Body Positioning/Trim Issues

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ADeadlierSnake

Contributor
Messages
150
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22
Location
Seattle, WA
# of dives
200 - 499
I have about 125 dives now, and for the last 60 or so, my trim has been pretty good. However I seem to have hit a standstill. I cant seem to make it feel "perfect" underwater. I believe my weight distribution is solid, so I am fairly certain that it is the body positioning that I cant seem to figure out. I see videos of people in proper trim, but everyone seems to do it slightly differently. So I found a drawing of a diver in trim, and I edited it twice to resemble 3 different poses that I commonly see in videos describing what good trim is supposed to look like.

scuba trim.jpgHere it is.

So which one of these is "proper trim"? One of them? All of them? I see A most frequently. However when I find myself in that position in the water, I cant do a good back kick. I also find that position to be highly unstable for me. Having my feet that far above my head makes me feel like I am upside down. No I do not get vertigo, but it just feels completely wrong in the water. And to do the aforementioned back kick, I have to drop my legs into position C. I cant seem to get enough power from position A.
Furthermore, I am having trouble dumping air from my drysuit. When my feet are above my head like that, almost all the air goes into my feet. When I go up even a few feet, it starts to pull something fierce, so I am forced to break trim completely and go vertical in the water in an attempt to vent my suit. While I do this, all the air rushes up to my shoulder area and makes me ascend a few feet. Eventually I get the air out and sink back down. However once I get back in trim, since the air is now more evenly distributed (a tiny bit in the chest/hands and a lot in the feet as opposed to all in the shoulders), I am now negative. Then I have to add some air to my wing to pick myself back up. I expend waaaaaaay too much effort in doing this little dance constantly every few feet. FYI I am only adding enough air in my suit to create loft. This is part of the reason I am having trouble getting air out of my suit (even with the valve all the way open). The air in my suit isnt creating enough pressure to escape the valve, even when all the air is in the shoulders. For this reason I am hesitant to take any weight off my rig, even though I think I can afford to be a couple pounds lighter.
It wasnt long ago that I would use my suit only for buoyancy control. Many people have told me not to do this. Yet I never had any issue with that. My buoyancy was a thousand times better doing it that way because I didnt have to do this f***ing dance every few feet. I had all the air in my suit, so it never had any trouble escaping the valve, meaning I could just turn to my side slightly and let a little trickle out.

In summary:

1. Which of those pictures, if any, represent proper trim?
2. Does anyone have any body positioning tips I can use...?
3. ...or a solution to my dumping issue?

Any help is appreciated

Dylan
 
B is closest to my view. Make your body looong, feet slightly above your head, when horizontal and moving forward. Body control is a part of buoyancy control. Body position changes during a dive depending upon task. Head down hovers are necessary to take some pictures, body angles change for different movement. Don't overthink this too much. (unless you are a demo model on a training video. My one tip- when just "cruising along," or pausing, make yourself long. When moving, do what needs to be done.
DivemasterDennis
 
A and B both show proper trim

A is standard for tech diving and better trim for anti-silting. I also use this trim for protection of the reef by keeping the feet as far from the bottom as possible.

B is acceptable trim for open water diving.

The feeling of being slightly head down takes some getting used to, but in time it becomes natural. You can check your "6 o'clock" by tilting your head down and looking back, and you don't shift your drysuit bubble that way.

Managment of the drysuit bubble also takes some practice, but eventually it, too, becomes routine. And you will find yourself using smaller and smaller amounts of air in the drysuit.

Sounds to me like you just need more time and practice.
 
A and B are both correct, and whether you use one or the other depends on how you need to position body parts to balance your equipment. C is suboptimal, because the knees are dropped.

One of the problems people often have with the back kick is pointing the tips of the fins UPWARDS. You see a little of this in A -- if the diver keeps the fin tips where they are to start the back kick, he will draw himself upwards and backwards. (It's called the "backward shrimp dance".) Of course, as he moves backwards and upwards, gas will fill his feet and expand, and he'll become unstable. The key to a good back kick is to start with a perfectly horizontal body, and fins that are horizontal, too.

