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Tillbaka till Fysiologi

Breathhold
Static apnea measurements
text: Sebastian Naslund
Second test; seven sambas - 7 min test

HOW TO STOP? I have several times had samba or blackout during static competition. My will to hold my breath blocks out all the uncomfort and the signals of low oxygen and high carbon dioxide. I also focus so much on relaxation that I don´t "wake up" in time.
The test below is to find out measurable signs that could make me terminate a breathhold in time. The test consists of a 6.30 min.sec breathold on land, lying on my back. My theory is that I could via my pulse or the rate of contractions find a way to bail out.

I have measured:
- Time (minutes and seconds)
- Oxygen saturation in the blood
(circulation from the heart).
- Pulse (average during 15 sec period).
- Number of contractions.
- Rate of contractions (per minute).
Time
oxygen%
pulse
contraction rate
# of contractions
0.00
99
74
-
-
0.15
99
74
-
-
0.30
99
74
-
-
0.45
99
74
-
-
1.00
99
74
-
-
1.15
99
74
-
-
1.30
99
75
-
-
1.45
99
76
-
-
2.00
98
77
-
-
2.15
98
79
-
-
2.30
97
81
-
-
2.45
97
83
-
-
3.00
96
85
-
-
3.15
94
82
-
-
3.30
92
79
-
-
3.45
90
75
6
1
4.00
88
71
6
-
4.15
85
64
8
3
4.30
82
58
10
5
4.45
79
50
15
7
5.00
75
50
20
9
5.15
70
51
22
14
5.30
65
43
22
20
5.45
59
42
25
25
6.00
52
42
28
31
6.15
45
40
30
38
6.30
42
39
30
46
My goal was 6 minutes. I stoped when I (in the corner of my eye) saw the oxygene meter reading 40 something. Finished with focused eyes, four deep breaths and an OK sign. Never lifting head from the floor though.

QUESTIONS ARISES
(Check terminology here)
The contractions rate, we know, are influenced by the rising carbon dioxide. Thus they mainly tell me how much I ventilated before breathhold. We know that high carbon dioxide increases blood flow to the brain and thus increases the tolerance to low oxygen..
This means that less ventilation, theoreticly leads to higher tolerance of hypoxemia. But it will give you a less comfortable breathhold and the symptoms of carbon dioxide might make you terminate your breathhold before you suffer hypoxemia.

CONCLUSIONS
Question is; has the rate of contractions anything to do with low oxygen? Has low pulse anything to do with low oxygen? P. Lindholms (Karolinska Institutet 2002) thesis claims that "hypoxemia... provides an additional but not principal stimulus for bradycardi".
Thus low heart rate can be a sign of low oxygen.
My conclusion is; by studying your individual pulse you can get a hint of when to terminate a breathhold. It has also been proven that low oxygen enhances the effect of the contractions - this contains some logic - that the body more violently tries to make us breath when we are low on oxygen.
Thus more violent and maybe also more frequent contractions can be a sign of low oxygene.
So if you have the same breathingpatterns before every breathhold the rate of contractions and the strength of them can be used to "measure" your status.


RED - Oxygen BLACK - Pulse YELLOW - Contraction rate

PREPARATION
Some readers might be intrested in the preparations to this breathhold.
Only water, honey and banana during the 12 hours up to TOP. Vitamin pill and a drink containing aminos, sugar and minerals.
One hour yoga and relaxation right before.
Breathhold empty lungs -
1 min.
3 min rest.
Breathhold full lungs
4.15.
4 minutes rest.
Breathhold
4.35.
8 minutes rest.
(last two breatholds with one minute of contractions in each).

BREATHING PATTERN
the last 3.30 up to top.
time
type of breath
rate of breath
pulse
3.30
L - L
4/ min
74
3.00
L - L(half)
4/ min
74
2.30
L(Half) - M - M
5/ min
74
2.00
L - M - M - L
8/ min
78
1.30
S - M - S- S - S - S
12/ min
78
1.00
L - S - S
6/ min
72
0.30
M - M - L(90%) (through nose)-
packed 8 gulps to 110% lung volume.
6/ min
72

This breathing was not planned. I just had an ambition to ventilate more than ususal to be able to experience low oxygen levels. At the same time I sought to keep my pulse down. I had some notions of hypocapnia.

Type of breath
lungvolume
breath lasts
description
L
90% - 35%
15 sec
Quick in slow out
M
80% - 25%
5 sec
more forcefull
S
65% - 40%
5 sec
very light (normal)

SUBJECT DATA
VC (6.8liters) (2002june)
RV (1.9liters) (2000june)
WEIGHT (70kg)
LENGTH (1.87 meters)
none-smoker

Second test; seven sambas

comments:
sebastian @ webvideo.nu