Strenous Exercise after Diving: How Long Should I Wait?

[pasley]

I have read the information on hiking after diving, but in Southern California, there really is not much choice. Most of our dive sites are at the base of a 50-160 foot cliff. Sometimes there are stairs or a paved ramp (Laguna) but usually just a goat trail, or worse. I too am not young anymore, as I will be 51 in just 3 months.

I don’t push the NDL limits. I do dive a AL80 tank, so how far could I push it? On dives below 60 feet, I start my ascent when I hit 8 or 9 minutes of bottom time remaining. As I slowly work my way up, the balance between using up bottom time and the decreased depth increasing my bottom time usually work out to me only loosing a minute of bottom time, and then getting it back. I do try to surface a bit off shore, and just relax as I slowly fin my way in the last 100 yards or so. So I should have about 20 to 30 minutes after I came up from depth (and at least 3 minutes at 15 feet), before I hit the beach. If the hill is a particularly bad climb (flat rock or Christmas tree), I will grab a rock for a bit and rest before tackling the hill. But, it is an increased risk, no way around it.

Now back to the original point. IMHO, going diving for a tank or two, would make a nice substitute for the day he spends on the stair climber in terms of exercise, while observing the good doctors advice to limit your pre and post dive exercise.

 

[headhunter]

The following is from the article linked in post#3 above:

Vigorous aerobic exercise, like hard running or strenuous hiking, can produce pronounced changes in body temperature, blood flow, and oxygen use within tissues. Done immediately before a dive, this could result in an undesirably rapid uptake of nitrogen upon descent. After a dive, such exercise could contribute to a dangerously accelerated elimination rate and/or the formation of micronuclei.

Some scuba venues, like Hawaii, invite arduous post-dive hiking to altitudes that can seriously compound the worries. Don’t hike too soon after diving, and if trekking remotely near altitudes of 8,000 feet, follow DAN flying-after-diving recommendations of waiting 12 or more hours after making a single no-decompression dive and 17 or more hours after making repetitive dives.

Best regards.

DocVikingo

The diving I'm referring to is the California diving that Pasley talks about, where we really don't have a choice. I'm not talking about diving in the morning and then going out for a little hike up a volcano in the afternoon. That is what the Hawaiian scuba venues sound like that you mention.

The article helps me to understand the risks. I was just trying to come up with some "rules of thumb" that would help lessen the risks without having to sit at the base of a cliff for 6 hours before returning to my car at the top of the cliff.

For instance, it sounds like waiting for a half hour to an hour would greatly reduce the risk as compared to coming out of the water and only pausing to remove my fins while hiking up the hill back to my car in my full gear.

Thanks Doc!

Christian

 

[Dr Deco]

Hello headhunter:

Post dive Exercise

One must always remember that exercise and stable bubble formation are gas-load dependent. If one must make ascents up a steep hill, and you do not have a Sherpa for the day, then it is necessary to avoid big tissue nitrogen loads if you wish to avoid DCS.

Clearly, no one develops DCS in a gym from lifting weights. It is a combination of tissue supersaturation and exercise that are the culprits. Thus, if you perform a dive that remains at some distance from big tissue loads and you wait a while before the climb, you will be in a better position to avoid decompression problems post dive.

Exact Science?

It is surprising in a controlled, laboratory situation, just how exact decompression is. The problem of decompression not being an exact science is that recreational divers cannot easily ascertain their individual variations with respect to deco. Therefore it appears to be a “crap shoot” on every dive. :11:

Dr Deco :doctor:

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

 

[headhunter]

Thus, if you perform a dive that remains at some distance from big tissue loads and you wait a while before the climb, you will be in a better position to avoid decompression problems post dive.

So, if I understand this statement correctly, one of the things that I should strive to do on a dive where I need to make a strenuous hike back to the car is to leave somewhat of a large "buffer" between the dive that I do and the NDLs. The closer to the NDLs I come, the more time I should give myself after the dive to increase this "buffer".

If this is correct, is there a corrolation between the group designation letters in the Navy tables (for example) and "post dive" physical activity. In other words, should you be in a certain "group" or better before going up the hill after a dive?

Also, if an individual is regularly going out on 10 - 15 mile hikes with a 60 pound backback (not pre or post dive), does this produce a positive effect when that same person makes a short 200 yard hike up a hill to get back to his car?

My thought is that with the "extra conditioning" one would have from regularly hiking with a heavy pack, a short hike up a hill with 75 - 100 pounds of gear would seem relatively easy. Am I correct in thinking that if you have conditioned yourself to do a much more strenuous activity (yet similar activity) that this post dive hike would become less of a liability?

Thanks for your answers.

Christian

 

[Dr Deco]

Hi christian:

Physical conditioning is a very big plus when it comes to off gassing. This has been shown in recent laboratory tests.

