exertion after diving?

[jon m]

so what exactley is it? have you ever seen folks loading multiple tanks,gear,ect after dives? i'm talking 30- 40yds of sand , followed by (multiple) stairs just to get within 50yds of you vehicle... is this not post dive exertion? it SURELY exerted me!!!
is there a general rule of thumb regarding the possibility of getting bent because of post dive exertion? ie: wait 30min prior to exertion
just wondering... if waiting makes it safer then that's what i'll do- plus it gives me a reason to sit down and take a break!!!!!
-me

 

[DocVikingo]

Hi Jon M,

The following threads contain extensive and detailed discussons of this topic:

http://www.scubaboard.com/search.php?searchid=3924560

Happy reading.

Regards,

DocVikingo

 

[Rick Inman]

Or, if you want the bottom line, from 09/02/2004:

Hello medic diver:

Summary

As indicated above, this has been covered before. In a nutshell, I suggested that one wait about four hours between exercise and diving, and then one wait six hours between diving and post-dive exercise.

Rational

This is based on the idea that the lifetime for exercise-induced micronuclei is about one hour. The four hours should give sufficient time for these to resolve. Remember however, that nuclei will also be generated in the course of walking and lugging tanks, etc.

At the other end of the day, sixty minutes will allow for off gassing of the longest compartment generally encountered in recreational diving. If one is involved in deep diving (decompression required), the gas loads require longer times to be properly described. This six-hour recommendation will thus be too brief.

Dr Deco :doctor:

Readers, please note the next class in Decompression Physiology :1book:
http://wrigley.usc.edu/hyperbaric/advdeco.htm

 

[jon m]

link doesn't work-
thanks for the timeframe-
i guess my question is not so much about the formation of bubbles )not that i really understand that, just know it isn't good!), but what qualifies as excercise? are we talking going to the gym, or lugging tanks (as stated above)
if i wait 1hr before loading up the rig with gear, am i o-k? (generally speaking)
how are all ya'll doing it? thanks!
i searched "excersise after diving" and didn't get what iwas looking for.....
-me

 

[DandyDon]

DocV, your link doesn't work...??

link doesn't work-
thanks for the timeframe-
i guess my question is not so much about the formation of bubbles )not that i really understand that, just know it isn't good!), but what qualifies as excercise? are we talking going to the gym, or lugging tanks (as stated above)
if i wait 1hr before loading up the rig with gear, am i o-k? (generally speaking)
how are all ya'll doing it? thanks!
i searched "excersise after diving" and didn't get what iwas looking for.....
-me

While we're waiting on more info from professionals, here's an understanding from this non-pro anything...

DrD's quoted information is referencing more strenuous exercising, altho the gear humping you described in the first post would strike me as a consideration. In general...
>> I'd use DrD's guidelines for any gym type exercise;
>> If I had crowded the NDLs at all, I think I'd take that one hour break you suggested before humping the gear - using the time to hydrate more; and
>> On any deeper dive, I take an additional Safety Stop on the surface - the hidden stop - in which I do nothing but float for a minute or more. I certainly don't want to rush the ladder climbing exit with all that weight.

 

[Glitch]

I thought I'd add a bit more of confusion to this topic.
This topic was briefly covered at the Tech-Diving 2006 Seminar here in Stockholm www.tech-diving2006.org where Dr. Alf Brubakk gave a lecture on decompression theory. Recent studies actually indicate that moderate exercise prior and even after diving actually help off gasing rather than increasing the risk of bends.
Severe changes in temperature such as moving from a cold environment to a warm environment, i.e. a sauna , actually also appears to have a positive effect on off-gasing.
Dr. Brubakk has among many other experiments for example studie the effect on rats by rapidly heating them to 42 degrees C.
Another not very scientific but funny example he gave was that the finnish marine dives whom had a sauna on board of their vessels (which always was used after dives) have no reported cases of DCS.

There are also other relevant theories within this field. For example diving here in Sweden often means 2-4 degrees water temperatures at the bottom but in the shallows were most decompression takes place during the summer we can have up to 16-20 degrees C. This rapid temperature change is believed to have a very positive effect on off-gasing.

So basically what I am saying is that the old rule of strictly no exercise or hot showers/sauna .etc may actually be faulty princples as recent studies within the field indicate the opposite.

/C

 

[DandyDon]

All that would depend on how you read & view it, Glitch - as I am sure that moderate excercise and positive temperature changes would encourage off gassing - but I don't want to do that. I want to off gas slowly - not rapidly.

You might complete the dive info on your profile to add depth to your posts, btw.

 

[HowardE]

Here's a thread about excercise and diving

http://www.scubaboard.com/showthread.php?t=119989

 

[Dr Deco]

Hello jon m:

Exercise

By “exercise,” we mean any musculoskeletal activity. Thus, running and hauling dive gear would fall into this category.

Many people think of exercise as it would be performed in gym. However, in the case of the Dr Deco forum, I mean it as used by a physiologist. The body does not really know if you are lifting weights in a gym or on board a boat.

Exercise at Depth

By this is meant strenuous activity that increases blood flow to muscles and connective tissue. This would include such activities as strong finning at depth, e.g., to swim against a current. These activities accelerate the uptake of nitrogen to the tissues and increase the “dose’ of nitrogen above what was intended by the calculator of the decompression table.

All tables that are tested included exercise at pressure. This is naturally to load the tissues in a manner consistent with work underwater as would be performed by a commercial diver. This is an old technique and nothing discovered recently.

When divers are warm underwater and cold during decompression [or on the surface], DCS can result. This was found to occur with the US Navy salvage divers recovering TWA flight 800 in Long Island Sound. The effect is attributed to blood flow changes.

Exercise During Decompression

Mild activity during decompression helps to increase the blood flow. If it is mild, the perfusion increase will take precedence over micronuclei formation.

Exercise is also employed in Air Force and NASA decompression procedures. it is very successful if the activity is not too intense.

For several years on this FORUM, I have advised readers to move a bit during the decompression (surfacing) portion of the dive. This would include finning while at the safety stop and movement while on the boat. I have also suggested that sleeping during the surface intervals is not good, since it reduces blood flow to the lowest level.


Dr Deco :doctor:

 

[Dive-aholic]

Jon, I have that issue after most of my dives in Florida. There, we can leave our gear unattended for a few minutes at the water without much worry of theft. I don't know how that works where you dive.

What we always do is once we surface from our dive, we hang out at the surface for at least 10 minutes. This is spring diving so we don't have any surf to be concerned with. I'm not sure how you can deal with this issue. Standing near the water isn't really good because you're still exerting yourself by having your gear on.

Once our 10 minutes is up we slowly ascend the stairs with just the gear we are wearing and make our way to the van. We take off our tanks and unzip our suits. After a few minutes we'll start collecting the rest of our tanks (deco and stage). We carry one tank back at a time.

We know a diver that did that on a regular basis and then one day he blew off his surface time and carried all of his gear back to the truck at once. A couple hours later he was riding the chamber. The only thing he did differently on this dive from most of his others was the post dive routine.

Hope this helps.