The modern running shoe is 40 years old and can now form part of a body area network comprising sensors, feedback monitors and on-road entertainment. But is it worth the extra cost?
This year, the modern cushioned running shoe celebrates its 40th birthday. The successor to the plimsoll, trusty companion of those romantic or absurd athletes of 'Chariots of Fire', this now almost ubiquitous footwear has spiralled in cost with each development in culture, material, electronics, sensors and personal area networks. Today, you can run with your pace, location, heart monitor and even your music all working together to enhance your performance on the road. But is the cost worth it to add to the performance advantage for most runners?
Running as a sport became popular in the 18th century – an era of innovation in all walks of life – and brought about the development of a lightweight shoe that could grip the ground with a leather upper and a wooden grooved sole. Plimsolls soon followed in the 1830s when the wooden soles made way for rubber. Spikes were not far behind, invented by Joseph William Foster, the founder of Reebok, in 1852.
The next big development was vulcanisation, allowing canvas shoes to be melded with rubber soles which revolutionised shoe manufacturing in the early 20th century. Adolf Dassler (founder of Adidas) differentiated between long-distance runners and sprinters for the first time in the 1920s and his shoes were the favourite of Olympians for decades to come.
Innovation in footwear
Phil Knight, a business major at the University of Oregon and a miler on the track team, started to develop the first cushion heel wedge designed by Bowerman in 1972. The company, originally called Blue Ribbon Sports, became known as Nike more than a decade later. This was the first modern running shoe.
Throughout the 1970s, demand for the specialised shoe showed that consumers were ready for further innovation in footwear. Frank Rudy from Nasa introduced the idea of bags filled with pressurised gas that compress under impact to Nike. The bags absorb shock and cushion the foot. The cushions were placed in the soles of Nike shoes and are still used 20 years later.
During the 1970s running shoe designs were based not only on the type of running the person did, but the running style the runner adopted. The three running styles that shoes were designed for included neutral runners, supernation runners and pronation runners.
The final advancement that running shoes received during the 1970s was the use of ethylene vinyl acetate (EVA). This material added an air cushion to the design, providing runners with extra cushion and shock absorption when they ran.
Throughout the 1980s and 1990s, these technologies filtered down to ordinary stores. But trainers in general were becoming more of a fashion statement as a result of endorsement of highly paid sports stars and their importance in the emerging rap scene.
A growing industry
Today's shoes feature all manner of technologies including electronics and sensors, everything to keep consumers believing that the '20bn running shoe industry will help us cushion every stride. But in recent years there have been claims that injury rates for runners are actually on the rise, that everything we've been told about running shoes is wrong – and that it might even be better to go barefoot.
Some suggest that, despite all the technology, the true cost of running is injury. Dr Daniel Lieberman, professor of biological anthropology at Harvard University, has been studying the growing injury crisis in the developed world for some time and has come up with a conclusion that modern cushioned running shoes make our feet and knees weak, which causes injury.
In a landmark study published in Nature in 2009, he concluded that: "Modern running shoes may be dangerous because they promote a heel foot strike, which this study concludes produces far greater impact than landing on the forefoot. Combined with greater proprioception or 'feel of the ground' by running barefoot and stronger foot muscles."
Lieberman also believes that if modern trainers never existed more people would be running. And if more people ran, fewer would be suffering from heart disease, hypertension, blocked arteries, diabetes, and most other deadly ailments of the western world.
Lieberman's study has influenced manufacturers, many of whom have created simpler but often more expensive solutions to promote forefoot strike strides. This has culminated in the eye-wateringly expensive Ecco BIOM shoe.
Since most running shoes only last about three months before the midsole – the part which offers the cushioning – gives way, the bill for multiple replacements of this shoe will soon stack up, with each pair costing £180.
Personal Area Networks
Consumer electronics companies have muscled in on this lucrative industry. In 2007, Nike introduced the Nike+ app, which was bundled with the iPod Nano, the Touch and the iPhone. Nike also introduced a piezo-electric shoe pod that would measure pace and distance and transmit this data directly to the iPod via the app.
Since then, Nike has added a separate wrist band, a heart rate monitor in collaboration with Polar, and a GPS watch in partnership with TomTom.
Other companies also have their version of the personal area network. Motorola has its MotoActv device, which combines a media player, stopwatch, GPS tracker and pace tracker in a single device but can link to a standard Bluetooth or ANT+ heart rate monitor.
