Orientation during deco/safety stop

[dumpsterDiver]

So is the recommendation of continuous light exercise (bicycling) now commonly accepted as the appropriate procedure to be performed during deco?

Based on what I have observed, it seems that many divers seem to strive to be motionless during deco rather than performing exercises.

Exercise versus being suspended motionless would seem to have a larger physiological impact than simply body position?

 

[Dr Deco]

Hello dumpster Diver:

I do not believe that currently there is a generally agreed upon activity during decompression .

Dr Deco :doctor:

The next class in Decompression Physiology for 2006 is September 16 – 17. :1book: http://wrigley.usc.edu/hyperbaric/advdeco.htm

 

[DrSteve]

Hello dumpster Diver:

I do not believe that currently there is a generally agreed upon activity during decompression .

Dr Deco :doctor:

The next class in Decompression Physiology for 2006 is September 16 – 17. :1book: http://wrigley.usc.edu/hyperbaric/advdeco.htm

But Dr Deco...wouldn't it make conceptual sense to do some mild movement? Afterall the average wet suit/dry suit/boots etc., are rather snug (if they fit properly) and could reduce circulation to the extremities like the feet and thus reduce off gassing. I am thinking that a lot of people on SB worry about a bent toe or finger...few people worry about a major hit and if they do, aren't asking about it on SB.

 

[Kevrumbo]

(From GUE's Fundamentals of Technical Diving, Ch.10 Decompression Sickness, p.93):

Light exercise during decompression seems likely to increase blood flow, possibly increasing offgassng efficiency. Evidence for this assertion was discovered in altitude decompression trials where subjects either rested or exercised during oxygen breathing prior to decompression to 30,000 feet. During this testing, 10 of 16 resting trials resulted in DCI while zero of 10 exercising trials resulted in DCI. Futrher indications that light exercise may be beneficial came in the early 80's as divers performing light exercise for 60 minutes at depth showed a roughly 30 percent decrease in decompression time (D. Vann 1982a)

 

[Saturation]

Dr. D mentioned early on on the benefits of light exercise in offgassing and it can be found around SB archives. More recently this has emerged:

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16118578&query_hl=1&itool=pubmed_docsum

However, is it a standard practice? I don't think so. However, you've not much to loose if you follow what 'light' exercise means, and that's to the equivalent of <= 4 Mets.

 

[rookers]

Making sure you don't have and spots where the circulation is constricted seems a good idea. Stretching out and moving things around a bit is probably also a good idea. We practiced this a bit at stops in my deco class and I carry on the practice.

 

[Dr Deco]

Hello Kevrumbo:

That is most interesting to see the quote from the GUE book. It has taken considerable work to get this idea accepted.

Curiously, the quote is date “1982.” This is long before the aspect of exercise was ever known. Prior to 1989, all evidence of exercise and DCS was unfavorable with respect to activity and DCS. Additionally, the researchers in this area were not Dr Vann but rater Pilmanis and Webb (US Air Force) and me (NASA).

Dr Deco :doctor:

The next class in Decompression Physiology for 2006 is September 16 – 17. :1book: http://wrigley.usc.edu/hyperbaric/advdeco.htm

 

[Saturation]

Here are older discussions:

http://www.scubaboard.com/showthread.php?p=482667&highlight=exercise+deco#post482667

http://www.scubaboard.com/showthread.php?p=758767&highlight=exercise+deco#post758767

http://www.scubaboard.com/showthread.php?p=482667&highlight=diving+exercise#post482667

 

[Beppe]

If you are vertical and lose buoyancy upwards you need to flip through more than 90 degrees to be able to kick down.

No need to flip and kick,just exhale.

 

[dumpsterDiver]

I have been doing light exercise on deco for a while and I think I remember reading on the "internet" years ago that DIR divers didn't even like to be holding tightly to a rope or equipment on deco because it may affect circulation in the hand and forearm.

I recently had a friend who took a mild elbow hit from what we think was caused by him keeping his elbow flexed and motionless to faciltate hanging spearguns over his arm on deco.

When he came up and complained about the hit, I asked him if the arm that hurt was the one that he hung his guns from and he ended up being kinda pissed that I never told him to avoid this practice. He now does both a deep stop and will keep his arms and legs loose during deco.

I try to work my elbows and shoulders a little during deco and also kick a little too.

Again, this issue seems a lot more important than body position.....