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Fin vs. no-fin = +25% ???

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Hi Goran, just a question for Branko, about the bi-fin - mono-fin ratio, how far can you get using bi-fins?

honestly I do not know my maximum yet in any discipline :-/ because idea of samba is out of question for me at the moment. but I did some experimental training mostly with static, I tryed to by doing static increase other disciplines, but also now I am starting with practicing dinamic, no fins, no limit ;-) results are just amaseing! but untill get result I want, I would like to listen, more than talk :)

in my humble opinion in next few years you will have dinamic 400+, no llimit 300+, static 15min+
 
honestly I do not know my maximum yet in any discipline :-/ because idea of samba is out of question for me at the moment. but I did some experimental training mostly with static, I tried to by doing static increase other disciplines, but also now I am starting with practising dynamic, no fins, no limit ;-) results are just amazing! but until get result I want, I would like to listen, more than talk :)

in my humble opinion in next few years you will have dynamic 400+, no limit 300+, static 15min+

In the Next few years?

It's hard to believe for me.
But then again I'm of the time when the WR dynamic was still 187 something upon when Peter Pedersen did the incredible 200!

Well maybe after you did your WR static next year in a competition you may want to try for a nice dynamic bi-fins to say 200+? - come up easy as a preview for what's next ;)

But I haven't heard of people comparing their dynamic monofin to their Bi-fin numbers. I must admit that I haven't tried a max dynamic in a while, and it was even longer that I did it BI-fins. I think my BI-fin pb is 110m done in 2003 I think. pb with mono is 150m. Seems like I need to give it a go soon :)
 
There is also one factor what you have to consider with dnf and that is the strong puss off from the wall. The puss off with a mono creates rather a lot of drag and many dont push at al because its bad for the mono. So with every turning point you gain a lot "free" meters by forcefully pushing from the wall. So if you place a person with mono and a person with no fin in an ocean an they must swim in one straight line, you problebe will get a much more distance differences. Since the person with no fin have no wall anymore to make the extra meters by every turn.
 
There is also one factor what you have to consider with dnf and that is the strong puss off from the wall. The puss off with a mono creates rather a lot of drag and many dont push at al because its bad for the mono. So with every turning point you gain a lot "free" meters by forcefully pushing from the wall. So if you place a person with mono and a person with no fin in an ocean an they must swim in one straight line, you problebe will get a much more distance differences. Since the person with no fin have no wall anymore to make the extra meters by every turn.

I'm not so sure about the difference changing much is diving without pool walls.
I've seen Dave mullins doing 250+ in a 25m pool. I don't think he'll do much more in a 50m pool.

My PB DNF is from a 50m pool. - but then again one cannot draw conclusions from a few individual performances. We need people like Ivo Truxca to do the number crunching. :hmm
 
I'm not doubting your abilities Dave, really.
But I doubt the difference in energy use monofinning in a 25m vs a 50m when you got a smooth turn and a push versus skipping a turn.

Though I must say a 50m is much nicer, because you don't have those lousy turns all the time, and You have to endure some. Maybe I just think this because I'm just weird having a pb dynamic - with mono, in a 25m pool, and having a DNF pb in a 50m pool :D LOL

I hope you'll find the ability to show Goran who's boss this year :) Oh and don't rule out those other hounds in the race! - I think it's very nice it's an exiting neck a neck race :)
 
My perfs don't really say anything about the 25m vs 50m debate though, do they?
 
Hi kars, i think you misunderstood my reply. I replyed at the question why the difference is so small between dyn+fin and dnf.
When i do dnf, i kinda feels like i'm cheating because of the powrrfull push from the wall. I gain (for example) 5m gliding where i otherwise with armstroke wil glide for 2m. So its feels like that every time i turn, i cheat 3m of gliding and O2 conservation.
I have the feeling if i have swim in an swimmingpool of 500m, i will reach less distance because i will have make more armstrokes use more O2. And there will be no extra relaxing glides after every turn.
Maybe i'm totaly wrong, i'm kinda new here.
But this is how it feels like to me. In a 25m pool you can push-glide more than in a 50m.
 
We already had a similar discussion about 25m vs 50m pools before the WC in Lignano, where the DNF was untraditionally in a 50m pool. Almost everyone feared great performance degradation (some spoke about an average loss of up to 30%). Having some experience, and having already processed a lot of data, I was confident it wouldn't be the case, and that the loss would be negligible if any at all. Guess who was right.

I wrote an article showing the statistical results, and even comparing DNF on WC 2009 (25m) and WC 2011 (50m). You can have a look at it at APNEA.cz - Blog I am attaching the first chart from the report here below, but there are some more in the article. This chart shows 29 personal records (there were also 3 national records), and the average increase of 6% to previous PB. The increase would be little bit less if we took only the top athletes, but definitely we would be very far from some performance degradation of tens of percents, predicted by some.

