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View Full Version : Difference of the dolphin kick in Breast



ehoch
October 22nd, 2008, 03:07 PM
PURPOSE:To assess the effect of adding a dolphin kick to a breaststroke pullout.
METHODS:Eleven (20.9±2.3 yrs, 1.86±0.05 m, 79.6±5.5 kg) swimmers experienced with performing traditional and dolphin kick breaststroke pullouts participated in the study. Underwater video analysis was used to track whole body center of mass kinematics during a pullout. Time for the center of mass to travel distances ranging from 2.5-4 m from the initiation of the pullout were computed. Hand force data were derived from differential pressure measurements during the pulling phase of the pullout.
RESULTS:Use of a dolphin kick in a breaststroke pullout significantly (p=0.016) improved performance. Time for the center of mass to travel 4m after the initiation of the pull was reduced by 0.19 s. This performance improvement was not attributable to enhanced force production from the pull. Hand force was not significantly different between pullout techniques for the right hand (p=0.142) nor left hand (p=0.303). Total impulse produced by the pull was reduced by 3.6% (p=0.039, ES=0.34) when using the dolphin kick pullout.
CONCLUSIONS:These data suggest that the use of a dolphin kick during a breaststroke pullout provides a significant advantage over the traditional no-dolphin kick pullout. Furthermore, this advantage comes from enhanced propulsion from the kick but not the pull.

Glider
October 22nd, 2008, 03:12 PM
eh - this is good info for this breaststroker. What's the information source?

Dang it though, my ankle inflexibility makes this somewhat limiting for me. My ankles make my feet nothing but two big old boat anchors.


PURPOSE:To assess the effect of adding a dolphin kick to a breaststroke pullout.
METHODS:Eleven (20.9±2.3 yrs, 1.86±0.05 m, 79.6±5.5 kg) swimmers experienced with performing traditional and dolphin kick breaststroke pullouts participated in the study. Underwater video analysis was used to track whole body center of mass kinematics during a pullout. Time for the center of mass to travel distances ranging from 2.5-4 m from the initiation of the pullout were computed. Hand force data were derived from differential pressure measurements during the pulling phase of the pullout.
RESULTS:Use of a dolphin kick in a breaststroke pullout significantly (p=0.016) improved performance. Time for the center of mass to travel 4m after the initiation of the pull was reduced by 0.19 s. This performance improvement was not attributable to enhanced force production from the pull. Hand force was not significantly different between pullout techniques for the right hand (p=0.142) nor left hand (p=0.303). Total impulse produced by the pull was reduced by 3.6% (p=0.039, ES=0.34) when using the dolphin kick pullout.
CONCLUSIONS:These data suggest that the use of a dolphin kick during a breaststroke pullout provides a significant advantage over the traditional no-dolphin kick pullout. Furthermore, this advantage comes from enhanced propulsion from the kick but not the pull.

daveindc
October 22nd, 2008, 03:28 PM
Is this legal? I have never even heard of doing this.

quicksilver
October 22nd, 2008, 03:42 PM
Is this legal? I have never even heard of doing this.


You're allowed to take 1 dolphin kick either before or after your pullout.

knelson
October 22nd, 2008, 03:46 PM
I'd be more interested in time differences, a 50/100/200 breast with and without the dolphin kicks. I have no idea what the results referenced mean.

It seems to me an average of 0.19 seconds per pullout. Pretty significant when you get out to a short course 200 breast. That would be 1.5 seconds.

ehoch
October 22nd, 2008, 04:17 PM
Here is the source - they often come up with all kinds of interesting stuff. There is another one on the thumb position: ACSM 55th Annual Meeting Indianapolis, Presentation Number, 2110.

