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Actual depth conversions?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.


Morone saxatilis
Mar 8, 2003
Okay, I've never been in water where I've had a chance to drop deeper than 45'. I have just moved though and now need to be able to make drops to ~110' or so. I've done no training but practice static breath holds in bed and have hit 4 min. but can always make 3 after warming up.

I also just took the freediving fins to underwater hockey and swam 75m w/out pushing myself too hard. I kicked at around 50% speed I would guess. Is it easier to go deep w/ negative bouyance or easier in the pool w/out having to equalize (plus psycological)?

So what's the optimal kick rate (long and slow but...) or whats the optimal usage of O2. Is there an amount of time that it should take me to do each 25m length?

I also think my breathing may not be optimal.

My question is what safe depth can/should I attempt w/ these numbers. Also what surface interval must be obtained to keep from saturating the body w/ CO2?
Hi defothecrown

Vertical distance is not the same as horizontal because of preasure effects on lung volumne ( among other things). 45 to 110 is a very big step. Your numbers sound like you have the capacity, but take it slow, real slow. I made a similar, but smaller step last summer and it was more than a little strange. You will find that the rules seem to change around 70 ft and will take some getting used to. You might want to consider a freediving clinic. Especially, this is very tight buddy system country.

Have fun with the transition, Connor
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The questions you have asked are related to training. To start with, I would advice to team up with another freediver, or search someone to teach you the right breathing and kicking techniques, since it is a bit difficult to learn those from the computer screen. Training together isn’t only positive from the safety point of view, but also for learning and sharing better techniques.

Your first question, or better group of questions, was if it is easier to go deep with negative buoyancy, or if it is easier in the pool without having to equalize and from a physiological point of view.

Well, the term ease is a bit difficult in this sense. Diving into the depth or swimming dynamics in the swimming pool are quite different disciplines, both from a physiological as physical point of view.

With dynamics in the swimming pool, there is the physiological safe feeling of being close to the surface. This safety is nevertheless very relative, because without an assistant, dynamic can still turn into loss of motor control or black-outs with serious consequents. This risk is larger after hyperventilation and can surprise the safety diver due to its fast development and unexpected severness. In some individuals, depth fear could be replaced by wall-fear.

Also from a physical point of view are the two disciplines quite different. Diving into the depth does have its disadvantage of equalizing, but positive buoyancy at the end of the dive makes the last part of the dive less difficult in comparison with the last meters of dynamic. From a safety point of view, depth diving is always done with a slight positive buoyancy. Negative buoyancy could cause problems in depth diving during the ascent, especially in a case of LOMC or BO.

Your next question is about kick rate. One important factor for the kick rate is the type of fins you use. For bi-fins a slow pace is usually used, while mono-fins are more effective at a high speed.

Also important is overall fitness, and kind of muscle development you have. In distance diving, oxygen metabolism and lactate production have a great influence on your speed. Going too slow could cause you to stop early due to lack of oxygen, going to fast could turn out in to a massive lactate build-up in your legs forcing you to terminate your dive.

The muscles consist of fast and slow fibers. To some extend the configuration in your body is dependant of your genetic make-up, however it is possible to train one or the other, changing the balance. This can be best seen in body builders and marathon runners. In diving, the first will likely be more prone to lactate build-up, the second more to oxygen lack. You should find out if this is an issue for you, and adapt both kick-rates as fin-type to your situation. I would suggest finding a buddy and trying different speed and distances to see what suits you best with your configuration, but perhaps other readers have better suggestions.

The third comment you made is that you wondered if your breathing pattern is right. It is difficult to change that over the internet and assistance from a fellow freediver with you locally or instructor is needed to find exactly out how right or wrong your breathing pattern is.

Next you wondered what a safe depth is with your numbers. Although there have been spoken about theoretical relationships between swimming pool distance and depth, I personally think it is very unwise to predict a depth on results in different disciplines. Although the metabolism rates and overall distance wouldn’t be much different, this theory doesn’t incorporate the needed adaptation to depth, like demonstrated in the phenomenon of blood shift. Even if you can do 200 meters dynamic, if you never have dived, you still could become in great trouble at 30 meters if your lungs aren’t adapted to the depth and pressure.

Finally some words about CO2 saturation. The time you need for getting rid of excess CO2 is dependant about the build-up during your dives. A tough dive would need a longer time, especially when there was build-up of lactate. For relative easy dives, a shorter interval can be used. This is something you will learn on experience, and is influenced by training.

I hope I didn’t disappoint you by don’t give you the numbers you requested, but I think it is the best next thing. Any comments?

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Rik: "In some individuals, depth fear could be replaced by wall-fear."
Hihi, I guess you mean me? LOL Yes I have a kind of fear for depth, but that's bottom fear. I'm afraight to hit the bottem whem I'm in the dark depth :D And with dynamics I've got some fear for hitting the wall deu to the speed an concentration on a good stroke.

As for your speed for dynamics, I think that around 70% of you maxium speed will do fine. Like Rik said it depends very much on your fins body and stroke. It takes experimentations to find a good rithm, stroke and posture.

Mine advise is:

- Find a freediving buddy,
- Do both a freedive course,

(these 2 are MOST important for your safety)

As you are now, please be very carefull!

- With a buddy you can rapidly improve your swimming style, speed, posture etc. As the other sees more points of improval.
Points like:
putting your arms over your head instead of allong,
keep one rithm, strech your legs ALL the time, look down or a little to the rear -4 fingers betwean head and chest-, etc.

I've trained with Rik, 8x 50m. And I clocked him, advised him one remark at the time. He was able to take 10 sec of his 50m time with NO extra effort. SO technique is VERY important.

For now that you're allone and want to train I say concentrate on stamina and technique. Do not hold your breath while practicing your stamina, you may go blackout and no-one would be allarmed! As it comes to technique, practice short distances only say 25m. I usually practice the shallow returnpoint, swimming only 2x 12,5m. My PR is 100m to put it in perspective.
As it comes to depth, only practice that with a experienced freedivebuddy! However you can practice the perfect duckdive in the pool! And that should safe you a great amout of energy outsite in the deep blue!

So find your buddy and take a course. It's so much nicer to have someone to share your findings with!

this is John, can't make the hockey game Friday as I will be going back to charlotte to pick some stuff up/take some stuff back home there.
Shoot me an email...we'll go get a beer.
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