DNF_WC11xPB_a.gif


So frankly told, I agree that in open water the difference between DNF and DYN might be slightly higher, but doubt it would make for more difference than just very few percents. There is a loss of O2, energy, time, and momentum at DNF at every turn anyway, so taking away the turns surprisingly does not impact the performance as much as people use to think.
 
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Interesting :) it does make sence that you conserve energy without al that turning. Wish that some scientist put some sensors on mullins or other top divers and measure theire musle tensions while diving. So we kan see how much tension we use when we turn in the pool. Ofcourse it also can be my lack of technique of turning ;-)
 
It also depends on the amount of mass the diver has. More mass more benefit.

Just ditch your neck weight, exhale to be neutral, and do a 50m dive, compare speed, strokes, length of glide, length of push of wall glide.

But indeed the topic started off as a comparison of with and without fins. Since it's distance is relative close, are the dive times of dnf and dyn also close?
For me it is.
 
For me 50m DYN with monofin it's much better not for the time but for the concetration. Turns usually takes more energy but if you get used to them it get easier and more efficient.
I'm training in a 25M pool and when i'm swithcing in the summer to the 50m pool it's hard at the beggining to get used to the distance without the turns but after 1-2 days it's getting better.
I think it's personal what an athlete can do in a 25/50m pool.
 
Hi again. Great discussion guys. The question seems easely answered, but it is surprisingly complex too me. Sometimes it's just really confusing.

Just to get a better overview personally, I'd like to list some things covered in this thread so far:


DYN longer than DNF:


- Roughly speeking, the ratio is pretty much established as a trend: from 18% (Mullins vs. Gorans record dives) to a mean of 36% from thousands of results (Trux), but with possibly bigger differences in the individual diver, some PB smaller, but mostly bigger differences. Some dives 100% longer with fins...

- An exact trend-percentage is impossible to establish.



Some relevant/possible factors involved:


- The fin is driven by a body totally unsuited for the purpose. All the joints positions, muscle connections etc are wrong.

- The pace at which a mono really comes into its own is well above the optimum for freediving.

- Additional drag of the monofin (or bifins),

- Possibility to gain more from push-off at DNF,

- More natural and relaxing movements at DNF,

- The lower velocity (and hence lower drag force) at DNF,

- You use more muscle groups at DNF. Once the vasonstriction kicks in, they work practically without taking away any oxygen needed the core. They can generate more power without using oxygen. So the more muscles you use, the more power is available for the propulsion.



Arguments against a (much) longer DYN dive in open water, relative to DNF:


- The ratio Fin/No-Fin is only slightly bigger in vertical records (1,23) than in horisontal (1,18). Vertical dives might indicate what a no-wall/pool-dive would be like. But other factors aply to vertical dives also.

- Distances covered in 25m and 50m pools are not that different in DNF as people in general thougt it would be before the world championships in Italy (as described by Trux). Because the "loss of push-off" is balanced with a "gain from continued inertia." The same migt aply to DYN. (BUT this seems to be a key issue, because it might not be the case, that things are balanced).




Arguments for a (much) longer DYN dive in open water, relative to DNF:


- The monofin works better above a certain minimum speed. Speed wich is lost in turns.

- The monofin gives a slightly higher speed, so lost inertia in turns is slightly higher.

- A barefeet push-off is probably a relatively effective movement, if you look at "distance gained vs. O2 used", since the wall is rock-steady.
And therefore the monofin-turn is probably less effective, because it's less easy too benefit from the wall.

- Turning a big monofin is more energi costfull.

- Turning with monofin might be more mentally costfull/stressful than barefeet: Lost inertia, lost rythm etc. and therefore more O2 costfull (might not be the case though).


----------------------------------------------------


My money, for now, goes on the horse that argues, that there is something to gain for fins in a dive in open water (wich most can agree on). And that the gain is more than "just a little", or "a few percent" (not really clear).

But on the other hand, in a larger perspective, I also agree that the difference in open water DYN/DNF would not be "huge" (not clear)... It would probably be a 10 -20 -30 % gain, not 60 - 80 -100 % gain... That is with the existing fins and methods. Things migth change...

But it's a bit confusing still... And these are just thoughts, reallity might look different... :)

------------------------------------------------------

What would be nice to have now, is if Trux could make a statistic between DYN in 25m and 50m pools (and even 15m), to estimate what effect the turns have when wearing (mono)fins.

The problem is, that even if people started to ad data, most people are used to the 50m pool, so the data would be biased in favour of the 50m pool dive I think.
 
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