exertion after diving?

[Kendall Raine]

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:

Using post dive Doppler after helium based dives involving an hour or more of decompression (dives to 250 on 15/55 TMX), my friends and I have found:

1. Riding scooters at depth significantly reduces post dive bubble scores.
2. Light movement during deco hangs reduces post dive bubble scores.
3. Getting out of the rig in the water and winching the rig on the boat reduces post dive bubble scores.
4. Cold water dives increase scores.
5. Lack of sleep and hydration increase scores.

We have not enough comparative data on the effect of pre-dive excercise (1 hour on tread mill previous day) to say if this, too, reduces scores as suggested by several studies as well as field work by WKPP.

We look at the 30 minutes post dive as peak venous bubble point with most of us pretty clean after 60 minutes post dive. We avoid lifting gear, when possible, during this window.

Waddling across the beach and up the stairs after a beach dive is a pain but usually follows such minor exposures that we haven't had any problems. Waiting past the window would be better. Having your children meet you at the water line and carry your gear up for you is best.

 

[Dive-aholic]

Having your children meet you at the water line and carry your gear up for you is best.

I like that idea! Too bad I don't have any kids. :frown: On 2nd though, it's not that bad.

Does anyone have any kids they'd like to rent out everyone couple of weeks. Must be able to carry doubles.

 

[DandyDon]

I like that idea! Too bad I don't have any kids. :frown: On 2nd though, it's not that bad.

Does anyone have any kids they'd like to rent out everyone couple of weeks. Must be able to carry doubles.

A well trained mule would be a lot cheaper, easier to manage, etc.

 

[Dive-aholic]

A well trained mule would be a lot cheaper, easier to manage, etc.

True, as stubborn as they can be, they might listen better! Especially is you feed them treats!

 

[Kendall Raine]

True, as stubborn as they can be, they might listen better! Especially is you feed them treats!

Sure. Mule. Great. Only problem is you need to get it in and out of the car, feed it, clean up after it and keep people from trying to ride it while you're doing your dive. We're talking a beach dive, here, not an expedition to the Pit.

 

[DandyDon]

Sure. Mule. Great. Only problem is you need to get it in and out of the car, feed it, clean up after it and keep people from trying to ride it while you're doing your dive. We're talking a beach dive, here, not an expedition to the Pit.

Yeah, still sounds easier than raising kids. Maybe a scuba valet would be cheaper?

"Here, kid - hold my keys & cell phone."

 

[Dr Deco]

Hello Readers:

The posting from Kendall Raine is fascinating. I might have expected the cold water dives to have a lower Doppler score unless there was considerable activity to maintain body warmth.

It is always interesting to get feedback from divers in the field.

Dr Deco :doctor:

 

[dumpsterDiver]

Maybe I could spend the day diving hard and then ask my wife to load the gear into the truck and then drag it out, wash it and hang it to dry while I'm "decompressing" in a hot tub? I'm sure the resulting tissue damage (from just asking her to do this) would far exceed anything a few billion tiny bubbles could do to me.

 

[WesTexDiver]

Maybe I could spend the day diving hard and then ask my wife to load the gear into the truck and then drag it out, wash it and hang it to dry while I'm "decompressing" in a hot tub? I'm sure the resulting tissue damage (from just asking her to do this) would far exceed anything a few billion tiny bubbles could do to me.

I almost spilled my coffee reading this!