h1

Why Computer Analysis And Not Just Slo-Motion?

August 27, 2007

One 0f the main uses of video analysis software with figure skaters is determining flight times.  Why?  Because flight time or jump height largely determines jump success.  For example, based on all the video that I have analyzed, I have never seen a double axel that had less than 0.467 seconds of flight time.  And other video analysis experts have confirmed this value.

Dartfish experts Chris Conte and Audrey Weisiger use a value of 0.500 seconds for double axel.  But I have personally measured a handful of double axels at 0.467 and in fact, one of the skaters I work with regularly in Madison lands it consistently with that flight time.  But she is very slender and has an awesome rotation rate.  So most skaters that are not as slender will probably have to meet Chris and Audrey’s 0.500 second minimum.

If a skater is ready to work on double axel but cannot perform a single axel with at least 0.467 seconds of flight time, she should spend nearly 100% of her effort making her jump bigger.  The chances are simply not good that she will be the first skater ever to land a double axel with less than 0.467 seconds of flight time.

This feature of video analysis software truly sets computer jump analysis apart from basic slow-motion video analysis.  Of course, basic slo-motion has been used by coaches for years and is very common in figure skating.  But computer analysis provides flight time and takes coaching to another level.  Knowing the flight time of the jump is critical for understanding what is possible.

All the time, I see skaters that are attempting double axels and triples that simply do not have the height necessary to land those jumps.  And unfortunately, they continue to practice them over and over, teaching themselves to fall or teaching themselves to land cheated jumps.  Since their coaches don’t realize they will never land it without more height, they keep doing it, and ingraining an incorrect movement that can be nearly impossible to change.

And that largely explains why double axel separates the really good skaters from the rest.  At the recent Frank Carroll  workshop in Milwaukee, Mr. Carroll described skaters having jumps and jump combinations through double lutz as being very good… but skaters with a double axel are in another class.

And that’s also evident in some surveys I’ve done.  Many coaches rarely get the chance to work on double axel.  And when they do, they are almost never successful.  The percentage of ladies that actually learn to do it consistently is very small indeed.  And no wonder… just getting any female athlete to jump 10.5 inches off one leg is quite a feat! (10.5 inches represents 0.467 seconds of flight time based on projectile motion calculations… more about that in a future post!)

And here’s some more astonishing but useful numbers.  Minimum flight time for double lutz is about 0.366 seconds.  That makes the difference in flight time between double axel and double lutz just 0.1 seconds.  But guess what?  Those 0.1 seconds represents a whole 4 inches!!!  So you can do a double lutz with just 6.5 inches of height but you have to jump over 60% higher to land a double axel!  No wonder so many skaters never get one…

If you have skaters working on double axel, do yourself and them a favor by getting a computer analysis done.  Find someone to help you if you don’t have the tools yourself.  The bottom line is – computer video analysis is truly a major leap forward in figure skating coaching for advanced skaters. 

Trevor

Advertisements

3 comments

  1. Trevor,
    Well written. Your point can be expanded to practically every form of athletics. I too use video analysis to help skill specific coaches, primarily baseball and softball to correct mechanics flaws.

    One of my biggest “pet peeves” is the number of seasoned coaches who think they can see and diagnose issues, then after using slow motion analysis you discover they totally missed the true cause and effect of the problem and therefore have been wasting the athlete’s time trying to correct the wrong problem, frustrating the athlete to no end in the process.

    I can only guess how that must impact the psyche of a teenage figure skater.


  2. I would like to see a continuation of the topic


  3. whats the average jump time and height for a single axel?



Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: