Journal of Sports Sciences, article on lunging.

[Epee Scherma]

I found this article through a research database...

Journal of Sports Sciences, Feb 2005 v23 i2 p105(1)
111. The kinematic determinants of speed in the fencing lunge. (Part I. Biomechanics) S.L. Stewart; B. Kopetka.
Full Text: COPYRIGHT 2005 E & F N Spon

The lunge plays an important role as a major skill in fencing where it forms the basis of one of the most definitive attacking moves. It is initiated by the extension of the elbow and shoulder of the sword arm. This initial movement is followed almost immediately by extension of the front knee. Only when these extensions have been initiated does the whole body then move forward driven by a vigorous extension of the back leg.

The purpose of this study was to determine which kinematic variables within the performance of the fencing lunge have the greatest effect on the overall speed. The independent variable was therefore the time taken from the initiation of the first movement to the impact of the tip of the blade on the target. The six dependent variables were the maximum angular velocities of the elbow of the sword-arm, and the right and left knees, and the time taken to achieve maximum angular velocity from rest.

Fifteen elite epee fencers were filmed (shutter speed= 1/1000th second, frame rate=50 Hz) performing fencing lunges as fast as possible against a static practice lunging pad in response to a light stimulus. The video clips were then cropped and digitised according to a 24 point 14 segment spatial model using Peak Motus motion analysis software. Raw co-ordinate data were smoothed using a 4th order quintic spline algorithm.

The independent and dependent variables were then derived. The only dependent variable found to be significantly related to total lunge speed was the maximum angular velocity of the right elbow (r=0.620, P=0.018, 2 tailed). A paired linear regression was undertaken between the total speed of the lunge and the six dependent variables, however again only the maximum angular velocity of the right elbow was found to have a significant influence of up to 33.2% on the overall speed of the lunge, (adjusted [R.sup.2]=0.332, F7.475, beta=0.620, T=2.734, P=0.018, 2 tailed).

A combined multiple regression analysis was then carried out on the dependent variables. This predicted 59.4% of the overall speed of the lunge, (adjusted [R.sup.2]=0.594, F=4.171, P=0.042, 2 tailed). In this model, although the maximum angular velocity of the left knee was not significant (P=0.220, 2 tailed), the time taken for the knee to reach maximum angular velocity was significant at the 5% level (P=0.022, 2 tailed). Similarly, although the contribution of the maximum angular velocity of the right elbow was not significant (P=0.086, 2 tailed) the time taken for the elbow to reach maximum angular velocity was significant at the 5% level (P=0.047, 2 tailed). This was supported by the beta values (left knee = 1.106, right elbow=0.789) that were the highest of the six core dependent variables, suggesting that despite not having a high correlation (P > 0.05), these two variables do have a significant effect on the overall speed of the lunge.

It was concluded that the overall speed of the lunge is dependent on not so much how fast the maximum angular velocities of the sword arm elbow and knees are, but how soon they can be reached.

S.L. Stewart (1) and B. Kopetka (2)

(1) Division of Psychology and Sports Science, Wynne Jones Centre, Northumbria University, Newcastle Upon Tyne, NE1 8ST, (2) Team Northumbria, Wynne Jones Centre, Northumbria University, Newcastle Upon Tyne, NE1 8ST


Article A128604371

[Chafunkta]

Originally Posted by Epee Scherma

It was concluded that the overall speed of the lunge is dependent on not so much how fast the maximum angular velocities of the sword arm elbow and knees are, but how soon they can be reached.

So you're saying that to perform a fast lunge I have shorten the time it takes me to lunge? Seems the answer is in the question.



Good job with the derivations.

[ReverseLunge]

Did Grasshopper write that article?

[Teme]

Originally Posted by Chafunkta

So you're saying that to perform a fast lunge I have shorten the time it takes me to lunge? Seems the answer is in the question.

I think Epee Scherma is not saying much, but Stewart and Kopetka (the authors of the article) are

And they're actually saying that it's the acceleration (angular velocity reaching maximum from zero in shortest time), not velocity that defines the 'speed' of lunge.