It is normal, if you are horizontal with the knees bent, to have a little air in your feet. If you are finding yourself unstable in that position, you may have moved too much weight up on your body. But on ascent, for example, it is not uncommon to need to drop your feet briefly to move air. One of my instructors, Joe Talavera, said it drove him crazy to try to teach technical divers who were SO convinced they could never, ever break trim, that they would lose buoyancy control rather than drop their legs on ascent. Buoyancy trumps trim! And it's really only necessary to drop the feet briefly, or even go maybe 10 degrees feet down, to get the air out of the legs.

As far as your yo-yo problems go, this isn't a dry suit versus wing problem, it's a venting problem. It doesn't matter where you have the gas in your suit, so long as the right amount of gas is there to make you neutral. It may not be possible to hover perfectly still with the gas in the wrong place, but you won't lose buoyancy control just because the gas migrates to your shoulders. However, if you go out of trim to move gas and you KICK while you are doing it, you will drive yourself upwards in the water column, which will of course make you more buoyant until you vent.

If you are having to get vertical to vent your dry suit, one of a few things is true. Either your dump valve is in the wrong place, or it is not functioning well, or you have so little air in the suit that you have to get every last molecule out of it to stay neutral in the shallows. This is why I don't parse my weight that closely, and I dump the wing first as I come up. If you get all the air out of the wing first, the gas in the suit will have expanded to where it's easy to dump it. If that's not true, then you may be even slightly underweighted.

Having dived with you, I suspect all of these problems are much less dramatic than you make them sound, and that you are really obsessing about getting everything perfect (which is great; I love that in a dive buddy).
 
Part of it is obsession, especially with fundies in 13 days. However it is also accurate. I would love to go diving with you sometime in the next week to show you what I mean. I was diving with Dave and Samih today, and at one point during the dive, I went vertical, raised arm, etc just to see how it would dump. It seemed as if all the air that was in my feet just disappeared. I was completely vertical, valve open, and no air was coming out, despite the massive bubble I could feel in my feet. I had to just dump my wing at that point. Another thing of note is that generally I hover a few feet off the ground, and I am over 6' tall, so when I do go vertical, the gas will expand a bit, hence the lift in the shoulders. I am not kicking during this. Thats the last thing I would want to do.
The valve on my drysuit is in the wrong place though. This has been confirmed by numerous divers, including Mark at 5th D. And he says he used to be a Diving Concepts dealer, so I suspect he knows what he is talking about. I dont have time to change valve placement before fundies though. The dump valve may also need to be cleaned well. I am going to do that immediately upon waking up tomorrow. I would not be surprised if it is at least somewhat dirty. It has been about a week since I have properly washed my gear in the tub (ive been using C2 showers). I also keep very little air in the suit. I think.... Its a little hard to tell when every puff of air I put into it immediately goes into the feet. I am still slightly overweighted. I dropped 2 lbs of lead today, and I plan on dropping 2 more tomorrow. Part of me thinks this will help, because I will have less air in the suit to expand. The other part of me think it wont help, because like you said, its tough to get any out with minimal air in it. So I am not really sure what to do. One thing is for certain though. I dont enjoy being overweighted much.
Now.... back kick. I seem to only be able to perform a solid back kick while in position C. Or at least I think thats where I am... I have no video proof to back that up. I can only guess.

-------

Just something I am adding on to this post. I frequently see people in position C while out diving (Dave's trim is very much like that), and on youtube. For instance here: http://www.youtube.com/watch?feature=player_detailpage&v=H2O7ro67HZs#t=37s
This guys seems to have the arched back thing going on, and his feet are about level with his head. Same for the guy in this video: http://www.youtube.com/watch?feature=player_detailpage&v=HnJzOkUH7N4#t=54s
And I know I personally feel much more in control when I am trimmed like that.
 
