(6/28/2005) Like your exercise? Ever been bent? Read this

[Nobby]

Unlucky Mate

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Originally Posted by Tim Ingersoll
Just returned from Cozumel. Seven day trip staying at the Presidente with wife and kids. Got bent.
Took the first day off from diving and did the family thing. Started the day with a workout at the resort gym. Did the same workout I do here at home. Twenty minutes of cardio and then 40 minutes with the weights. Had a few drinks that night. Nothing out of control. Drank water before turning in. Drank plenty of liquids the next morning. Dove with Aldora as usual. Drank a pint of water on the ride out. First dive Palancar Gardens. Max depth: 105 feet. Most of the dive spent between 60 and 80 feet. Duration 70+ minutes. Interval was almost two hours. Drank a pint of water at the interval and another on the boat out. Second dive was max depth of approximately 80 feet for 70+ minutes. Most of the dive spent at or above 60 feet. I dive with two computers a Suunto Fusion and an Oceanic Veo 200. The Oceanic never had a problem with my profile the first day. The Suunto called for a five minute deco stop at fifteen feet. It cleared in less than three minutes. I stayed at the safety stop for a total of seven minutes.
That night I had approximately four alcoholic drinks. Once again, two glasses of water before bed, Juice and water with breakfast. Two cups of coffee. Water on the boat ride out. First dive was Colmbia Normale. Once again max depth approximately 105 feet. Duration a little over an hour. Most of the dive was spent between 60 and 80 feet. Water at the surface interval of approximately 2 hours. Second dive was max depth of 80 feet. Most of the dive was between 50 and 60 feet. Duration was over an hour. My Oceanic said no problem. The Suunto called for a three minute stop at 15 feet. I stayed five minutes.
Upon returning to the boat my left shoulder immediately started to hurt. Dull ache consistent with a muscle sprain. I blew it off as just that (Nobody gets bent after four dives right?). The pain subsided somewhat but was still notceable for the remainder of the day. I self-medicated somewhat with alcohol (yeah, yeah, I know). I posted a thread under the "Ask Dr. Decompression" category and received responses later that day basically telling me not to be stupid and get it checked out. The most effective post was "Denial is the last step before recovery." I still didn't want to believe I got bent. I woke up at 2 in the morning and believed it. The pain was worse.

Tim

This is a good report. I can empathise with you. I too got bent in Cozumel; a mixture of cowboy DM antics and probably, and more to the point the drinking that I did before and after the dive. I learned a valuable lesson and now don't even have a snifter whilst diving. I learned the hard way, but as Neitsche said ' What doesn't kill you makes you stronger'. I qualify the following statement from research as a PADI instructor and a bachelors degree in Sport Science and Sports Physiology.

I would like to point out a couple of things that could have also contributed to your DCS. Firstly, and well documented, exercise before and after diving. This should be avoided. When you exercise the body warms up and the blood pressure naturally rises to transport more oxygen rich blood around the body. You put your muscles and tissues under further pressure by increased load and exertion. Imagine what is happening inside your body, it can be equated to ascending too quickly. The tissues that have absorbed nitrogen are under pressure at depth are, if you ascend slowly slowly decreasing the pressure on the tissues, off gasing all the time. If we ascend too fast (change in pressure gradients) the nitrogen may leave the tissues and enter into the bloodstream as bubbles. It is of course when these bubbles travelling in our bloodstream get caught in the joints or worse still get into the heart that the situation may be serious.

As you read one may say I know all this so why is he telling me. The tissues and the surrounding blood vessels at sea level are at 1 ATM, as we exercise our body warms and the tissues are put under pressure (upto 100 times more than that of a 30m/100ft dive) Light aerobic activities, like walking and swimming, mildly increase heart rate and redirect blood from organs to muscle and associated tissues. Before a dive, such exercise will not affect nitrogen uptake. After a dive, it would be expected to promote safe off-gassing and inhibit bubble formation and expansion. In fact, some studies suggest light exercise decreases the incidence of DCS.

