The idea for the shoe stemmed from a problem and question: "How can an athlete continue to train without succumbing to injury?"
This question spurred Nike to focus their efforts on creating a shoe with the potential to reduce running-related injuries. Nike recently unveiled its newest running shoe, the Nike React Infinity Run, billed to do exactly that.
Nike commissioned a study through the British Columbia Sports Medicine Research Foundation (BCSMRF) to test whether the combination of technologies deemed by Nike capable of lowering injury rate, really worked. This involved 226 runners who followed a 12-week variable training programme towards a half marathon. The study compared the Nike Air Zoom Structure (a traditional motion control shoe) and React Infinity Run Flyknit, a shoe which 'offers a more democratic solution to stability, and an advance from traditional motion-control designs.’
For the purpose of the study, Nike defined getting injured as “missing three consecutive workouts due to running-related pain”.
The theory: a stable, lightweight shoe with supreme cushioning
The Nike React Infinity Run is a Stability Soft shoe that provides plush cushioning with added stability, in an incredibly lightweight package. This model works well for runners needing more pronation control. Yet also works for the more stable runner looking for support during longer runs or when they are tired.
Featuring proprietary Nike React Foam
The React Infinity Run incorporates Nike's famous React technology: an energetic, super soft foam providing a lively sensation underfoot. For this model, Nike have added more foam (24%) at the forefoot and heel to provide extra cushioning.
The React foam is also known to be highly durable. It shows minor degradations in its cushioning properties even past 500+ miles, helping to keep you on the run.
A smooth and stable feel
The shoe has been designed with a wider base than previous versions to provide a more stable ride. The heel counter has been structured with a plastic clip going around the heel towards the side of the foot in order to guide the foot at each footstrike.
For a stable yet plush ride, the shape of the React midsole follows a rocker-geometry. This provides support for the 3 phases of a runner's stride: flexibility at toe-off, a smooth ride at mid-stance and cushioning at contact. This will create a more stable ride.
This version of the React Infinity Run features a Flyknit Loft upper, the all new version of Flyknit technology. As well as providing a sock like feel and a lightweight fit, the Flyknit Loft is also stronger and more durable than the previous iterations.
The above attributes result in a shoe that provides a reassuring feel. gently guiding the foot in a smooth, straight line, reducing side-to-side wobbling and movement, thus reducing the chance of injury.
The reality: putting the React Infinity Run Flyknit to the test
Straight out of the lab, Nike believed the React Infinity Run met the requirements to help reduce running-related injuries. The next step was to check its performance with real runners.
Nike wanted to analyse the performance of this new shoe against a classic motion control model. They chose the Structure 22 stability shoe.
For the purpose of the study, Nike provided the definition of injury as “missing three consecutive workouts due to running-related pain”.
Nike partnered with Dr Michael Ryan and the BCMRF to conduct a study with 226 runners who undertook a 12 week half marathon training plan. Half the participants wore the Structure 22 and the other half the new React Infinity Run.
The participants followed a variable training programme that involved mixing up the speed and the distance of the workouts.
At the end of the 12 week study, Nike looked at the difference in injury rate and pain perception between the two shoes. The results showed differences between the runners who wore the React Infinity Run and those who ran with the Structure 22.
The study found that 30.3% of the Structure 22 runners experienced an injury but only 14.5% of React Infinity Run runners experienced. Runners wearing the React Infinity Run shoes were 52% less likely to get injured than those wearing the Structure 22.
Is this the best running shoe to prevent injury?
Biomechanics is a fascinating and complicated field that continues to lead to the development of new understandings and new technologies. Running brands continue to conduct research to develop new shoes designed for specific purposes, The React Infinity Run is best suited 'to base-run days, those middle-mileage, moderate efforts’ and will help most runners reduce their risk of injury and stay on the run. That said, we are all unique and our training and lifestyle choices may still result in injury.
Most importantly, comfort is a very personal thing. No fitting system or review can substitute trying on running shoes for yourself. We advise runners to take the time to try a range of different brands and models, to see which suits them best.
It is worth noting that you will find similar technologies and design used by Nike in the React Infinity Run in other brands. Examples include, the Guide Rails support technology in Brooks running shoes and the rocker-geometry and the oversized midsole in Hoke One One running shoes.