[JEC]

In a different article, other investigators found that the time to recognition of the opportunity (reaction time) is the main determinant for the speed of the lunge. It does not seem to have been measured here.

It appears to me that once the "coordinated" movement starts, it is a chain of learned events, but the first movement "elbow extension" still is modulated, probably by the speed and certainty of the "cognitive decision" of an opportunity.

I'm glad that there is continued investigation into science of fencing actions.

See these two prior threads:

http://www.fencing.net/forums/fencin...sion/t8338.htm

http://www.fencing.net/forums/discus...ive/t1113.html

[Mr Epee]

I assume that was co-written by Kopetka Bela, who is a fairly well known Hungarian coach. I think he was originally a pentathelete. I wasn't aware that he was in England, but last I recall - he was Geza Imre's (Atlanta Bronze Medalist) coach, and daytime taxi-cab driver.

I may be able to use this data for some projects. I'll have to research the source a little, and it always disturbs me that they use the term 'elite fencers' in these projects, but rarely define the term.

Thank you very much for sharing.

[Gav]

Originally Posted by MR Epee

I wasn't aware that he was in England ...

Thre is a coach going by that name floating around England... Whether it's the same guy I couldn't say.

[pigeonmeister]

Originally Posted by Mr Epee

I assume that was co-written by Kopetka Bela, who is a fairly well known Hungarian coach. I think he was originally a pentathelete. I wasn't aware that he was in England, but last I recall - he was Geza Imre's (Atlanta Bronze Medalist) coach, and daytime taxi-cab driver.

I may be able to use this data for some projects. I'll have to research the source a little, and it always disturbs me that they use the term 'elite fencers' in these projects, but rarely define the term.

Thank you very much for sharing.

I know the Northumbria University team quite well, having fenced against them for Birmingham University (and beat them 3/3- sorry had to mention). The last time was 6 weeks ago and they did have a highly rated Hungarian coach, but I can’t remember his name- I assume it was Bela.

In terms of ‘elite’ if they used the University team then that includes Peter Kirby who is a sabreur who has fenced at the junior worlds and would probably be included in the top 15 most talented sabreurs in the UK. They also have a couple of other fencers who are about UK top 50 standard. They could have used Chris Buxton, who left Northumbria Uni at least a year ago, and has been British number 1 and almost definitely will make senior worlds in the near future.

Northumbria Uni (which is in the city of Newcastle) is very close to Durham and at Durham Uni there is another Hungarian sabre coach by the name of Laszlo Jakob who might have provided a few other fencers (maybe Chris Farren- another former British number 1 or Ricky Brenda who has fenced at a very high junior level). It’s all sabre in the North East of England really- no ‘elite’ foil to speak off.

I’d take ‘elite’ in this case to mean ‘elite in the UK’ or maybe ‘elite at junior/cadet international level’. I wouldn’t expect anybody in the senior top 50 in the world unless they were shipped in. Still awesome enough fencers in my opinion to provide very useful data.

[Sciurus-Rex]

Originally Posted by Teme

And they're actually saying that it's the acceleration (angular velocity reaching maximum from zero in shortest time), not velocity that defines the 'speed' of lunge.

But it would seem that given the very short period of time under scrutiny, the difference between "acceleration" and "maximum velocity" is so small as to be effectively meaningless.

In other words, the responses to the conclusion reached is, "Well, duh" and/or "So what?"

[JEC]

Originally Posted by Sciurus-Rex

But it would seem that given the very short period of time under scrutiny, the difference between "acceleration" and "maximum velocity" is so small as to be effectively meaningless.

In other words, the responses to the conclusion reached is, "Well, duh" and/or "So what?"

Nevertheless, the authors provide additional evidence that the most critical aspect is the acceleration of the first component of the lunge. That is to say, that in order to improve the most, reaction time (fencing more) is what matters, not how strong are your legs. The latter might be a modifiable critical variable to improve the length of your lunge (Obviously your arm length is not).

[PeterGustafsson]

Hi!