"Runners want a bespoke device that does everything. They don't want to spend valuable time putting on separate devices such as shoe pods, media players and sports watches," says Craig Nicholas, portfolio and marketing director of Motorola.
Micoach, developed by Adidas, works in a three-part system with a stride sensor, a heart monitor and a receiver. The receiver coaches you based upon the data being collected from the stride sensor and heart monitor. The receiver will tell you to either speed up or slow down based upon your heart rate, inform you the data has been collected, and will let you know how far into your workout you are and how much is left, as well as playing your music.
Both the Micoach and the MotoActv devices depend largely on triaxial accelerometer technology. This is increasingly being incorporated into smartphone devices – making it possible to develop apps to take advantage of them. An accelerometer measures acceleration relative to freefall and thus makes it ideal to calculate pace and energy, according to Steven Dean from Freescale Electronics.
"I see reasonable growth in the pedometry market in running and fitness," he says. Freescale Electronics are leaders in the development of accelerometers, which are used in a variety of devices. The sensors themselves cost about $1.15 compared to the pennies that older piezo-electric sensors cost, but in terms of accuracy they are miles better, claims Dean.
Accelerometer versus GPS
However, none of the systems out there can cross-pollinate data to improve accuracy. Both accelerometer- and GPS-based pace and distance measuring devices have their advantages and disadvantages. GPS is a line-of-sight technology and can fail if you run under a bridge, for example. It is also very power-hungry. Accelerometer technology obviously cannot track a route and display that map for you afterwards.
For these systems to communicate a wireless standard is required, and two have emerged. The ANT+ interoperable ecosystem offers an install base of more than 11 million devices that monitor heart rate, weight, speed and distance, for example. With nearly three billion Bluetooth-enabled endpoint devices such as PCs, tablets or smartphones on the market, direct communication with Bluetooth becomes the optimal wireless communication channel.
The trend of using wireless monitors and sensors to enhance physical activity is sweeping the fitness and running communities. Wireless technologies such as ANT+ and Bluetooth could be the front-runners for devices including consumer heart-rate monitors, speed, distance and cadence sensors, and foot pods.
For a long time, ANT was the key wireless technology in sports and fitness. Since the conception of Bluetooth low energy, the industry has questioned whether ANT will still lead the field. Backers of its rival contend that standards always win. Yet there are talks of incorporating ANT in multichip protocols. For integrated circuit suppliers, the question is whether the benefits of adding ANT outweigh the cost of a combination development. The odds seem stacked against it.
Bluetooth 4.0 technology is making inroads into a slew of fitness and health products, and consumers can expect the trend to only get hotter. The Bluetooth Special Interest Group has recently formed a new Sports and Fitness Working Group, which aims to increase interoperability between wearable gadgets and sensors and so-called 'hub' devices such as smartphones, televisions and gym equipment.
According to a press release, IMS Research forecasts more than 60 million Bluetooth-enabled sports, fitness and health monitoring devices will ship between 2010 and 2015, most of which will be heart monitors (17.7 million), sports watches (7 million), and speed and distance monitors (2 million).
Aidan McKinnon is a sports physiotherapist and coach who works with several Olympic hopefuls for Team GB's athletics team. He is also a fitness advisor to the British Army and a former soldier. He points out that all these technology improvements produce only "minor marginal improvements" in performance.
"Armies have to walk and run over large distances in boots designed for longevity, stability and sturdiness. The weight and cushioning of a shoe means very little when you're heaving heavy body armour and back packs."
However, McKinnon points out that elite athletes are the only ones likely to benefit from the marginal improvements in the latest running shoe tech.
"Most people need a shoe that lasts. The running shoe industry is geared at the sport of running and not the pastime of running."
However, he believes that the latest electronics can help mainstream runners.
"We use a great deal of motion tracking and gait analysis when we train our athletes. These can definitely help runners of all abilities. Knowing where you are and where you want to be is very important to know how you are doing to achieve personal goals."
But electronics are still an extra cost. Motorola's MotoActv will typically set you back about '250, while the Nike+ GPS Watch will cost around '180. Heart rate monitors, shoe pods and other devices add to the growing shopping bill.
Those running the London Marathon can easily clock up hundreds of miles in a few weeks. Therefore, the suggestion that running is an easily accessible pastime and is far cheaper than joining a gym has to be questioned.