However, vigorous aerobic exercise, like hard running or strenuous hiking, produces pronounced changes. Markedly increased temperature, blood flow, and oxygen use within tissues immediately before a dive could result in an undesirably rapid uptake of nitrogen upon descent. After a dive, such exercise or an exhausting surface swim to the boat could contribute to a dangerously accelerated elimination rate.

DAN’s Medical Centre website suggests a two-hour delay after exercise as a minimum guideline for diving and considers four hours safer. Since vigorous postdive exercise almost surely is more pernicious than pre-dive activity, additional conservatism seems warranted. Some studies suggest that while the biggest increase in risk may occur within an hour or two of arduous exercise just before and just after a dive, risk likely remains somewhat elevated up to six hours.
Of course, the number and frequency of dives on any trip will bear on the degree of conservatism that would be prudent. For example, after 3-4 days of diving deep walls, you’ll want to be more cautious than when doing only a single shallow dive and then returning home.
Dehydration and exerciseinduced pain are exercise-related factors that can prove problematic. Risk statistics consistently show a sizeable association between dehydration and susceptibility to DCS. Perspiration due to vigorous exercise, especially in hot weather, can further the fluid loss already inherent in scuba. Given that joint pain is among the most common symptoms of DCS, injuries to joints and muscles provide fertile ground for confusion between DCS-related pain and exercise-induced discomfort. Avoid them, and the unnecessary chamber visits they may occasion.

The best advice is moderation. Stay well hydrated and warm. Avoid strenuous exercise of any type for 4 and 6 hours before and after diving, respectively, but remain mildly active between dives and for a while after the last dive. Reduce anxiety and confusion about symptoms of DCS by knowing the location and characteristics of your pre-dive aches and pains, and be alert to changes in their nature or intensity.

IF IN DOUBT AND AS A MATTER OF COURSE DITCH THE PRIDE AND GUZZLE SOME OXYGEN. IT WON'T HURT IF YOU DON'T HAVE DCS BUT IT WILL HELP IF YOU DO.

 

[Kriterian]

I don't understand where the suprise comes from in the title "Unlucky Mate". You didn't mention decompression so I'm assuming you only did that 3 minute safety stop each time, you also didn't mention the gas so I'm assuming air.

First dive = Max 105 ft (avg 70 ft) for 70+ minutes?! The NDL for 70 ft is only 35 minutes and if you go by your deepest point (which you should) your NDL is only 12 minutes.

Two hour SI.

Second dive = 80 ft for 70 minutes. With the surface interval, your NDL would be 15 minutes. You would have been down almost 3 times as long as the NDL if this was the first dive, but it wasn't...

Overnight SI, with alcohol.

First dive = 105 ft for 60 minutes? I'm not sure what's going on or what's left out of the story but you should have been bent way before now.

Two hour SI.

Second dive = 80 ft for another 60 minutes.

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What am I missing exactly that makes you think this is because of the alcohol + exercise instead of the dives themselves?

 

[Scot M]

He said that he was diving within both of his computers' limits. That suggests that his profiles weren't too outrageous.

 

[Nobby]

I don't understand where the suprise comes from in the title "Unlucky Mate". You didn't mention decompression so I'm assuming you only did that 3 minute safety stop each time, you also didn't mention the gas so I'm assuming air.

First dive = Max 105 ft (avg 70 ft) for 70+ minutes?! The NDL for 70 ft is only 35 minutes and if you go by your deepest point (which you should) your NDL is only 12 minutes.

Two hour SI.

Second dive = 80 ft for 70 minutes. With the surface interval, your NDL would be 15 minutes. You would have been down almost 3 times as long as the NDL if this was the first dive, but it wasn't...

Overnight SI, with alcohol.

First dive = 105 ft for 60 minutes? I'm not sure what's going on or what's left out of the story but you should have been bent way before now.

Two hour SI.

Second dive = 80 ft for another 60 minutes.

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What am I missing exactly that makes you think this is because of the alcohol + exercise instead of the dives themselves?

