Insole comparison
Springsoles vs VKTRY carbon fiber insoles
Two products, two completely different ideas about how a shoe should give energy back. One is a moulded carbon fiber plate that replaces your insole. The other is a patented rubber layer, 3/32 of an inch thick, fitted under a removable liner or on top of a fixed liner. Here is the honest breakdown, with every claim about another brand sourced to that brand's own site.
Made in the USA4 U.S. patentsmade in the USAThe short answer
Choose Springsoles if
- You compete in cleats or court shoes where there is no room for a plate.
- You want your factory fit and arch left exactly as it is.
- You want one pair that moves between shoes, sports and work boots.
- You want documented patents and named lab work behind the claim.
- You want to spend under thirty dollars to find out.
Choose a carbon plate if
- You want a structural, orthotic-class replacement insole.
- You have the shoe volume to give up and are happy refitting.
- You want stiffness matched to your body weight by the maker.
- Premium pricing per pair is not a concern.
These are different tools. A plate changes the structure under your foot. Springsoles changes the material your foot pushes into, without changing the shoe.
Side by side
| Factor | Springbak® Springsoles | Carbon fiber plate insoles (VKTRY) |
|---|---|---|
| What it is | A thin resilient energy-return layer made from a patented 1,4-polybutadiene rubber composition. It is a material, not a structure. | A moulded carbon fiber baseplate built into a full replacement insole. VKTRY describes its product as carbon fiber sports performance insoles with a patented carbon fiber baseplate. |
| Where it sits | Underneath the insole already in your shoe or cleat. Your factory fit, arch shape and volume stay exactly as they were. | In place of the insole already in your shoe. The stock insole comes out and the plate insole goes in. |
| Thickness and fit | 3/32 inch. No break-in period, no volume change, and the same pair moves between cleats, court shoes and work boots. | A structural plate is substantially thicker and stiffer than a stock insole, so fit and shoe volume change with it. |
| Sizing model | Sized by shoe size. Try untrimmed first; trim only the toe or forefoot if needed for a flat fit. | VKTRY selects a baseplate from five stiffness levels using body weight and age, and sells separate product tiers. |
| Cost per pair | made in the USA. Check current pricing on our shop page. | Priced as a premium orthotic-class product. Check vktry.com for current pricing rather than trusting any third-party figure, including ours. |
We publish no performance numbers for another company's product and no price we have not verified today. Where a figure matters to your decision, check it at the source below.
What is actually documented on our side
Four issued United States patents, filed by inventor William R. Crow and granted between 1996 and 2003, cover the energy-return composition and the components formed from it: 5,554,694 · 5,695,850 · 6,120,880 · 6,589,630 B1. The patent record is public and every filing is linked on our patents page.
In force-plate testing at the Weber State University human performance lab, it took more than twice the force to displace a person standing on Springsoles. Howard Gray, PhD, then Director of the Department of Gerontology at Brigham Young University, sponsored that work and concluded there is a significant strength increase for individuals using Springsoles. At the University of Southern California, Dr. Robert Wiswell found athletes in Springsoles took fewer strides over the same distance than in placebo inserts, consistent with increased stride length.
That is the whole claim, stated plainly: the proof page carries the study detail and the technology page explains what the patents protect and what stays a trade secret.
Force-Plate Stability Study
In force-plate testing, subjects standing on Springbak® Springsoles showed more than twice the overall resistance to being pushed from their position.
In plain English: they were harder to move. They could hold their ground better against a sideways push—exactly the kind of stability athletes need when planting, cutting, jumping, landing, and absorbing contact.
Springbak® gives the foot a more stable, responsive platform to work from inside the shoe.
Results are from the force-plate testing described in U.S. Patent No. 6,589,630 B1. Individual results vary.
Coaches who tested it on their own rosters
These endorsements were not bought in an ad campaign. Head coaches tested Springsoles with a speed gun, a gym full of jumps and national titles on the line — and a Hall of Fame cornerback put his name to the result. Quotes appear exactly as Springbak has always published them.
Hugh McCutcheon
Minnesota / USA Volleyball
Former head coach, University of Minnesota volleyball; former USA Volleyball head coach; assistant coach at BYU when he tested Springsoles
Olympic gold (2008 men) and silver (2012 women) as USA head coach
“While an assistant coach at BYU I tested spiking speed of our men's volleyball team with a speed gun. After an hour of testing it became apparent that they were hitting 5% faster in Springsoles.”