The other point is essentially “does physical conditioning prevent nuclei formation.” That has not yet been studied and is related to stress-assisted nucleiation. I would not guess that there is a direct relationship as there is with dissolved nitrogen elimination.

Dr Deco :doctor:

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

 

[mccabejc]

I suppose one way to improve upon the beach diving conundrum might be to spread a big blanket on the beach, drop your gear there after the first dive (cover it to protect from sand) and do your SI under an umbrella while vegetating and drinking Gatorade. That way you bypass lugging your gear up the hill and down again.

Or, if you're only doing one dive, just hang out for an hour or so under the umbrella and then lug your stuff back to the car later, maybe making a couple trips (weights on one trip, then tank on another) so you are minimizing the exertion. Of course that doubles the uphill climbs...

 

[Uncle Pug]

there really is not much choice.

we really don't have a choice.

There is always a choice. You are just chosing to ignore that fact so you can make a poor choice seem to be the only choice. That is not only unwise it is also unfortunate since there is more than one good choice.

 

[headhunter]

There is always a choice. You are just chosing to ignore that fact so you can make a poor choice seem to be the only choice. That is not only unwise it is also unfortunate since there is more than one good choice.

Hey there Uncle Pug!

I appreciate your input and respect your experience.

I agree that with anything we do in life there is always a choice even if that choice is not to do something.

In this case, I think that when I used the phrase "the California diving that Pasley talks about, where we really don't have a choice", I probably should have completed that thought by saying, "...we really don't have a choice once we make the decision to dive that location as we usually would". I recognize that this is one extreme end of a spectrum of choices. It could be considered a poor choice if it raises the risk to a level that either ignores safety standards or is simply unnecessary to being able to dive in that location (whatever location that might be).

Here is the other extreme of a spectrum of choices. We could simply make the choice not to dive any of the California locations that require a high level of physical exertion to access or get back to our vehicle from. That is the safest choice, albeit one that simply limits our choice of great locations available to us for diving.

I agree that you are probably correct in saying that "there is more than one good choice". I think the fact that Pasley and I have posted questions in this discussion, shows that we are looking for "better" choices than those that we are currently aware of. I, for one, am not trying to make it seem like a poor or unsafe choice is the only one. I am a safety conscious individual.

Many of these locations are accessed by climbing down a "goat path" from the edge of a 200 to 300 foot cliff to the waters edge. Others require walking down a steep road or path for an eighth to a quarter of a mile.

That brings us to the question at hand. What would be a "better" and "safer" way of conducting these dives?

I'm looking for ways to change our procedures so that we could raise our safety levels at these locations.

Thanks for any suggestions that you could share with us.

Christian

 

[Saturation]

Exertion in and about diving is part of technical diving, its done all the time. Aside from being fit to reduce the issues regarding circulation and optimize offgassing, execute the dive extra conservatively and pay special attention to prolonging safety stops, degearing, and resting after the dive. For example, without an option to prolong deco for extra conservatism, consider using nitrox, dive air tables, shorten bottom times. At dives' end, lugging gear up a hill should be done at least 1 hour after the dive, more delay the better, and the load should be broken up to make each trek as light as possible. Find the least difficult route there, and use any worksavers possible: carts, wheel barrows etc.

Dr. D has published papers about the effects of lower leg movements on nuclei generation, so even the climb alone is a problem, so delay such work as long as possible.

The exertion up/down a hill and lifting is less taxing for a fit person. However, we do not know what the relationship is between fitness, motion and nuclei generation, but we have some information on motion alone as a nuclei generation source.

Purely hypothetically consider that in muscle physiology, muscle fibers gain strength via growing larger, not multiplying in number. When a stronger person lifts a weight, he uses less muscle fibers, thus the chances of nuclei generation maybe less. For increasing strength needs, muscle fibers are recruited to the lift, more being used for greater strength, and more chances for nucleation. However, a fit person who rushes, moves quickly, has to recruit more muscles than performing the same task slowly and languidly.

Finally, these types of peri-dive exertions have been done for some time without much issue, particularly in cave diving and in locales like San Diego, CA. If one disobeys these rules, you are not guaranteed to be in harms way. These added rules reduce the risk of issues further in a sport that is fundamentally safe, so implement them as best you can. Only in rare active divers who have had an unexpected hits where no cause can be found do such rules become more imperative.

 

[headhunter]

Many thanks to DocVikingo, Dr. Deco and Saturation for the outstanding information that they make available to all of us on ScubaBoard.

I think that you have all put things in proper perspective and given us some information that will allow us to add a few "rules of thumb" to our pre and post diving activity that may increase our level of safety.

We are all very fortunate to have so many knowledgeable people on the board that can help us make better choices through the increased availability of information.

My regards to all of you.

Christian