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Dive distance/effort simulation

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Well-Known Member
Jan 21, 2003
I don't get to the ocean regularly, and have been trying to simulate what a dive will require while still in the pool.
Simulation of clearing and compression seems pretty easy. Full exhale and reverse pack, then clear to the bottom of a 4 m pool should be equal to more than 50 meters. How to mimic the distance and effort pattern of a dive is less clear. Here is what I have been doing.

45 meter dive: surface dive and kick 20 meters, glide and/or hang for 25 seconds (1 m/s free fall), kick 45 meters.

Has anyone tried anything like this? Clearing and psychological issues aside, does this realy mimic a 40 m dive? How might I modify it to come closer to what a real dive will require.


One of the very best diver/teachers uses something very similar. Sounds realistic to me. Maybe go harder on the first 20 to simulate getting off the surface.
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Bill (and his master) are right,
I use something similar but with a swimming table, I use it with the flat line in front of me to give me more resistance. After the first 20 meters I let it go.
since i don't have a pool i do dynamics in the bay here at 10-12m. i count kicks instead of measuring meters, so maybe there are some deviations.
interestingly i find the actual dive easier. even with the same warm-up and breath-up the dynamic seems more demanding than the dive. 25 sec of contractions during the dynamic are a lot harder than the 25 sec of contractions on a 45m dive.
somehow my 'simulation' translates to roughly a 1:45 dynamic being as hard as a 2:00 cw.


I can't quite visualize a swimming table. Could you give a little more detail


Language problems

Hi Connor,
It was a language mistake, I meant a kickboard


  • kick-board.jpg
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Thanks to all for your help.

This is a very interesting technique, I've workd up to a 50 meter dive simulation. Can't wait to get to the ocean, next week if the hurricanes will get out of the way.

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This technique is exactly what I need and have been looking for to augment pool sessons, Conner. Thanks for sharing it.

When you get back in deep water, let me know how the pool simulation compares with real depth.

My limited experience is that the pool simulation is actually harder than the equivalent depth. I imagine this is to do with the pressure induced adaptations you get in the ocean that you don’t get or aren’t as strong in the pool.

Most of my training is pool based so I’d expect that all other things being equal my pool performances would out do my ocean performances but it is not the case.

My numbers:
Constant weight PB 52m – did not really push very hard on this dive. I dive fast with a mono – dive time 1:25 (27s to 35m, 18s glide to 52m, 40s back to the surface)

Pool simulation would therefore be:
35m dynamic, 18s hang static, 52m dynamic.

I wouldn’t get anywhere near that in the pool given that my best dynamic ever is 90m and that was really pushing it.

Even though I don’t get much opportunity to dive deep in the ocean it seems a lot easier than the pool….to me anyway.
Maybe having Bill with me for the ocean dive was what made the difference!!

Connor – I think that 50m simulation you are doing will have you in a great position to hit the targets you are after – good luck and dive safe with a reliable buddy!

I think Frank's got the right idea. The biggest difference kicking wise is on a constant the resistance changes throughout the dive. Most resistance being the start of the dive, and kicking off the bottom. I thought about using a bucket with a rope, or could atach to a weightbelt. If you just grabbed onto the rope then can drop it at the end. So something like swim 25m(with bucket), static, swim 25m, let go of bucket and swim last 25m. A bucket may be too much drag through the water, unless perhaps using a small one. I also thought about plastic drinking cups atached to a weighbelt. I have seen swimmers use a belt with a sponge hanging off for resistance.

I think the times on a constant will be a lot longer then dynamic, specially on deeper dives. My PB dynamic is 150m in about 1.35, my PB constant is 80m in about 2.45, both with monofin. On my dynamic I use full swimmers streamlining so is quicker then how I kick on my constant. That aside I think the difference in speed is the glide phase(slow) but also the added resistance of bouyancy changes. So swimming so many m on a dynamic may not be a good simulation of swimming the equivalent in m of a constant.

But then if you add the resistance I think most people would do less distance in the dynamic simulation then an actual constant dive. Like Andy said you do get a much stronger dive reflex on a constant dive so that does reduce O2 consumption. ie when kicking up from the bottom you have a lot of vasocontriction and bradycardia. You will get much less blood flowing to the legs so at that stage they tend to work much more anaerobically. Gives you that nice burn on the ascent ;)
So if you added the resistance you may have to reduce the distance for the simulation..... Doh !
Although training wise would be better and closer to the real thing, it's not as nice to work out what you might be able to do on a constant compared to the simulation. :duh

Just thought of something. Even with a normal simulation you want to take off 5-10m of your final swim. On a constant you don't kick the last 5m or so, just float up. Perhaps do another 5-10 seconds static at the end ?
I don't know how you would simulate the decreased resistance at the end. Perhaps very light kicking ?

The Walter´s idea of drag is something I also think about, and I believe the best way to simulate the end low resistance is to release the drag.

I´ve found this training more useful if you make on exhalation, of course should change the distances.
It might be awhile before I get to deep water again, but the replies to this thread are very interesting and make sense to me. I bow to the more experiened and will gratefully take these thoughts to the pool this winter. My initial instinct is supportive of pool work distances being more difficult than equivalent CB depths in open water. My PB is only 102' in a 4mm suit so far and I seldom get the chance to go for depth. I spearfish mostly. I can do 50 meters dynamic with or without fins fairly easily when I've been practicing awhile and my 102' was not too much of a push so I'm not really a reliable judge at this point.
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