Expensive running shoes don't prevent injuries, but comfortable ones might
Despite the lack of proof, we’re bombarded by claims from global footwear companies about the advantages of their pricey products
If you have ever suffered an injury from running, you are not alone. About half of all adults who run regularly will get injured each year. And those who have been injured have a higher risk of being injured again.
So it's no surprise that avoiding injuries is a priority for runners, one third of whom are willing to upgrade their footwear if they feel it is safer and will improve their performance. But do the promises made by global footwear companies about their expensive running shoes stack up?
A recent study, based on 134,867 reviews of 391 pairs of running shoes from 24 brands, found that inexpensive running shoes received a better rating than expensive ones. The 10 most expensive pairs of running shoes (average price US$181) rated 8.1 per cent worse than the 10 cheapest pairs (average price US$61), says Jens Jakob Andersen, the Danish founder and CEO of RunRepeat.com which conducted the study.
"People buy running shoes that are three times more expensive but are less satisfied," says Andersen. "We did this study to spread the word that 'the higher the list price, the more value' does not apply to running shoes."
In August, the Hong Kong Consumer Council echoed a similar alert in its publication Choice, quoting results from a study by the International Consumer Research and Testing and German consumer organisation Stiftung Warentest of 15 running shoes from nine brands. The shoe prices ranged from about HK$700 to HK$1,220.
Twenty-four experienced runners evaluated the shoes on performance, comfort level and preference. Four of the models rated highest (four out of five points) by the runners belonged to the low-to-mid-price range (HK$780 to HK$900). On the other hand, the ratings for the most expensive models were just average.
But does the modern running shoe's extra safety features, such as increased stability or extra cushioning, really protect people from injury?
So far, studies have proved inconclusive. One study that randomly allocated 81 female runners to shoes with different levels of stability based on their foot posture (pronated, neutral, supinated) found no difference in injury rates during a 13-week training programme. Another, which randomly allocated hard- or soft-soled shoes to 247 runners, also found no difference in injury rates over a five-month period.
But despite this lack of proof, we're bombarded by claims from global footwear companies about the advantages of their expensive products. These claims, are often full of vague terms, that vacillate between the medical and sportswear industries.
Words such as "zoom", "fast", "elite" and "launch pad" are used among others suggesting direct benefits from shoes, such as "better" and "safer". Footwear companies also use terms once synonymous with luxury cars by claiming their products offer the most "fluid", "smooth" or "plush" experience for runners.
The problem is compounded by companies using "surrogate outcomes" to support claims that their newest technology may reduce risk of a running-related injury.
If we want to test whether a new footwear model, or piece of footwear technology, actually protects against injury, we'd measure - in a controlled study - how many people get injured wearing (and not wearing) the product. But tracking who does and doesn't get injured over an extended period is time-consuming and expensive.
To circumvent this, we could instead measure what effect the shoes have on outcomes that may relate to increasing the risk of injury. We may, for example, measure how much they reduce your foot from rolling (pronating) or soften your impact with the ground (ground reaction forces) as "surrogates" for measuring injury.
But these aren't strong surrogates because neither foot pronation nor high ground reaction forces are strong risk factors for running-related injuries.
In the search to gain an advantage in an increasingly competitive marketplace, footwear companies are forever pushing the boundaries with their claims. And when they slip up, the results can be disastrous.
In 2012, a class-action lawsuit was made against Vibram USA, the company that makes the FiveFingers running shoes, the glove-like footwear at the epicentre of the "natural" or "barefoot" running phenomenon.
The case was based on unsupported and deceptive claims of "strengthened foot and leg muscles", "reduced risk of injury" and improved "balance and agility" and "spinal posture" from wearing the shoes. Vibram USA settled, offering refunds to customers and discontinuing the use of these claims.
Similarly, promises of more toned buttocks from walking in Reebok's EasyTone shoes were found to be deceptive and misleading by the US Federal Trade Commission.
Reebok was required to pay US$25 million in customer refunds and banned from making unsubstantiated health and fitness claims relating to its "toning" footwear.
Selecting running shoes based on the purported benefits of certain foot protective features, such as "cushioning" and "motion control", offers no protection against running-related injuries.
In fact, we may have reached a point at which running shoes are being over-engineered to satisfy market trends, rather than being designed to make running safer.
Interestingly, the solution to selecting a shoe may be as simple as how comfortable they feel. Although footwear comfort is difficult to define and quantify, most people can sense whether the shoes they're trying on are comfortable or not. Support, fit and foot alignment are among factors that influence feeling comfortable in a pair of shoes.
Comfortable running shoes are associated with lower frequency of injuries than uncomfortable shoes. This suggests your body may be the best judge of footwear that's ideal for you.
The next time you feel bamboozled by the cornucopia of gels, foams and rubbers in running shoes, arm yourself with the knowledge that comfort is one of the best determinants of whether a pair of shoes is right for you, and what may work best for preventing injuries are your wallet and your peace of mind.
John Arnold is a lecturer in exercise science at the University of South Australia.
Additional reporting by Jeanette Wang