huge amount of oxygen is wasted by shivering.

O'boy, what was your blood pressure like? Were you dehydrated? Sleep the night before?
I believe Alun is right, but that the samba may be an indicator that you are more susceptible at the time to have a BO, rather than the cause.
Erik Y.
  • Like
Reactions: OceanSwimmer
This one is a classic!

Pre-competition stress in many athletes tends to cause a greater blood shunt (fear response, not diving response). This worsens the effect of ventilation or hyperventilation, so what normally might have been ventilation has the effect of hyperventilation. This means you can end up hypocapnic. In my case, every single competition I have been at, I have been forced to breathe much less, and more slowly, than during training, for this reason.

So, problem #1: your ventilation pattern combined with the fear response made you hypocapnic. This is why your exhale statics were longer than usual, and that is probably why you pushed the last exhale static to samba.

Once you samba, your brain glutamate level will be increased, and your gaba level decreased, an effect which can last for hours, predisposing you to an earlier samba/BO in a subsequent performance.

Problem #2: Samba in warm up predisposed you to earlier 2nd samba/BO.

So, a combination of hypocapnia and the samba in the warm up was probably it. Of course, if you were dehydrated, colder than usual, etc.., these and others things could screw you up as well.

A samba/BO is always a good learning experience, if nothing else.

Eric Fattah
BC, Canada
interesting points Eric.
I read somewhere, that you prefer to have LMC before your max. attempt. so do you think, that the advantages of warm up sambas (stronger MDR?) outweight the negative effects?

Thanks a lot. Hope that I woun't be the only person who will learn from this experience.

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