freediving weight

[Hank49]

My weighting varies. If I'm wearing a lot of wetsuit (3.5 mil full with a 2 mil hooded vest) I use 8-10 lbs. This makes me neutral around 15-20 feet.
In the warmer months, like now, I wear just the vest and a long sleeve shirt. I still use 6 lbs of weight, which is more negative than 8-10 with the full suit. Don't know why, but I feel more comfortable dropping down with little neoprene. And I can stay longer with less effort.
Safety is first. My buddy and I do one up, one down as much as possible. Sometimes we get separated if one got a fish and went back to the boat.

 

[redstrom]

I was taught (by IANTD as well as PFI) to put on enough weight so that you are neutrally buoyant at 33ft, whether wearing a 14mm or being butt naked.

The rationale being that something like 95%(?) of all black-outs occur in the final 33ft on ascent or right after a diver has surfaced. Hence, by weighting at 33ft you cover most of you bases, and you should float to the surface if experiencing a black-out.

Safety comes with knowing you own limits. More importanly, ALWAYS dive with a spotter on the surface (or one that will meet you at depth for deeper dives).

Hey guys,
I am going to start freediving this summer in fresh water. To start out I will just be in my swim suit, no wetsuit. I am was wondering how much weight I would need. I am 5'10 195lbs. Any input would be appreciated. Thanks

 

[Hank49]

I was taught (by IANTD as well as PFI) to put on enough weight so that you are neutrally buoyant at 33ft, whether wearing a 14mm or being butt naked.

The rationale being that something like 95%(?) of all black-outs occur in the final 33ft on ascent or right after a diver has surfaced. Hence, by weighting at 33ft you cover most of you bases, and you should float to the surface if experiencing a black-out.

Safety comes with knowing you own limits. More importanly, ALWAYS dive with a spotter on the surface (or one that will meet you at depth for deeper dives).

I don't totally agree with this concept. In theory, yes but in reality it doesn't work.
You're saying you should be neutral at around 30 feet so you'll float if you blackout nearer the surface. But that's neutral with your lungs full. If you black out, you'll exhale....and most likely sink.
To be neutral at even 15 feet after exhaling, you'd need floats, or little to no weight.
As you said, the only real safe way is having a good buddy.

 

[cmburch]

I weight to be neutral at about my working depth. I am neutral at 30 feet and work 30-40 feet.

Using a 7mm Farmer John wetsuit, if weighted for 33 feet and hunting 10-20 feet it will be very hard to stay at less than 12 feet.

I carry some more weight on my board if I see something at shallower depths.

 

[Akimbo]

so your saying that your less likely to black out when your a new freediver?
are you saying that because if you are new you are less likely to push the limit?

Not quite. New freedivers have not developed the ability to cope with the natural urge to breathe induced by elevated CO2, or learn to be as relaxed as experienced freedivers. It is difficult to burn enough Oxygen in a lung full of air to reach hypoxic levels without first reaching such high CO2 levels that untrained people experience severe distress or panic. Drowning from panic is not the same as SWB.

The first medical observation of this learned response (basically ignoring elevated CO2 symptoms) that I became aware of was by physiologists working with the US Navy UDT (Underwater Demolition Teams/Frogmen) after WWII. SWB that we know today was a relatively rare incident with the UDT since their objective was to swim long distances at shallow depths, thus the PPO2 effect was not so pronounced. Also, these subjects were in particularly excellent physical condition with above average cardio-pulmonary functions. Actual samples of exhalations were taken and compared between trainees and team members and the disparity was noted. The conclusion as I recall was that an increased CO2 tolerance was observed but no theory was offered to explain the phenomenon. My unsupported presumption was these guys just toughed their way though it like all the other discomforts of their career.

Considering that the phenomenon has relatively recently been observed and understood with anything resembling a significant frequency, it is reasonable to conclude that it has not been a problem for the thousands of years people have practiced casual diving apnea. The advent of advanced apnea techniques, long bladed fins, good thermal protection, and apnea diving becoming a competitive sport is when SWB has become common enough to observe, analyze, and accurately diagnose.

…i have taken a Performance Freediving class and no where in that class do they say you don't have to worry about blackouts when you are new to the sport. that happens to be the main thing you need to be worryed about!...

That is not what I wrote.

… Although it is usually not an issue with beginning freedivers, SWB (Shallow Water Blackout) is about the only physiological issue you should be aware of. ...

The operative word is usually. The point was that SWB (used as shorthand for all the flavors of hypoxia) is something that freedivers should become aware of. I felt it was appropriate to mention SWB during my first post, but not be an alarmist. Incorrect weight management is a far greater risk to new freedivers than SWB and is the question at hand.

 

[Akimbo]

I don't totally agree with this concept. In theory, yes but in reality it doesn't work.
You're saying you should be neutral at around 30 feet so you'll float if you blackout nearer the surface. But that's neutral with your lungs full. If you black out, you'll exhale....and most likely sink.
To be neutral at even 15 feet after exhaling, you'd need floats, or little to no weight.
As you said, the only real safe way is having a good buddy.

We may be discussing a more advanced condition set than was first asked. I am afraid our answers to mbalmr's questions may be too far off in the weeds and maybe unnecessarily technical. It has been my experience that new freedivers have a lot of trouble reaching 30' let alone staying there long enough to enjoy themselves. Considering the circumstance of a new freediver, how do these recommendations sound?