Kriterian

Firstly, this wasn't me! Secondly I didn't get my tables out to check out his story, but didn't need too as he was diving on his computers (admittedly his computers could have been wrong) but both of them? The oceanic which using more conservative Logarithm didn't alarm (odd cos the Suunto did) he did the deco and more at 15 ft he mentions this in his script! His drinking wasn't excessive either.

I don't think that you read the post properly? Otherwise you will have noticed that he had two computers and that he did his deco and that my post is purely informative and does not directly suggest that it was only the exercise that caused Tim's DCS. Further to this Tim presumably dived with someone else on these dives. By your deductions his buddy should have been bent too then?!

 

[Nobby]

He said that he was diving within both of his computers' limits. That suggests that his profiles weren't too outrageous.

cheers

 

[Kriterian]

Kriterian

Firstly, this wasn't me! Secondly I didn't get my tables out to check out his story, but didn't need too as he was diving on his computers (admittedly his computers could have been wrong) but both of them? The oceanic which using more conservative Logarithm didn't alarm (odd cos the Suunto did) he did the deco and more at 15 ft he mentions this in his script! His drinking wasn't excessive either.

Sorry, I didn't meant to say you and by the time I noticed there was far too many instances to go back and correct.

I don't think that you read the post properly? Otherwise you will have noticed that he had two computers and that he did his deco and that my post is purely informative and does not directly suggest that it was only the exercise that caused Tim's DCS. Further to this Tim presumably dived with someone else on these dives. By your deductions his buddy should have been bent too then?!

I understood the part about him following the computers, that's why I was asking what I was missing from the story. A gas other than air? Decompression that wasn't mentioned? The conclusion about the exercise + alchohol was gained from the red section that was quoted, not the original story. Also the title of the thread made it sound like you were warning every one off of diving + exercise.

Again, I'd like to reiterate that I'm not placing blame or saying you (or Tim) said or did anything wrong. I'm just trying to figure out what I'm doing wrong in MY calculations. Looking at a normal NDL (not a deco one) table makes these dives look bad.

 

[Tom725]

If one of the computers was into deco then you were pushing the limits, particularly for multiple dives on consecutive days. Add in the exercise and alchol and you are further testing fate (the computer does not know how much you drank or exercised.)

You are never guaranteed you will not get bent, even if you dive within your computer and even within the tables. We all puch limits sometimes and sometimes the limits bite back.

 

[Nobby]

Sorry, I didn't meant to say you and by the time I noticed there was far too many instances to go back and correct.



I understood the part about him following the computers, that's why I was asking what I was missing from the story. A gas other than air? Decompression that wasn't mentioned? The conclusion about the exercise + alchohol was gained from the red section that was quoted, not the original story. Also the title of the thread made it sound like you were warning every one off of diving + exercise.

Again, I'd like to reiterate that I'm not placing blame or saying you (or Tim) said or did anything wrong. I'm just trying to figure out what I'm doing wrong in MY calculations. Looking at a normal NDL (not a deco one) table makes these dives look bad.

Roger, understood.

I WAS highlighting the effects of exercise and diving though. If anyone is interested there are several well documented journals that have highlighted the dangers of exercise combined with dving. The risks based on physiological models are real. And just because we can never pin DCS on anything in-particular as there are so many parameters to consider...age, health, air mix, water temperature, post dive activity etc etc we should be more aware of the considerations when aiming to reduce the factors....Exercise is one of them.

 

[Doc]

I WAS highlighting the effects of exercise and diving though. If anyone is interested there are several well documented journals that have highlighted the dangers of exercise combined with dving. The risks based on physiological models are real. .

Not exactly anything new.

"Whenever I feel the urge to exercise, I lie down until the feeling subsides"
W.C. Fields

 

[cornfed]

Again, I'd like to reiterate that I'm not placing blame or saying you (or Tim) said or did anything wrong. I'm just trying to figure out what I'm doing wrong in MY calculations. Looking at a normal NDL (not a deco one) table makes these dives look bad.

For one of the dives he said he his max depth was 105' and the dive lasted 70 minutes. He also said most of his dive was spent between 60 and 80 feet. If you assume his average depth was 70 feet you'll see that the profile wasn't all that agressive (compared with spending all 70 minutes at at 105 feet).