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Blood Potential

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Jun 20, 2003
I am interested in a value that I would call ‘Blood Potential.’ It is basically the amount of time contributed to a static by O2 stored in the blood. All you need to work it out are your two best static times at two different lung volumes (e.g. TLC & RV)
V = larger lung volume
T = best static time at V
v = smaller lung volume
t = best static time at v
BP = ‘blood potential’
Note: T & t should be converted into seconds or fractions of a minute, e.g. 6:45 = 6.75 minutes or 405 seconds

BP = (tV - Tv)/(V - v)

Thus someone with a static of 5:50 with 7L lung volume and 1:48 at 1.6L would have,
BP = (1.8 x 7 - 5.5 x 1.6)/(7 - 1.6)
= 0.704
= 0:42
Therefore the oxygen in their blood supplies them for 42 seconds.
(This doesn’t take into account differing degrees of blood shift between inhale & exhale statics, but it is a good indication nevertheless).
My Blood potential is about 1:10, but I don’t know my volumes for sure. Has anyone heard of any stats that would give a BP of over 2 minutes? For example if Stefane Misfud (WR static) had a lung volume of 8L then he would need a static of 3:36 at 2L to have a BP of 2 minutes.
Someone shoot me down in this clumsy science, but I think there is definitely a value in there worth investigating.
According to my (very rough) calculations in order to set a WR with FRC freediving you would need a BP of minimum 3 minutes (fudging generously for blood shift & splenic contractions). Therefore Stefane would need 4:32 at 2L, without being able to improve his TLC time. If I had access to blood concentrations then I could work out what sort of Hg% this would require.
According to his website, Stephane Mifsud has a lung volume of 10.5 liters.... I suppose he packs...


I am a sprinter, i don't do any free diving but i am very interested in the physiology of the sport.

I was talking to a scuba instructor yesterday and he told me you guys use oxygen stored in your blood, on top of your lung capacity, to improve your static breath hold. I'm assuming this is what you are calling "blood potential".

What i would like to know is;

i) as part of your warm up/prep for a breath hold are there any techniques to increase the oxygen levels in the blood, breathing patterns or physical activity etc?

ii) can breathing excercises improve your "blood potential" over time and would you have any suggestions for a non-freediver. (i do have a static of 2:40)

Any help will be very much appreciated as i am thinking that an increase in "blood potential" could improve anaerobic threshold which is the main energy pathway for the longer sprints. I also know Linford Christie (100m olympic champion 1992) used to say he loaded his muscles with oxygen and he would run the entire race on one breath.

This may help or not. Here's the math with my numbers (Vr is a guess)
V = 7.25
T = 7
v = 1.6
t = 4
(tV - Tv)/(V - v)=BP = 4x7.25-7x1.6/7.25-1.6=3.15
I know Trevor Hutton once did an exhale static of 4'00", although it wasn't a forceful exhale (perhaps a 2-3L volume). His inhale static was around 6'00" to 6'30" and his inhale volume was only about 6.5L.

I think Sebastien Murat did 3'30 or 3'40 on a forceful exhale (volume 1.0 to 1.5L), and he was around 8'00"+ on an inhale of perhaps 9 or 10L.

However, the 'blood potential' calculation isn't necessarily an indication of O2 stored in the blood. A higher hematocrit means that you can stay conscious on a lower level of total O2 storage. So it gets complicated.

Concerning 100m sprints, I'm uncertain how much use extra oxygen would be in the muscles. Extra myoglobin would certainly be disadvantageous because myoglobin only exists in slow twitch fibers. 100m sprints are almost entired fueled by ATP, creatine phosphate and anaerobic glycolysis -- there is generally no oxidative phosphorylation, and oxidative metabolism generates power at a much lower rate anyway. Extra O2 stored in the muscles would probably make more of a differenc in a 200m or 400m race.