Hugh McCutcheon reported the approximately 5% faster spiking figure from that speed-gun session at BYU; it was not a vertical-jump measurement.
John Cook
Nebraska volleyball
Former head coach, University of Nebraska volleyball
Four NCAA national championships at Nebraska
“There is no doubt in my mind after testing and hearing the athlete's feedback that your innersoles help our athletes jump higher and move quicker.”
A coach's reported observation from his program's own testing and athlete feedback — not a laboratory measurement. Individual results vary.
Carl McGown
BYU men's volleyball
Former head coach, BYU men's volleyball (1990–2002); longtime USA Volleyball national-team coach
Two NCAA national championships at BYU (1999, 2001); Volleyball Hall of Fame
“We love Springsoles from Springbak®. We have been using them for an explosive team.”
In memoriam — Carl McGown passed away December 30, 2016, at age 79. A coaching icon whose technique teaching shaped generations of American volleyball.
Champ Bailey
Denver Broncos
Cornerback, Denver Broncos and Washington; Pro Football Hall of Fame, class of 2019
12-time Pro Bowl selection, 52 career interceptions
“I can run faster, jump higher, and have less fatigue. I would highly recommend Springbak® Springsoles to enhance athletic performance.”
Todd Christensen
Raiders / BYU
Former BYU and Raiders tight end
2-time champion, 2-time NFL receptions leader, 5-time All-Pro
“One innovative idea grew into a patented, ultra-thin performance product used by athletes across many different sports.”
Portrait from Springbak's legacy film.
Quotes as published on springbak.net. Coaching titles reflect the programs these coaches led; endorsements are personal and do not imply endorsement by any university, athletic department, national federation, the NFL or any club. Photographs are Springbak's own testimonial images; team and university marks visible in them belong to their respective owners. Individual results vary.
On the record
On the record
Researchers, coaches and athletes on the Springbak® approach.
“Our department sponsored a strength and stability study at the Weber State University human performance lab. After reviewing the force plate data, showing it took more than twice the force to push off the subjects off the force plate when standing on Springsoles, we have to conclude there is significant strength increase to individuals utilizing Springsoles.”
Questions athletes ask before switching
Is Springsoles a carbon fiber insole?
No. Springsoles is a patented rubber energy-return material, not a carbon fiber plate. A carbon plate works by being stiff and springing back structurally. Springsoles works chemically: a 1,4-polybutadiene composition that returns energy rather than only absorbing it, in a layer 3/32 of an inch thick.
Do I take my existing insole out?
Remove a factory liner only when it is removable or releases cleanly with a gentle, steady pull. Stop if it starts to tear, stretch or deform. Never force out a firmly bonded or stitched liner; leave it in place and put the Springsole on top. A plate insole replaces your stock insole, which can change shoe volume and arch shape.
Which one is better for cleats?
Cleats have very little internal volume, which is why Springsoles are 3/32 of an inch. Put them under a removable liner or on top of a firmly bonded or stitched liner, and confirm they lie completely flat. Our sport pages cover each footwear type.
What evidence does Springbak have?
Four issued U.S. patents (5,554,694, 5,695,850, 6,120,880 and 6,589,630 B1) and named laboratory work. In force-plate testing at the Weber State University human performance lab, it took more than twice the force to displace a person standing on Springsoles. At USC, Dr. Robert Wiswell found athletes took fewer strides over the same distance than in placebo inserts.
Why is Springsoles so much less expensive?
There is no moulded structure, no stiffness-tier inventory and no custom fitting step. It is a material layer manufactured in the USA and sold as one version you trim to your shoe size.
Can I use both at once?
We do not recommend stacking Springsoles under a structural plate insole. The plate already fills the volume a shoe has to give, and a rigid plate is not the surface Springsoles is designed to work against. Use Springsoles under a normal factory or foam insole.
References & sources
Try the cheaper experiment first
Try one pair untrimmed first, then fit it according to your shoe’s liner type. Trim only the toe or forefoot if needed for a completely flat fit.
Still deciding? Ask us directly.
Tell us your sport and the shoes you compete in and we will tell you honestly whether Springsoles fits them.