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As you lay out your Get in Gear race kit, have you paused to think about what is going on your feet? Maybe you are lacing up a pair of super shoes for the first time and wondering if they will help you run faster. Maybe you are debating whether you should invest in super shoes or worried they might contribute to injury. And maybe you are reading this thinking “What's a super shoe?”
What Are Super Shoes?
“Super shoes” is the sassy name for a type of performance running shoe that was first introduced in 2016 by Nike, although all major shoe companies now have their own version. The shoes are characterized by a stiff curved carbon fiber plate embedded between 2 layers of lightweight compliant and resilient foam.
The nickname “super” comes from the improvements in running economy—the effort required to hold a given pace—demonstrated by those wearing the shoes. A preliminary study done by Nike on a group of high-performance runners found an average improvement in running economy of 4% in the special shoes. These shoes earned the moniker Nike Vaporfly 4%.
What makes the shoes so speedy is still up for debate—certainly the light weight helps. The compliance of the foam allows the shoe to better absorb energy and the resilience helps return that energy to the runner. The stiffness of the plate may help propel the runner forward with less work being done by the calf muscles. The resulting increase in running efficiency may well be a combination of all these factors working together.
Do Super Shoes Make You Faster?
For elite runners the answer is an unequivocal yes. Since 2016, all world records from 5 km to the marathon have fallen to runners wearing some version of the shoes. The average 4% improvement in running economy has led to roughly 2% improvement in race times. Not everyone responds equally to the shoes, however, with the improvements in running economy in the original Nike study ranging from a minimal response of 1.6% to a “super responder” who saw a bump of 6.5%. Runners can respond better to the super shoes from a particular brand, which has even caused some athletes to switch sponsors so they can race in their preferred shoe.
More recent studies have examined the effect of super shoes on the running economy of recreational runners. One study with subjects running at average paces of 6:34 to 8:47 minutes per mile replicated the 4% average improvement seen in elite runners, while also finding a large range in responses (1.8 – 7.7 %). A more recent study, however, found that at an 8:03 minute per mile pace, runners were only 1.6% more economical. This decreased to a 0.9% average improvement for runners at a 9:40 pace with some runners even less economical in the super shoes than in their regular trainers.
Why the potential different response between elite and recreational runners?
The combination of the lightweight compliant resilient foam and stiff carbon fiber plate has been likened to a spring that is tuned to the mass and velocity of elite runners. The further you get away from that mass and velocity, probably the less beneficial the shoes are at improving your running economy. Vertical ground reaction forces are greater at higher speed, so even though elite runners have smaller mass, they are likely causing greater compression and energy absorption in the compliant foam. This energy is then returned to the runner. Slower runners may not deform the form in the same way and thus do not get the same energy return. The faster speeds may also interact with the stiffness of the carbon fiber plate in a way that is not well understood. The next generation of super shoes is likely to include models designed for slower and heavier runners and in fact Salomon just released a shoe for 3:30+ marathoners.
What are the Risks / Downsides of Running in Super Shoes?
The shoes typically cost north of $250 and the lightweight foam is not as durable as your daily trainer, so will not last as many miles. Research has shown that runners change their running mechanics in the shoes—often in the direction of longer strides, a lower cadence and more time on the ground, while also changing the energy demands around the foot and ankle. The shoes are new enough that these changes haven’t been well-studied in terms of injury risk, but there have been case reports published on runners sustaining bone stress injuries in the foot while using the shoes.
Should I invest in Super Shoes?
If you are a newer runner, you may be just as well-served in a lighter weight cushioned trainer. If you are interested in getting faster—simply running more miles will improve your running economy. Focused speed work and strength training can also be hugely beneficial.
For a more experienced runner looking for an edge in race performance, yes super shoes may be a worthy investment. Even though the bump in running economy may be less in non-elites, there is some evidence of super shoes helping to decrease muscle damage in long events such as the marathon, which may make the actual performance gains greater in recreational runners. Make sure to find a pair that fits your foot well and feels comfortable. Allow for a gradual adaptation period, especially if you are injury prone. If you know a certain shoe brand fits you well, that company’s super shoe may be a good place to start. The shoes can feel very fast and bouncy, which can boost mental confidence and also aide performance.
What ever shoes you choose to wear for Get in Gear, enjoy the day and have a great race!
This article originally appeared in the The Connection, TCM's weekly e-newsletter. Subscribe here.
Kristen Gerlach, PT, PhD, is a physical therapist who specializes in working with runners. She is one of the team of Motion Experts TCM has gathered to help its subscribers and participants get the most out of their running. Have a question for Kristen: [email protected] or website: instridemnpt.com.