Eric Fattah
BC, Canada
I just did a few measurements of exhales and it looks like the volume for exhale static should be close to 3L and your BP figure about 2.
I should have pointed out that i am a 400m athlete. Therefore the main energy pathway is the anaerobic lactate (glycogen) system. This process transforms glucose into pyruvic acid to make ATP. If the muscle fiber has enough oxygen, the pyruvic acid enters the mitochondria for further energy use. But if the muscle fiber lacks sufficient oxygen, the pyruvic acid cannot enter the mitochondria and changes into lactate acid. Lactate acid will cause the muscles to "tighten up" and will also impare the breakdown of glycogen so dimininshing the available energy.
Due the the high intensity of a sprint this will take place at around 200-250m (as early as 25-30s which is well short of its potential of 90s). I was trying to find out if there are techniques i could use (as part of training and in the moments before a race) to increase the blood oxygen levels at the start of a race to increase the anaerobic threshold.

I am no expert, but I can tell you the standard freediving breathing to increase O2 in the body. We do diaphragm breathing for 2 to 4 minutes. That is we push the stomach out with the diaphragm and fill the lowest part of lungs first which have the most Alveoli in the lungs. Most adults don’t use this highly important part of the lungs, which is where you might find the most benefit in increasing blood O2.

After filling bottom of the lungs we fill the chest area of the lungs. We breath in fairly fast, without force and then make the exhales slower to lower the heart rate. Don’t know if lowering heart rate would help you.

50 seconds to 15 seconds before, most of us do purging breaths to lower our CO2. Purging breaths don’t increase O2. Purge breaths are like hyperventilation, except they are still full breaths using the diaphragm and done quickly on both inhale and exhale, but again without stress. It would be interesting to see if lowering CO2 before the start of a 400-meter race would have benefits. The thing to keep in mind though is that low CO2 with high O2 will cause dizziness and possible fainting, which would not be a good way to start the race. The blood vessels in the brain contract and lower the amount of O2 reaching it. You would have to experiment on how many purges, and if they had any benefit to you. Most freedivers are told to start with 2 or 3 when they begin.

Another useful thing might be a Pulse Oximeter. It’s a small device that attaches to your finger or ear and measures your pulse and O2 content of your blood. That way you would have some measurements on what methods increased O2 and to judge if high O2 helped your performance. Some readings through out your race and afterwards would very interesting as well. You can buy these over E-Bay for $300 and up. You can also do an internet search and find a lot of information on them.

This is my knowledge of it. Some will probably correct it soon.

You might want to try various 'apnea' exercises that freedivers do, such as apnea stairmaster, apnea walking, apnea running, and so on, which basically involve holding the breath (on an inhale or an exhale) while exercising. Doing so would improve your body's function to the anaerobic state you would experience at the end of the race. Your blood & muscles would be trained to store more O2/ATP/CrP, and your muscle buffers would increase (delaying the burn). Runners train in the weight room to load certain muscles beyond what they will ever experience in a race. Likewise, by putting your muscles in a state of hypoxia beyond what they will ever reach in a race, you would (in theory) gain a similar advantage as with weight training.

Be warned that hypoxic training is very stressful, even more so than standard 'anaerobic' training, so you need to load antioxidants, get lots of rest, train sparingly and watch for overtraining symptoms.

As far as what to do on the day of the race, you might want to increase your buffer levels via diet (i.e. lemon juice, green superfoods, eating figs, etc...). Superhydration might help since extra water dilutes acid (i.e. taking glycerol w/ H2O). Then, I would recommend a saturation breathing pattern before the race (i.e. inhale, hold for 5-8 seconds, exhale, inhale, hold for 5-8 seconds), taking care not to become too alkaline. However, most importantly, as every freediver knows, random body movements before a dive (or race) deplete stored energy. For that reason, I would recommend absolutely minimizing any body movements except the minimum required to walk into the starting blocks. Many athletes waste energy jumping on the spot and trying to 'stay loose.'

Eric Fattah
BC, Canada

Thank you for your replys. The examples you have given me are exactly what i was hoping for. I have plenty of knowledge on planning training programmes and will be looking how i can incorporate some apnea training into my cycles. I used to do some apnea training when i swam which improved my static breath hold but i have only just started to realise it could improve anaerobic threshold.

Also the race day preps you have suggetsed are ideal. I have used bi-carb to buffer before in training with good effect, i will do some research into the dietry suggestions you have made. Also the saturation breathing should work if i'm effecient getting into the blocks i should be able to continue breathing up until the 'set' call.

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