Over exertion

[InTheDrink]

I love the fitness discussion in this thread, and agree divers should maintain a level of fitness appropriate to our sport. Sadly, there is a problem with some DM's who "travel" a lot during a dive. They dive the route almost daily, are familiar with the sites and terrain, and sometimes forget that their followers are not in the same circumstances. Divers see and want to observe things, and lag behind if the DM is inattentive. The divers , being on a guided dive, are likely less active and proficient than the DM. Separation from the group can lead a diver to not only heavy exertion, but also stress. I think divers who find they are being rushed or pulled along too fast should say so to the DM after the dive and before another one. Nearly all ( but unfortunately not all) will respond appropriately. And if you are a DM reading this thread, take note. I hear a lot of folks complain about DM's who move too much and too fast. Talk to you divers, let brief the dive accurately including factor of movement and pace, and get their input and expectations. Modify your plan accordingly. And divers, speak up, please. If you are paying $100 or more for a 2 tank excursion, you are entitled to reasonable consideration. Its a recreational dive. It's suppose to be fun. For everyone.
DivemasterDennis

You're gonna LOVE this. One of my instructors on my last course wore split fins. He's a pretty hard core deep CCR diver and not one that I'd thought would be a split fin man. I asked him about it. His reason: simple - it's to slow him down so he's not too fast for his students (bearing in mind his students will all have several hundred dives). I thnks that's quite a noble and responsible position to take. And also neatly puts the splits/paddle debate to bed once and for all

Interestingly, he's also a big man and could probably do with a few less sauaage and bacon sarnies. But he is fit, or those muscles at least are fit, and there's nearly nothing he couldn't deal with in terms of stress (I know this as he saved my life).

I'm not saying fitness is everything, but it is a component and a significant one.

Composure, relaxation and fitness are all aspects that should be taken into consideration.

The other thing DivemasterDennis, is that I know for a fact some DMs purposefully rip through the dive so their guests burn through their gas quickly and can get the dive over with. Not saying it's the norm but it certainly does happen.

John

 

[nimoh]

You're gonna LOVE this. One of my instructors on my last course wore split fins. He's a pretty hard core deep CCR diver and not one that I'd thought would be a split fin man. I asked him about it. His reason: simple - it's to slow him down so he's not too fast for his students (bearing in mind his students will all have several hundred dives). I thnks that's quite a noble and responsible position to take. And also neatly puts the splits/paddle debate to bed once and for all

Interestingly, he's also a big man and could probably do with a few less sauaage and bacon sarnies. But he is fit, or those muscles at least are fit, and there's nearly nothing he couldn't deal with in terms of stress (I know this as he saved my life).

I'm not saying fitness is everything, but it is a component and a significant one.

Composure, relaxation and fitness are all aspects that should be taken into consideration.

The other thing DivemasterDennis, is that I know for a fact some DMs purposefully rip through the dive so their guests burn through their gas quickly and can get the dive over with. Not saying it's the norm but it certainly does happen.

John

Even though I personally don't like split fins, I don't see how one person's experience "puts the splits/paddle debate to bed once and for all" -- there are a lot of people that prefer split fins.

 

[Hatul]

My thinking is that a lot has to do with different viscosity of water vs air. In water we need to make out motions much slower, and I think that's the source of much anxiety. We're used to moving through air, which offers little resistance to movement, and when we get into water we tend to panic when we can't make the same rapid motion. If there's a problem underwater it's usually best to slow down or stop. Same goes for getting stuck on kelp. Just slow down and the kelp slips by, and if not stop and move the kelp away.

 

[bpotkin]

I personally see a high value being in good cardio condition. In sports when you get tired the first sign of it shows up in your thinking.

 

[Kevrumbo]

ingentaconnect Fatal Respiratory Failure During a Technical Rebreather Dive at E...

Abstract:
Mitchell SJ, Cronjé FJ, Meintjes WAJ, Britz HC. Fatal respiratory failure during a “technical” rebreather dive at extreme pressure. Aviat Space Environ Med 2007; 78:81-86. A diving fatality at the extreme depth of 264 m fresh water is described. The diver was equipped with an underwater video camera which recorded events leading to his death. These events corroborated predictions about respiratory complications at extreme pressure made by early researchers. Review of the video and relevant literature resulted in the following physiological interpretation: an increase in respired gas density during descent caused a progressive increase in resistance to flow in both the airways and the breathing circuit. Initially, this was associated with a shift to ventilation at higher lung volumes, a relative degree of hypoventilation, and mild permissive hypercapnia. The promotion of turbulent airway flow by increasing gas density resulted in effort-independent expiratory flow at lower flow rates than usual. The consequent inability to match ventilation to the demands of physical work at the bottom precipitated a spiraling crisis of dyspnea, increasing PaCO₂, and wasted respiratory effort, thus producing more CO₂. Extreme hypercapnia eventually led to unconsciousness. This tragic case provides a timely and salient lesson to a growing population of deep “technical” divers that there are physiological limitations that must be understood and considered when planning extreme dives.

See also David Shaw (diver), Bushman's Hole South Africa.

 

[Bob DBF]

My thinking is that a lot has to do with different viscosity of water vs air. In water we need to make out motions much slower, and I think that's the source of much anxiety. We're used to moving through air, which offers little resistance to movement, and when we get into water we tend to panic when we can't make the same rapid motion. If there's a problem underwater it's usually best to slow down or stop. Same goes for getting stuck on kelp. Just slow down and the kelp slips by, and if not stop and move the kelp away.

My part B to this is to selectivly push yourself, in benign situations, and find out what your limits are. When you get that voice to say "screw this" and start focusing on survival instead of whatever task (following a fast DM) you wanted to accomplish, you will be a lot safer. Knowing you are headed into an incident cycle will help you break it, regardless of how fit you are.




Bob
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I may be old, but I’m not dead yet.

 

[InTheDrink]

Even though I personally don't like split fins, I don't see how one person's experience "puts the splits/paddle debate to bed once and for all" -- there are a lot of people that prefer split fins.

It was a joke.

 

[nimoh]

It was a joke.

sorry about that, looking back, I guess I missed the ""

 

[socaljohn]

I had been working out regularly for yrs, started missing days so I started skipping the elliptical and just lifting. Then after a shore dive to a local treasure we call Deadmans reef (almost a 1/4 mile swim) I realized I needed the aerobic so now I skip the weights and spend most of an hour on the elliptical. If I ever get back to everyday though, I will get some lifting in.

 

[Bob DBF]

Originally Posted by InTheDrink

It was a joke.

sorry about that, looking back, I guess I missed the ""

And I thought I'd never have to see a Split vrs Paddle thread again. D**n #$%@!!!!



Bob
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I may be old, but I’m not dead yet.