I was thinking the other day about running shoes and how in golf equipment, namely your driver, the big dog, you have a maximum coefficient of restitution for the club face; 0.83. Coefficient of restitution for a measured object being the ratio of relative speeds before and after a collision, along the line of collision, where zero is a dead stop (relative to one another) and 1 is perfectly elastic. In golf this limits the elasticity of the driver face and was brought about because it was deemed an unfair advantage if the club face was too “springy”.
When is a shoe too “springy”? By all accounts and according to the many threads on here these Hokas, as an obvious example, manage to be extremely cushioned without feeling dead underfoot. So I assume they have a fairly high “COR” when worn by a person and don’t simply absorb and dissipate the energy. I see the Hoka, and any shoe for that matter I might add, as being on a scale somewhere between a pair of flat canvas plimsolls and these…
How far along that scale can you go before it is unfair? And is it a matter of time before the “springiness” of a pair of running shoes is limited by a governing body?
Caveat to the above - I understand that you probably have to consider the runner + the shoes in any consideration of COR, and also that the running mechanics involved mask the effect in any real world scenario. It’s one of them hypothetical jobs.
Genuine question. And to be clear, I’m not accusing any Hoka runners of cheating! It’s just a thought I done thinking.
This is not a new idea. If it worked someone would have figured out a way to make it work. But why doesn’t it?
Would more bounce always result in more vertical movement, a lower cadence and less horizontal movement?
(It seems that a pogo stick and a trampoline work primarily by allowing vertical momentum to increase further than normal). I am not sure how that might be converted to horizontal movement. Maybe a spring loaded eliptical? That might accelerate faster than a bike?
I am wonndering when they will put carbon fiber springs that look like Blade Runners springs into shoes somehow. I feel like the Hoka platform could handle something like that. The problem is I think they are optimized when running really fast at a certain weight so the compression and release of energy are timed right. STers would kill for carbon blade hokas though.
The Skechers Gorun Meb Speed 2 race shoes have a carbon fiber plate in them for energy return. Not sure if it makes you faster, but it does make for a very responsive shoe.
The very design and technology of the SPIRA Stinger Competition shoe has led it to be banned by the USATF and the Boston Marathon in 2006, sighting shoes containing spring technology are considered to provide an athlete with an unfair advantage. The company (Spira) filed a lawsuit against the International Amateur Athletic Federation and the United States Association of Track and Field, alleging that their Rule 143 – which bans shoes with springs – constitutes a violation of the Sherman Anti-Trust Act and a restraint of trade. Krafsur said, “Often, the rules of sports don’t keep pace with technological advances. But the benefit of our technology is better shoes not just for dedicated runners but for everyone.” Though banned by the IAAF and USATF, they have not disqualified anyone who races in the shoe.
The very design and technology of the SPIRA Stinger Competition shoe has led it to be banned by the USATF and the Boston Marathon in 2006, sighting shoes containing spring technology are considered to provide an athlete with an unfair advantage. The company (Spira) filed a lawsuit against the International Amateur Athletic Federation and the United States Association of Track and Field, alleging that their Rule 143 – which bans shoes with springs – constitutes a violation of the Sherman Anti-Trust Act and a restraint of trade. Krafsur said, “Often, the rules of sports don’t keep pace with technological advances. But the benefit of our technology is better shoes not just for dedicated runners but for everyone.” Though banned by the IAAF and USATF, they have not disqualified anyone who races in the shoe.
Cheers,
Neal
+1 mph Faster
Spira was never banned. That is just a market hoax fabricated by Spira. Their shoes aren’t even fast.
I kind of remember a gas powered pogo stick from years ago. I think it may show up on lists of most dangerous toys ever. When you jumped on it the force compressed the air gas mixture and it somehow fired (sparkplug?) giving the rider a big bounce.
If you could build shoes along that line that would be unfair. If you survived.
