it's the asymetric banks. steeper at beginning with a longer downhill fade. requires ~4 steps on the rise and gives you ~8 on the down hill. Plus has wood frame vs concrete/steel to create bounce.
Asymmetrical banks as you describe makes sense. Is it true?
I always thought Arkansas track was very fast based on highly competitive meets that produce record times. Seems as though their turns are wider too. The meet announcer occasionally states that its the fastest i door track in the world as well.
It's absolutely true. There was a great article that was here maybe a year or so ago about the guy who engineered it and his goal was simply to make the fastest running surface possible. The frame is wood with the track sitting on plywood - sheets which are flexible and resilient as well at the famous asymmetric banking on the curve that takes advantage of your momentum coming off the straight as you make the "climb" and then offsets the disadvantage of running a curve with it's longer "downhill" exit.
It's a genius design and it works. It's so good it's almost certainly the fastest surface to run on in the world when you throw in perfect climate control. I wonder what would happen if these guys rocked up in August to a meet to really go after times - I would guess a lot of PR's would be set (and I mean irrespective of indoor or out).
I am curious. What are these "stringent testing and ticking of boxes first to make sure they are within the boundaries of what is legal and what's not."? In post #14 I quoted the Technical Rules on indoor track surfaces. They are very loose and open to a lot of creative interpretation. For example:
without any special sprung sections
Does this imply sprung sections are OK, so long as they are not "special"?
as far as technically possible, each runway shall have a uniform resilience throughout
"As far as technically possible' is very vague. It is almost as if they are saying if you can come up with some sort of excuse you don't need to have uniform resilience. Also, there are no limits on the amount of resilience. It would be simplest to state that the resilience cannot be greater than that found on an outdoor track but that would eliminate any form of suspended or banked track as joist spacing will obviously affect resilience. Perhaps the rules could state the resilience cannot be more than 10% greater than an outdoor track?
This shall be checked, for the take-off area for the jumps, before each competition.
How is it checked? Are there force - deflection measurements taken or is it just a marshal walking around and going by feel? Again, very vague.
If you know of other rules and tests besides those published by WA I would really like to see them, because the current rules seem to rely on good will and that the designers of indoor tracks will just design them to be functional rather than fast. As was shown with the shoes if someone does decide to exploit the vagueness of the rules they can cause a major shift and leave the authorities rushing to play catch up.
Regarding the BU track. Did they design it to be fast or did they happen upon a combination of grades / thicknesses of plywood and joist spacing that made the track more resilient, I don't know?
See the following link, specifically page 102. All potential track surfaces undergo very strict laboratory testing before they are laid down
I am curious. What are these "stringent testing and ticking of boxes first to make sure they are within the boundaries of what is legal and what's not."? In post #14 I quoted the Technical Rules on indoor track surfaces. They are very loose and open to a lot of creative interpretation. For example:
Does this imply sprung sections are OK, so long as they are not "special"?
"As far as technically possible' is very vague. It is almost as if they are saying if you can come up with some sort of excuse you don't need to have uniform resilience. Also, there are no limits on the amount of resilience. It would be simplest to state that the resilience cannot be greater than that found on an outdoor track but that would eliminate any form of suspended or banked track as joist spacing will obviously affect resilience. Perhaps the rules could state the resilience cannot be more than 10% greater than an outdoor track?
How is it checked? Are there force - deflection measurements taken or is it just a marshal walking around and going by feel? Again, very vague.
If you know of other rules and tests besides those published by WA I would really like to see them, because the current rules seem to rely on good will and that the designers of indoor tracks will just design them to be functional rather than fast. As was shown with the shoes if someone does decide to exploit the vagueness of the rules they can cause a major shift and leave the authorities rushing to play catch up.
Regarding the BU track. Did they design it to be fast or did they happen upon a combination of grades / thicknesses of plywood and joist spacing that made the track more resilient, I don't know?
See the following link, specifically page 102. All potential track surfaces undergo very strict laboratory testing before they are laid down
I did see this but it only applies to outdoor tracks (Chapter 3). Chapter 8 covers indoor facilities and does not include any testing requirements. The section on Track Construction (Section 8.3.2) states:
The specifications in Chapter 3 apply generally to the synthetic surface of the track. However, the force reduction and vertical deformation properties will be different if the absolute thickness is less than the absolute thickness on the Product Certificate. The thickness of the synthetic material on portable oval tracks shall be not less than 9mm and on permanent oval tracks 13mm.
They are just talking about the surface. They state 13mm on permanent tracks as the assumption is they are laid on bare concrete, much like an outdoor track. They state 9mm for portable tracks as they assume these will be built on some joist and plywood base and so will have a some inherent elasticity not present in concrete.
If testing were to be carried out as per Sections 3.1.3.4 and 3.1.3.5 then the locations would need to be redefined as the back straight and main straight locations defined in the tests only apply to 400m tracks. Also there would need to be some requirement written in to tests at locations both above joists and at mid span points.
No, New Balance has their own new facility close by. It is amazing that Boston has 4 banked 200m tracks within about 10 miles of each other. They include Harvard, BU, Reggie Lewis and the new New Balance track. Harvard's track also has a wood support system, but their banks are symmetrical and are lower than the BU track.