Just to clarify and translate -

Time for the center of mass to travel distances ranging from 2.5-4 m from the initiation of the pullout were computed

This is for a single pull-out and the analysis starts from the initiation of the pull-out (not starting from the wall - and no, they did not study Kitajima's pullout)


if I expend extra energy for a dolphin kick every 25/50 it will cost me somewhere else.
Even if it were 1.5 seconds over the course of a 200, for me that is about a .5% to 1% improvement. I'd rather spend the time I could spend on this to learn better effeciencies elsewhere in my stroke. Time spent learning a more efficient dive could probably give as much or more improvement, and could be transferrable to other strokes.

That makes no sense - are you really trying to tell me that you are not doing a single dolphin kick on your breaststroke pull-out ?

TheGoodSmith
October 22nd, 2008, 04:21 PM
It's faster.

That's why it used to be called "cheating".


John Smith

knelson
October 22nd, 2008, 05:07 PM
If I'm reading the excerpt correctly, it references a range of 2.5 to 4 m. I'd rather see that range increased to a full event distance.

That wouldn't work. They need to isolate the effect of the dolphin kick. If they measured an entire race it would be too difficult to exclude other effects.

Anything allowed in the rules is, by definition, not cheating. You don't see many people still touching the wall on their backs in backstroke turns, do you?

stillwater
October 22nd, 2008, 05:13 PM
Correct, never have and never will. I consider it cheating

It used to be cheating.

Do you still touch the wall with your hand on freestyle turns? Do you let your head go underwater on breaststroke?...

Anything that can be done to make that stroke faster is a plus.

Bless you Kitajima you cheater you.

Midas
October 22nd, 2008, 05:17 PM
It's good to see validation, but I thought most breaststrokers now did a butterfly kick during their pulldown. What I want to know is when is the optimal time to do it. I've had this debate before, but Kitajima and Liesel Jones both do their butterfly kick BEFORE their pulldowns. Most Americans do their butterfly kick near the end of their pulldowns. Arguably, doing the butterfly kick first is not consistent with the rules (and if so, the rule should be revised to clearly permit this). It FEELS faster to me to do the butterfly kick first, but I don't know if this is true for a fact. My times don't appear to bear that out, though clearly there are many factors to take into consideration...

It's not hard to do the butterfly kick near the end of the pulldown, since the pulldown is close enough to a butterfly pull that the kick can feel very natural. It sounds like at a minimum, everybody should at least do that.

scyfreestyler
October 22nd, 2008, 05:18 PM
Did this really need a study to confirm the benefits? :dunno:

jim clemmons
October 22nd, 2008, 06:00 PM
Did this really need a study to confirm the benefits? :dunno:

Maybe had some funds that needed spending. Maybe the type of "use it or lose it".

hofffam
October 22nd, 2008, 06:14 PM
Correct, never have and never will. I consider it cheating. But I don't do meets anyway. If I do a 200 br 1.5 sec faster in practice (our practice clock doesn't even measure lower than a second), and it is because of doing something I don't believe in, what did I gain?

Occasionally when I'm doing breast, the coach will ask me about this, and I just ignore him. Eventually he works with me elsewhere in my stroke. He recently helped me with a change to my arm sweep during pushoff which had a pretty immediate impact.

I must comment that I don't understand your position. A legal turn is part of the stroke. So do you consciously make no attempt to improve your turns? Do you only try to improve the swimming portion? The single dolphin kick has been legal for over two years.

No one has to do the dolphin kick - or even an underwater pull and kick. But why not try it since it is in the rules and the evidence shows it is faster?

Steve Ruiter
October 22nd, 2008, 07:03 PM
Did this really need a study to confirm the benefits? :dunno:

Necessary: no.

But its good science to confirm and measure things, even if they seem obvious. You never know what you might learn.

Allen Stark
October 23rd, 2008, 01:32 AM
I really don't understand the big deal with doing or not doing this kick. As I've indicated, I don't swim in meets. As long as I'm not disrupting the workout, what's the big deal if I don't do it? Truthfully, I've never seen anyone else do this kick during workouts either.

