I did this very thing for my son's poles. He had at least three different manufacturers and no consistency on their flex numbers. He even had a handful of 16 foot and 16'6" poles and by measuring them all the same width I had a more accurate reference to "grade" upward his series of progressive flexes. I was able to tell him with certainty which pole was softer or (how it really paid off) was when he need to move up a pole, which one was the next in the series regardless of the length difference (just grip the same height). I got this tip from Tye Harvey when he was in the hunt for an Olympic spot. Credit goes to him.
After 4 years I finally understand how to read flex numbers and what they mean. The thing I currently struggle with is trying to compare flex numbers to other brands. My top girl last year went from a 12'6" 140 Altius (super soft) to a 12'6" 140 and a 13'140 Pacers and struggled with them. Now this year before everything got cancelled, she rented a 12'7" 150, a 13'1" 145, and a 13'1" 150 Essx poles. She had never been on anything bigger than a 140 pole so it can be maddening trying to figure all of this stuff out. Would you consider UCS and Essx poles kind of middle of the pack as far as softness vs stiffness goes? I want to get a good selection of poles, but I don't want to get poles that are too stiff which Pacer seems to be the stiffest, or too soft which I would consider Altius.
Not to mention the can of worms, sail geometry. 😝 I use to measure with a span going from 4 inches of the bottom to 6 inches from the top. Bottom end static and top end rests on a roller, allowing it to flex unimpeeded and consistent. Got mostly Pacers (FX, FXV and CarbonFX) and a few Nordic.
Team Hoot Pole Vault Certainly. Geometry of the various pieces of glass, carbon or whatever, is what makes poles bend differently. Pre bend is added prior to full curing, and possibly it can make some poles twist slightly while bending.
Team Hoot Pole Vault Vaulters of today are spoiled. My friend and mentor, Wojchiech, tells tales of him and Slusarski sharing two poles for the 1972 Olympics.
You just told me what I’m doing this afternoon w/ 5 poles 14’-6” 165# from soft to stiff by using the 2.54 division to convert them into cm. it looks like this. (Softest 1-Sky Pole, 2-Altius, 1-Essx , 1-Spirit stiffest) Gill poles Pacer,Sky Poles are in inches. But the vaulter says by the feel of the pole bending vaulting that the Sky Pole is #3 & not a #1. I’m heading out to experiment. I’ll let you know my findings. Good call. Thx
Thanks Shawn. Great channel and post. I totally agree with you that there should be international testing and labeling standards that all pole manufactures should follow for flex number and for weight rating (or some other rating system), that takes performance and safety into account. That being said, without getting all sciencey, neither alone is sufficient to describe a pole dynamics and safety. Flex number is stiffness (Youngs elastic modulus, or spring constant), not its ultimate strength (yield with safety ratio). Weight rating is a simplification, as it has no information on the energy a vaulter might impart into the pole with the run and jump. A 220lb footballer running slowly is not the same as a 165# tall sprinter. A long run and a short run are not the same dynamic energy, why would you use the same weight rated pole? I feel that a [maximum] weight / safety rating is needed to ensure a degree of safety in the sport. However, it is sort of useless for picking a pole for success and progressions all by itself. Flex number is way better aligned for that. I encourage anyone that cares, to measure the flex of all their prospective poles (with the proper pole orientation down) from the base to the upper hand position. Just use a consistent weight dangled from a cord for each, exactly in the center. The deflection progression will be the stiffness progression (not exactly linear as the weave is not uniform and the bend arc is an arc (not a small angle). And remember, a stiffer pole is a faster pole (wind up and unwind), so the standards will likely move in and less depth in the pit.
You nailed it! Butnto keep it simple, My take is that with some sort of a universal flex system vaulters are more likely to know what their next pole is which will keep them safer. Most kids here in the states go based on the weight label alone. To me its like trying to guess the next weight in the weight room without any numbers on the weights. I'm simply saying, universal flex numbers are more helpful than random weight labels nd flex numbers we have now for knowing the, next pole.
There's more than one flex number on a pole. So where is the first, second, third, and forth flex number located on the pole? I'm assuming the first number is closer to the top of the pole, but that's just a guess and this video makes it seem like there's only one flex number on a pole and it's talking about the flex of the center point
You can shoot me an email if you uave questions. But there's usually only one flex number. The other numbers could be thre model number, Date manufactured, length etc. I'd imagine yours would he between 14.0 and 26.0
@TeamHootPoleVault my coach just explained to me that the 2nd number is the flex number. Thanks for letting me know, this makes everything much easier!
Thanks, Shawn, for that explanation! Enjoying your book! Wishing I could be using your training program I bought for my team. Got like 2 days into it before everything shut down. Stay safe and healthy! Thanks again!
Does the flex number change as you lower/higher your grip just like the weight label? I thought it would, but if the width is always the same for different length poles then the flex should be the same?