Originally Posted by Sciurus-Rex

But it would seem that given the very short period of time under scrutiny, the difference between "acceleration" and "maximum velocity" is so small as to be effectively meaningless.

Ehh.. No.

Acceleration is measured in m/s2, while maximum speed has the dimension m/s. I have given exactly zero points for stuff like that on machine element tests. Your should reread your kinematics course.


Have a nice time!

Peter Gustafsson

[jBirch]

Originally Posted by JEC

Nevertheless, the authors provide additional evidence that the most critical aspect is the acceleration of the first component of the lunge. That is to say, that in order to improve the most, reaction time (fencing more) is what matters, not how strong are your legs. The latter might be a modifiable critical variable to improve the length of your lunge (Obviously your arm length is not).

Actually, I took a different lesson from that paper.

It seemed to me to be saying that the speed of the lunge (ie// how long it takes to reach the target) is highly dependent on the initial accelleration of the weapon arm and NOT the extension of the bigger leg muscles. To me it's akin to first and second gear in a car (1st being the elbow, second being the leg). I didn't see anything about reaction time (though it seems odd to exclude it in the study).

Additionally, this makes it interesting to note the adage "arm first" is not just for tip control accuracy (as I had originally assumed) but also for overall penetration to target. That the more vigourously the arm is extended the less time it takes you to reach the target.

Also, the lunge is at full velocity when the rear leg and sword arm are fully extended. The point, therefor, of the front foot is merely to get the hell out of the way and provide a breaking effect on terminus.

Neat.

James.

[Sciurus-Rex]

Originally Posted by PeterGustafsson

Acceleration is measured in m/s2, while maximum speed has the dimension m/s. ...

Well, duh! EVERYONE knows the definitions of accel and velocity. And, yes, there are OBVIOUS mathematical differences in those dimensions. But as I said in my post, within the tiny time frame under consideration, those differences are EFFECTIVELY meaningless. i.e. "Hey, Jim, rather than working on improving the final speed of your one-third-of-a-second lunge, let's improve that acceleration phase instead."

[JEC]

Originally Posted by jBirch

Actually, I took a different lesson from that paper.

It seemed to me to be saying that the speed of the lunge (ie// how long it takes to reach the target) is highly dependent on the initial accelleration of the weapon arm and NOT the extension of the bigger leg muscles. To me it's akin to first and second gear in a car (1st being the elbow, second being the leg). I didn't see anything about reaction time (though it seems odd to exclude it in the study).

James.

That is what I said regarding this paper (see post #5). However, I added later (post #10) that probably the depthness (or length) of the lunge is probably dependant on the legs.

Regarding reaction time read the threads that I place the links for.

[Grasshopper]

Originally Posted by ReverseLunge

Did Grasshopper write that article?

Come on, if I wrote it, it would have much more zen-like oriental mystery to it. This is cheap paltry.

[ReverseLunge]

Originally Posted by Grasshopper

Come on, if I wrote it, it would have much more zen-like oriental mystery to it. This is cheap paltry.

Well the guys doesn't have yellow fever like you but he does like to state the obvious.

[Twinkletoes]

"It was concluded that the overall speed of the lunge is dependent on not so much how fast the maximum angular velocities of the sword arm elbow and knees are, but how soon they can be reached."
Journal of Sports Sciences, Feb 2005 v23

umm... ok.
Isn't that like saying " it wasn't how quickly he could extend but rather how quickly he could achieve extension"

um.. think of it grasshopper..do the math...you know I'm right.. kinda..

This conclusion baffles me... call me crazy. On the plus side I was a bit
surprised that the sword arm elbow max velocity played such a bit part. I would
have thought the left leg extension speed/time to be the primary factor.

Cheers

[KD5MDK]

No, they're saying (to use a car analogy)
If Car A has a top speed of 180 mph and Car B has a top speed of 120 mph, that's maximum velocity (for this study)
If Car A has a 0-60 time of 6 seconds and Car B has a 0-60 time of 4.2 seconds, that's how soon that speed can be reached.

It's not how fast you end up going, it's how long it takes you to get to that speed.

You know, a graph would help explain this. Too bad I'm off to bed.