We have swimmers who don't do flipturns, don't do assigned strokes, etc. As long as they don't disrupt the lane, it all works fine.

Did your first post get deleted?I only see it from other quotes.If you don't race I am not clear what your point is.
As to why do the study,it is important to quantify things.What if the study showed no improvement? You can't be sure until you test.
The first meet I swam in after the rule change was SCM and in the 200 BR I was really out of air the last 50 because I wasn't used to the extra time underwater.IF you swim meets you need to do in practice what you do in a meet and if something is legal and faster why not use it.
By USMS rules the dolphin kick can't be done before beginning the pulldown.

alphadog
October 24th, 2008, 10:01 AM
I start my dolphin kick smack in the middle of my pull so that it coincides with the finish of my pull. (am I alone in this?) I also allow my upper body to drop slightly (like going over a barrel)to set up a powerful kick. The feeling I get is that it increases propulsion and keeps me from coming to a complete stop as I raise my ankles to kick. This feeling is so strong that I would do it regardless of the results of the study.

Glider
October 24th, 2008, 12:20 PM
Exactly what I *try* to do...a very slight pike to set it all up.


I start my dolphin kick smack in the middle of my pull so that it coincides with the finish of my pull. (am I alone in this?) I also allow my upper body to drop slightly (like going over a barrel)to set up a powerful kick. The feeling I get is that it increases propulsion and keeps me from coming to a complete stop as I raise my ankles to kick. This feeling is so strong that I would do it regardless of the results of the study.

daveindc
October 24th, 2008, 02:35 PM
Ok, question to make sure I don't get DQ'd this Sunday...can I dive in, do an SDK, then underwater pull, then breaststroke kick to the surface?

poolraat
October 24th, 2008, 02:47 PM
Ok, question to make sure I don't get DQ'd this Sunday...can I dive in, do an SDK, then underwater pull, then breaststroke kick to the surface?


Here is the section of the rules that apply:



Kick—After the start and after each turn, a single butterfly (dolphin) kick,
which must be followed by a breaststroke kick, is permitted during or at
the completion of the first arm pull. .....

As an official, if I see the dolphin kick before the start of the arm pull I would disqualify the swimmer.

If you have any doubts or questions, ask the meet referee how they are interpreting this rule before the meet begins.

abc
October 24th, 2008, 03:31 PM
Did this really need a study to confirm the benefits? :dunno:

I'm with you on this one. Seems like a waste of time to me.

Midas
October 24th, 2008, 07:55 PM
Here is the section of the rules that apply:



Kick—

After the start and after each turn, a single butterfly (dolphin) kick,
which must be followed by a breaststroke kick, is permitted during or at
the completion of the first arm pull. .....

As an official, if I see the dolphin kick before the start of the arm pull I would disqualify the swimmer.

If you have any doubts or questions, ask the meet referee how they are interpreting this rule before the meet begins.



Sadly, this is the current rule. Given that the Olympians do their butterfly kick first under a similarly worded rule, I would hope that USMS officials, of all officials, would honor this in the breach. Clearly not all will, so it's a risk.

By the way, no offense meant to Poolrat or other officials. This is just a touchy subject for me. He is obviously making the "right" call based on the rule as worded. I just hate that Olympians can do this and I can't. :mad:

knelson
October 25th, 2008, 12:48 AM
Sadly, this is the current rule. Given that the Olympians do their butterfly kick first under a similarly worded rule

I think there's a little gray area in that the kick might be considered to occur only when the legs start to go down. Remember there's wording in there about a "downward dolphin." The wording has been changed slightly, but there is still mention of this. So, if this is true, these swimmer might look to be doing an illegal kick, but if they start the downward portion of the kick to coincide with the arm pull then it might actually be legal.