1. Never adjust your buoyancy so you are negative at the surface when freediving. You want to be buoyant enough that you can float totally relaxed in preparation for your dive. This is because it is less work, more enjoyable, and will improve lung and tissue gas levels.

2. If you are naturally negative or want an added safety margin, add buoyancy in the form of a wetsuit. It is desirable to wear a wetsuit with sufficient excess buoyancy that you will float to the surface from your maximum depth after dropping a weight belt.

3. Do not forget lung and suit compression in your estimates.

4. Ideally, you will be neutrally buoyant when you reach your intended depth and do not have to expend excessive energy to reach depth. This may be a compromise of neutral at 30-40' for experienced freedivers who might go much deeper. It can also be neutral at 10' if that is the bottom.

5. It is always good practice to trade off freediving and observing as rescue diver with a buddy — as opposed to diving together. This is to guard against any form of blackout.

6. Don’t hyperventilate more than three deep breaths before diving and don’t push your limits because it could cause you to blackout near or even after surfacing.

7. It is advisable to investigate Shallow Water Blackout (the most Google'able phrase) if you go beyond casual snorkeling or are intellectually curious.

8. Have a lot of fun.

 

[redstrom]

That's a good summary - Akimbo.

The "neutral at 33ft recommendation" was meant for freedivers operating down to 100ft. The target or max depth in my beginner class was 33ft, and in my intermediate class 100ft. In both cases we were taught to be neutral at 33ft, for the reasons stated in my earlier post.

...and as someone pointed out... if diving shallower than 33ft you obviously need to be neutral at less depth.

A point here though, being overly buoyant doesn't necessarily mean that you are a safer diver. Being too buoyant will make you struggle to decend, burn more energy/oxygen, and limit how deep you can go or time spent at depth. As stated above, the only one that can save you if you blackout is your spotter who should be monitoring your dive.

 

[madprops]

Not quite. New freedivers have not developed the ability to cope with the natural urge to breathe induced by elevated CO2, or learn to be as relaxed as experienced freedivers. It is difficult to burn enough Oxygen in a lung full of air to reach hypoxic levels without first reaching such high CO2 levels that untrained people experience severe distress or panic. Drowning from panic is not the same as SWB.

The first medical observation of this learned response (basically ignoring elevated CO2 symptoms) that I became aware of was by physiologists working with the US Navy UDT (Underwater Demolition Teams/Frogmen) after WWII. SWB that we know today was a relatively rare incident with the UDT since their objective was to swim long distances at shallow depths, thus the PPO2 effect was not so pronounced. Also, these subjects were in particularly excellent physical condition with above average cardio-pulmonary functions. Actual samples of exhalations were taken and compared between trainees and team members and the disparity was noted. The conclusion as I recall was that an increased CO2 tolerance was observed but no theory was offered to explain the phenomenon. My unsupported presumption was these guys just toughed their way though it like all the other discomforts of their career.

Considering that the phenomenon has relatively recently been observed and understood with anything resembling a significant frequency, it is reasonable to conclude that it has not been a problem for the thousands of years people have practiced casual diving apnea. The advent of advanced apnea techniques, long bladed fins, good thermal protection, and apnea diving becoming a competitive sport is when SWB has become common enough to observe, analyze, and accurately diagnose.



That is not what I wrote.



The operative word is usually. The point was that SWB (used as shorthand for all the flavors of hypoxia) is something that freedivers should become aware of. I felt it was appropriate to mention SWB during my first post, but not be an alarmist. Incorrect weight management is a far greater risk to new freedivers than SWB and is the question at hand.

i just don't agree with how you said it in your first post that is all. you seem to know what your talking about.

but new freedivers trying new ways to breathe up try hyperventilation. when you do that it makes it really easy to not breathe. no warning signs go off and you can black out fast with out getting the need to breathe. that is how a new freediver can black out.

i see you talked a bit about it in your last post.
all i would ask is that you do not say new freedivers don't have to worry about blacking out. that is just not true. some one might read that and nothing else and it could end bad

 

[Akimbo]

i just don't agree with how you said it in your first post that is all. you seem to know what your talking about.

but new freedivers trying new ways to breathe up try hyperventilation. when you do that it makes it really easy to not breathe. no warning signs go off and you can black out fast with out getting the need to breathe. that is how a new freediver can black out.

i see you talked a bit about it in your last post.
all i would ask is that you do not say new freedivers don't have to worry about blacking out. that is just not true. some one might read that and nothing else and it could end bad

I just don’t understand. I never said "new freedivers don't have to worry about blacking out." If you read my post it says that blackout is what they should be aware of:

… Although it is usually not an issue with beginning freedivers, SWB (Shallow Water Blackout) is about the only physiological issue you should be aware of. This link is worth looking over.

Welcome to DiveWise - the Freediving Education Initiative...

The link provides a thorough and understandable overview of all forms of freediving hypoxia. It is true that hypoxia rarely affects new freedivers, and I think we agree that it is something they should be aware of. I believe that is what I wrote.

I don’t think it is appropriate to inundate everyone buying a mask and snorkel with warning labels, pages of technical reading, or require a C-card for a problem that is so rare among new freedivers it has only recently been identified. Drowning from improper weighting is another matter.

Perhaps concerned forum members should develop a simple and concise overview for freedivers that we can link to. It could be made a sticky thread in the freediving forum if it is well written enough.