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Part of it is obsession, especially with fundies in 13 days. However it is also accurate. I would love to go diving with you sometime in the next week to show you what I mean. I was diving with Dave and Samih today, and at one point during the dive, I went vertical, raised arm, etc just to see how it would dump. It seemed as if all the air that was in my feet just disappeared. I was completely vertical, valve open, and no air was coming out, despite the massive bubble I could feel in my feet. I had to just dump my wing at that point. Another thing of note is that generally I hover a few feet off the ground, and I am over 6' tall, so when I do go vertical, the gas will expand a bit, hence the lift in the shoulders. I am not kicking during this. Thats the last thing I would want to do.
The valve on my drysuit is in the wrong place though. This has been confirmed by numerous divers, including Mark at 5th D. And he says he used to be a Diving Concepts dealer, so I suspect he knows what he is talking about. I dont have time to change valve placement before fundies though. The dump valve may also need to be cleaned well. I am going to do that immediately upon waking up tomorrow. I would not be surprised if it is at least somewhat dirty. It has been about a week since I have properly washed my gear in the tub (ive been using C2 showers). I also keep very little air in the suit. I think.... Its a little hard to tell when every puff of air I put into it immediately goes into the feet. I am still slightly overweighted. I dropped 2 lbs of lead today, and I plan on dropping 2 more tomorrow. Part of me thinks this will help, because I will have less air in the suit to expand. The other part of me think it wont help, because like you said, its tough to get any out with minimal air in it. So I am not really sure what to do. One thing is for certain though. I dont enjoy being overweighted much.
Now.... back kick. I seem to only be able to perform a solid back kick while in position C. Or at least I think thats where I am... I have no video proof to back that up. I can only guess.

-------

Just something I am adding on to this post. I frequently see people in position C while out diving (Dave's trim is very much like that), and on youtube. For instance here: Frog Kick - YouTube
This guys seems to have the arched back thing going on, and his feet are about level with his head. Same for the guy in this video: DIR Modified Frog Kick - YouTube
And I know I personally feel much more in control when I am trimmed like that.

IMO if it feels good do it. You need to be comfortable while diving looking right isn't going to help. Comfort is the answer.
 
IMO if it feels good do it. You need to be comfortable while diving looking right isn't going to help. Comfort is the answer.

Yikes! Disregard that info.

Being in proper trim DOES NOT usually feel good at first. Mostly because in OW you were unfortunately taught to be more vertical than in trim. When you get into proper trim, with proper weighting, after practice it will become comfortable.

I suspect if you feel like you are upside down, you do NOT look like the diver in picture A. It's been my experience that people who feel like you describe have actually surpassed diver A and actually have their feet much higher. The best way I've found to resolve this is to have my students in my pool which has a 4' x 8' mirror in it. I have tried videoing the divers in bad trim, but they can't see it in real time. If they swim in front of a mirror, they can see what the issue is first hand, try to adjust while they are there, or come to the surface and move the tanks if need be.

Also, as far as air in the drysuit... How much air is in the suit? You should only have enough air in the suit to take the squeeze off. Your wing should be your primary method of bouyancy NOT your drysuit.
 
I was completely vertical, valve open, and no air was coming out, despite the massive bubble I could feel in my feet. I had to just dump my wing at that point

This confuses me. Surely you were not feeling a huge bubble in your feet when you were vertical and head up?

I think what you are saying is that you felt as though you had a lot of air in your feet, but when you went vertical to dump, no air came out of the suit, even though the bubble in the feet was gone. This actually isn't all that unusual -- if what you have is the right amount of air in the suit, but it's in the wrong place, you can move it around the suit without dumping it. This often happens to me in a cave -- I'll go head down to swim down a slope, and then have an uncomfortable amount of gas in my feet until I can find a place where I can drop them and get it to move up to my torso -- but I never actually dump any of it.

I also don't really understand your comment that you finally had to vent your wing. As I mentioned earlier, I vent my wing PREFERENTIALLY during an ascent, because the wing vents easier and faster than the suit. Once the bubble in the suit has expanded significantly, it is MUCH easier to vent the suit. If you cut your weight to the absolute dead minimum you can use, remember you have committed yourself to getting that wing AND suit absolutely empty to hold your shallow stop. That makes life difficult, because it often requires some contortions to get the suit that empty. In addition, it means you're sitting on deco with your suit shrinkwrapped, which is the last thing you want at the end of a dive, when you want your undergarment lofted and warm. In fact, now that I think of it, I wonder if your complaints about being cold, no matter what undergarment you use, may in part be due to running too LITTLE gas in your suit -- which will make venting it even harder.

The good news is that you have a class coming up in two weeks that will help you sort all of this out. USE Koos for what he's been taught to do, which is help you figure out how to use your equipment to make your diving easier and smoother. Too many people try to learn everything Fundies teaches before they ever get to the class, and they then pay top dollar for an in-water evaluation :) Koos is THERE to help you fix problems; let him do it.
 