Here's the FINA rule:

SW 7.4 During each complete cycle, some part of the swimmer's head shall break the surface of the water. After the start and after each turn, the swimmer may take one arm stroke completely back to the legs. The head must break the surface of the water before the hands turn inward at the widest part of the second stroke. A single downward dolphin kick followed by a breaststroke kick is permitted while wholly submerged. Following which, all movements of the legs shall be simultaneous and in the same horizontal plane without alternating movement.

Interpretation: A dolphin kick is not part of the cycle and is only permitted at the start and turn whilst the arms are pulling back to the legs or after the arm pull whilst wholly submerged followed by a breaststroke kick.

Midas
October 27th, 2008, 12:05 AM
I think there's a little gray area in that the kick might be considered to occur only when the legs start to go down. Remember there's wording in there about a "downward dolphin." The wording has been changed slightly, but there is still mention of this. So, if this is true, these swimmer might look to be doing an illegal kick, but if they start the downward portion of the kick to coincide with the arm pull then it might actually be legal.

Here's the FINA rule:

I was under the impression that there was some official USMS interpretation which makes it clear that you can't do the dolphin kick first. It doesn't appear to be in the USMS rule book, however.... If this is a close call, I'm not sure why any officials would be calling a DQ on it, given that the Olympians seem to be permitted to do it...

Here's the USMS Rule:


Kick—After the start and after each turn, a single butterfly (dolphin) kick, which must be followed by a breaststroke kick, is permitted during or at the completion of the first arm pull. Following which, all movements of the legs shall be simultaneous and in the same horizontal plane without alternating movement. The feet must be turned outwards during the propulsive part of the kick. A scissors, flutter or downward butterfly (dolphin) kick is not permitted except as provided herein. Breaking the surface of the water with the feet is allowed unless followed by a downward butterfly (dolphin) kick.

I'd argue that if the kick and the commencement of the pull are pretty close to one another, it's hard to argue that the kick didn't occur during the pulldown. I really don't see why people should be DQ'd over this. I worry that the reason that people don't like this is because Kitajima does it, but he's not alone. Liesel Jones also clearly did it and I'm sure other non-Americans do it too. Why fight the progress of the stroke?

mattson
October 28th, 2008, 11:57 AM
Why fight the progress of the stroke?

What happens when someone decides to dolphin-kick at the beginning AND a the end of the pull? Is that progress, or just cheating?

pwolf66
October 28th, 2008, 12:15 PM
What happens when someone decides to dolphin-kick at the beginning AND a the end of the pull? Is that progress, or just cheating?


That would be TWO dolphin kicks and a violation of the stroke rules.

Midas
October 28th, 2008, 01:46 PM
That would be TWO dolphin kicks and a violation of the stroke rules.

The rules have to be reasonable, and that's a matter for debate surely. Just like the 15 meter dolphin kick rule in the other strokes, when the use of dolphin kick on the breaststroke pulldown gets pushed too far, the rules will prohibit it (or continue to prohibit it as it were). I don't think doing the dolphin kick at the initiation of the pulldown is pushing it to far. Just my opinion, though. (Well, mine and Liesel Jones's and Kitajima's, and the Olympic officials', etc.)

mattson
October 30th, 2008, 01:42 PM
That would be TWO dolphin kicks and a violation of the stroke rules.

Yes, and it used to be that ONE dolphin kick was a violation of the stroke rules. I was trying to point out that there was a difference between progress (like the Berkoff blastoff) which wasn't anticipated by the current rules, versus trying to legalize your particular crime. :)

I believe that the single breaststroke dolphin kick was added, in part, because it was hard to judge whether it was part of the normal body undulation motion during the pull-down. If the kick is added before the pull-down, why wouldn't someone add a 2nd "subtle" kick during the pull-down?

pwolf66
October 30th, 2008, 02:07 PM
Then I guess I'm not sure about your point. Why not make it 3,4 or more?

You stated the supposed reason why the single kick was permitted but what would be the rationale for adding more than that?

