I previously blogged about the wishful thinking fallacy, pseudoscience and quackery claim that the first sub 2 hour marathon will be run barefoot 2 years ago and nothing since then has convinced me to change my mind. If anything, the opposite has been the case. My belief is that the running shoe that is used for the first two hour marathon is one that is tuned to the athlete.
The conclusion that I draw from all the studies on running shoes, cushioning and running economy is that it is subject specific. For some a minimalist shoe/barefoot is more economical and for others a highly cushioned shoe is more economical. So the shoe for the sub two hour marathon will probably have the right amount of cushioning for that runner.
Energy return from the shoe has the potential to play a key role as this is free energy. ‘Energy return’ midsole materials have been shown to improve running economy. The current five of the six fastest marathons have been run in such shoes. There is a reason for that.
Running shoes have different stiffness’s that can affect energy return and running economy, which also are likely to be subject specific and tuned to the individual athlete. The running shoe is probably also going to the tuned to the frequency of the muscles or soft tissue vibrations to minimize that, which will also probably affect running economy.
The reason I raise this now is the flurry of publicity in the last week from from Nike’s and Adidas’s attempt to be behind the first sub 2 hour marathon. In December 2014 a group started campaigning for the sub 2-hr marathon (but the announment which was here is gone, but snap shot is on the wayback archive). Their website is reporting on their progress and they did try to claim credit for Kenenisa Bekele’s Berlin time of 2:03:03. This project appears to have no partners in the running shoe industry.
Two weeks ago, Nike announced their plans for the sub-2 hour marathon, sooner rather than later. There has been plenty of analysis of that announcement. In the press release put out by Nike, they said:
Fueled by a long-standing passion for running, Nike began working on a footwear solution specific to the marathon in 2013.
What are they working on? In 2013, media reports commented on the $2 million running shoe that Nike were developing for Mo Farah’s marathon debut. Some snippets from the media report included:
A team of 25 people are working at Nike on developing shoes tailored for Farah’s running style.
“We are in the information-gathering stage,” said Farah’s coach Alberto Salazar. “The first meeting I went to there were 25 people on this project. They went to St Moritz to watch Farah train.
“It’s going to be a terrific shoe for Mo Farah to run in and could save a couple of minutes on his time. If you can change the crank on a bike to help you, if you can change the car, why not shoes?
“It’s hard to put a price on it. Multi dollars? Could be, the time, the expense, people all over the world, the research. This is a million-dollar project, yes.”
Not a lot more was heard about this effort until the press release that they have been working on a shoe since 2013.
More could be speculated from a patent that Nike were granted last month for a “Footwear sole structure including a spring plate”. Some snippets from the patent include:
As a result of ground contact during walking and running, the metatarsophalangeal joints in a person’s foot undergo an extension controlled by the joint flexor muscle-tendon units. Associated with this controlled extension is mechanical energy expenditure at the joint. In conventional footwear, little to none of this mechanical energy is recovered to contribute back to ongoing movement. Reducing this energy expenditure and/or improving the energy recovery can potentially improve locomotion efficiency and elicit a new sensation to a person who is walking or running. There have been previous efforts to include features in sole structures to help improve energy recovery at the metatarsophalangeal joint. However, known attempts in this regard have not addressed certain problems and/or have otherwise left substantial room for improvement.
In some embodiments, an article of footwear may include an upper, an outsole, and a spring plate. The spring plate may be positioned above at least a portion of the outsole. The spring plate may extend through at least medial forefoot and medial midfoot regions and may have an unloaded shape in which a front portion of the spring plate in the forefoot region is downwardly bent relative to a rear portion of the spring plate located rearward of the front portion. The spring plate may comprise an open region defined by a surrounding band.
In other words, they are developing or have developed a spring plate in the shoe to facilitate energy return. Here are some images from the patent:
Not to be outdone, a few days after the Nike press release Adidas came out with their announcement. A snippet in that announcement caught my eye:
“That attempt, according to the report, will be on a record-legal course and “is at least two years in development and has already yielded a prototype of a running shoe. The shoe is the key.”
The Adidas energy boost midsole has been shown to improve running economy, so the assumption is that their prototype shoe is along those lines.
Is any of this actually legal? The IAAF rules for this state:
The purpose of shoes for competition is to give protection and stability to the feet and a firm grip on the ground. Such shoes, however, must not be constructed so as to give an athlete any unfair additional assistance, including by the incorporation of any technology which will give the wearer any unfair advantage.
Are energy return shoes legal? As far as I know, no one has complained and no ruling has been made. No one seems to have a problem with the current energy return midsole materials, so it will be a matter of just how far that energy return concept is pushed before the IAAF think that rule is broken.
The key to a sub 2-hour marathon is not going to be the shoe. The key is going to be small incremental improvements in everything. The shoe is just one of those. That shoe will be tuned to the individual runner in terms of stiffness and energy return to opitmize their running economy via that energy return and minimizing muscle vibrations.