Pursuing the fastest speed scientifically—The new “SMOOTH SPEED ASSIST” function resulting from co-creation within the company

Long-distance track and field events such as marathons and long-distance relay races have entered a new era with the emergence of thick-soled shoes in recent years. Based on various studies and numerous discussions, Mizuno concluded that the midfoot strike and forefoot strike are efficient landing methods for running quickly. Naturally, it is difficult to maintain an efficient landing method from start to finish. In view of that, we carried out repeated trial-and-error processes and conducted many interviews with athletes to create a new function, “SMOOTH SPEED ASSIST,”* which strikes a balance between the conflicting elements of “running efficiency” and “reducing burden.”

*The “negative action of the ankle plantar flexion torque,” which is a general indicator of the eccentric contraction of the triceps surae muscle, was measured in experiments on external subjects. The “negative action of the ankle plantar flexion torque” of products equipped with the SMOOTH SPEED ASSIST function was compared with our own products not equipped with the same function, when running at a racing pace (16 - 20km/h), and we confirmed that the value was lower for products equipped with the function.
*Effectiveness and sensation may differ among individuals.

The most important feature of SMOOTH SPEED ASSIST is the cut heel section. This cut reduces the burden on the muscles and tendons around the calves, and at the same time, supports natural forefoot and midfoot landing. In developing this new function, the development team took inspiration from the running spikes used for short distances. Their idea was sparked by their discovery of the similarities between the ideal step pattern for long-distance races, and the step pattern for short-distance races.

The SMOOTH SPEED ASSIST is a new function created by bringing together various ideas from every expert in Mizuno and rethinking what smoothness in speed-running actually means. The presence of co-creation among various in-house experts is what lies at the heart of its birth.

Co-creation 1)  Co-creation between designers and those in charge of theory-building

Even if the designers were able to reflect the feedback arising from the prototype and the physical experience of that back into the manufacturing process, they could not develop a theory and were subsequently unable to develop the process from a single case of product design. However, such “theorizing” activities were accelerated through co-creation with other members within the company who are skilled in biomechanisms. As a result, the relationship between the physical experience and the actual phenomena was clarified, making it possible to roll out SMOOTH SPEED ASSIST to multiple models.

Co-creation 2)  Co-creation with successive generations of designers

In the abovementioned process of developing a theory, interviews were conducted with successive generations of track shoes designers and craftsmen. By doing so, the designers learnt that the design concepts that they had arrived at by eliminating stereotypes and pursuing the vision of “helping people run faster,” shared commonalities with the design concepts that Mizuno had always focused on in its product development for other track and field races. Hence, they were able to elevate and enhance the function by incorporating past knowledge, know-how, and experience.

Co-creation 3)  Co-creation between designers and those in charge of work in the field

Mizuno has continued to create new functions in its pursuit of the vision of helping people to run faster. However, to incorporate a function into products that are supported by the market, it is vital to understand the market and obtain opinions from those in the field. To that end, the designers visited the actual field numerous times together with the personnel in charge of marketing and sales. They clarified the design points that demonstrate the functionality based on the analysis of feedback from the field, and this process contributed to improving design precision and to the creation of product variations corresponding to different uses.

The new SMOOTH SPEED ASSIST function is the result of various forms of co-creation within the company. In the future, we plan to optimize the function for various distances and create an extensive line-up of shoes equipped with the SMOOTH SPEED ASSIST function.