Paul

mjgold
October 30th, 2008, 02:15 PM
He's saying they made it legal because it was hard to judge whether or not someone was doing a dolphin kick or just undulating. His point is that someone could do the dolphin kick before the pull and then sneak in a second one at the end of the pool, making it look like it's just an undulation. So, assuming I'm correct in communicating his point, he's basically asking where does it stop?

mattson
October 30th, 2008, 05:09 PM
So, assuming I'm correct in communicating his point, he's basically asking where does it stop?

Aye. Midas was pointing was pointing out that a few people are pushing breaststroke "progress", but I think there is a real risk of the rules breaking instead of bending.

Then again, my breaststroke is flat enough, I wouldn't mind if they rolled back the rules to requiring your head to stay above water the whole time. :violin:

Midas
October 30th, 2008, 05:37 PM
I think the "it's hard to tell the difference between a kick and natural undulation" rationale for the rule change is an ex post facto justification for permitting something that was clearly illegal when we first noticed Kitajima doing it. And doing the dolphin kick at the initiation of the pull down is definitely the next step down the slippery slope. But we can certainly stop the slide at one kick, regardless of when it is done. If necessary, they should have a judge looking at an underwater camera at major competitions. At minor masters meets, nobody should get disqualified for this.

I enjoy doing the dolphin kick and don't want to revert to the "old" way (if you couldn't tell!).

stillwater
October 30th, 2008, 06:04 PM
As much as I hate to admit, I am forced to swim the slowest of stokes on dreary days.

I never thought of doing a dolphin kick before my underwater pulldown till I read it here. So I gave it several shots.

Seems to me that it is faster than the one oomph I always give in the middle of the pull down. This is purely a subjective point of view, not one bit of fact to support my feelings.

My affinity for air is always a big issue with me. I gather a balance of speed vs. my love of oxygen will dictate my future.

Paul Smith
October 30th, 2008, 09:59 PM
It's the best thing that has ever happened to the stroke that was created to give drop out gymnasts and divers something to do!

I went 15 yds off the start with one dolphin kick not long ago...add flip turns into this supposed stroke and I might actually consider it being allowed into the real world of swimming!

PS; I tried to do a grab start and flip turn off the 3m boards the other day at ASU and was tossed out of the "workout"...why do we still allow these orphans lane space?

knelson
October 31st, 2008, 12:14 AM
...add flip turns into this supposed stroke and I might actually consider it being allowed into the real world of swimming!

The flip turns are a good idea, Paul. I think you should be able to switch to freestyle once you get within the flags! Heck, I say the same rule should apply to backstroke, too. :)

BillS
October 31st, 2008, 11:31 AM
I think the "it's hard to tell the difference between a kick and natural undulation" rationale for the rule change is an ex post facto justification for permitting something that was clearly illegal when we first noticed Kitajima doing it. And doing the dolphin kick at the initiation of the pull down is definitely the next step down the slippery slope. But we can certainly stop the slide at one kick, regardless of when it is done. If necessary, they should have a judge looking at an underwater camera at major competitions. At minor masters meets, nobody should get disqualified for this.

I enjoy doing the dolphin kick and don't want to revert to the "old" way (if you couldn't tell!).

The double dolphin is already happening. Check out the last turn in the men's A Final 100 breast from the UW v. Cal dual meet:

http://www.floswimming.org/videos/coverage/view_video/234228/77113

It's pretty obvious, even without Garrett calling it out. I don't know how the stroke & turn judge missed it.

Midas
October 31st, 2008, 01:27 PM
The double dolphin is already happening. Check out the last turn in the men's A Final 100 breast from the UW v. Cal dual meet:

http://www.floswimming.org/videos/coverage/view_video/234228/77113

It's pretty obvious, even without Garrett calling it out. I don't know how the stroke & turn judge missed it.

Hmmm... I really couldn't see it and the judge was looking at another lane, so the judge must have missed it too...