Yikes! Disregard that info.

Being in proper trim DOES NOT usually feel good at first. Mostly because in OW you were unfortunately taught to be more vertical than in trim. When you get into proper trim, with proper weighting, after practice it will become comfortable.

I suspect if you feel like you are upside down, you do NOT look like the diver in picture A. It's been my experience that people who feel like you describe have actually surpassed diver A and actually have their feet much higher. The best way I've found to resolve this is to have my students in my pool which has a 4' x 8' mirror in it. I have tried videoing the divers in bad trim, but they can't see it in real time. If they swim in front of a mirror, they can see what the issue is first hand, try to adjust while they are there, or come to the surface and move the tanks if need be.

Also, as far as air in the drysuit... How much air is in the suit? You should only have enough air in the suit to take the squeeze off. Your wing should be your primary method of bouyancy NOT your drysuit.

Agree with you. However the OP has 125 dives. Just when does it stop ..."Being in proper trim DOES NOT usually feel good at first"? He past at first a while ago. In fact I find it rather strange with that many dives the op is asking such a question.
 
Superlyte27:
I suspect if you feel like you are upside down, you do NOT look like the diver in picture A. It's been my experience that people who feel like you describe have actually surpassed diver A and actually have their feet much higher. The best way I've found to resolve this is to have my students in my pool which has a 4' x 8' mirror in it. I have tried videoing the divers in bad trim, but they can't see it in real time. If they swim in front of a mirror, they can see what the issue is first hand, try to adjust while they are there, or come to the surface and move the tanks if need be.

Also, as far as air in the drysuit... How much air is in the suit? You should only have enough air in the suit to take the squeeze off. Your wing should be your primary method of bouyancy NOT your drysuit.

I have been trying to get someone to come out and video me. I think it should help me a lot, because right now, I am only going on feel. I could be wrong about where I am. But no matter how I feel underwater, everyone tells me my trim is "****ing awesome" or some variation of that.

Not much air is in it. The squeeze never really gets taken off though, because the air immediately rushes into the feet. My wing is my method of controlling buoyancy.


TSandM:
I think what you are saying is that you felt as though you had a lot of air in your feet, but when you went vertical to dump, no air came out of the suit, even though the bubble in the feet was gone. This actually isn't all that unusual -- if what you have is the right amount of air in the suit, but it's in the wrong place, you can move it around the suit without dumping it. This often happens to me in a cave -- I'll go head down to swim down a slope, and then have an uncomfortable amount of gas in my feet until I can find a place where I can drop them and get it to move up to my torso -- but I never actually dump any of it.

Yes, thats exactly what I was describing. However I can never move any air into my torso. Not when my feet are the highest point, which is apparently where they should be. This is why I prefer what I believe is Position C. I can actually get loft. Again, I gotta get some video first to be sure. If I get video, I will post it here.

TSandM:
In fact, now that I think of it, I wonder if your complaints about being cold, no matter what undergarment you use, may in part be due to running too LITTLE gas in your suit -- which will make venting it even harder.

Nada. Back then I was using 36 lbs of lead. Why? So that I COULD add air to my suit to stay warm. I just get cold easily. I was insanely overweighted then. I have not been experiencing the same cold now that the water temp has gone up a few degrees though. And im not even using Argon right now! I suspect I will need the new undergarment when winter comes back. I should be fine for summer though with the one I have. Thats a relief.


AfterDark:
Agree with you. However the OP has 125 dives. Just when does it stop ..."Being in proper trim DOES NOT usually feel good at first"? He past at first a while ago. In fact I find it rather strange with that many dives the op is asking such a question.

My trim is not bad. Not by any means. Part of the issue is that I did most of the first 60 dives in a wetsuit, all of the dives ~61 to ~110 using a drysuit as my main source of controlling buoyancy, and while wearing a standard back inflate BC (Scubapro knighthawk). I only very recently switched to a bp/w and thus switched to using that as my source of buoyancy control. So my kit has been getting a massive GUE-approved overhaul. As I told Superlyte, everyone sayd my trim is awesome, but I just dont FEEL like it is. Part of that is the dumping issue, which makes me feel less in control that I should be.
 
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