Development of GX SONIC 6 racing swimsuit for greater lightweight feel in water

Competitive swimmers never stop wanting to go faster, and at Mizuno, we have developed our flagship GX SONIC series of racing swimsuits to match the passion of those athletes. Seeking to further enhance its leading-edge series and provide athletes with a competitive advantage, we worked on development from both fabric and design perspectives. The result was the latest evolution: the GX SONIC 6.

1.Focusing development based on athlete and front-line staff feedback

We pinpointed the areas for development based on thorough interviews with brand ambassador athletes and front-line staff who support them most closely.Through that process, we received specific feedback such as that recently more swimmers are choosing suits which prioritize ease of movement over strong support, and that female athletes prefer models with soft shoulder straps which make shoulder blade movement easy. Learnings such as these were incorporated into the focal points of fabric development and product design.
Swimsuit fabric development demands completely different functionality and features to typical garments. In particular, we concentrated on four key aspects: fabric surface frictional resistance, water resistance (surface water repellency and lightweight feel in water, fabric durability (strength and stretchiness), and adhesive properties (compatibility between the swimsuit and the adhesive agent). The three focal aspects of product design and development were the feeling of comfort such as comfortable tightness and length, preventing water from entering between the body and swimsuit upon starting, and fashioning shoulder straps for women’s models which make shoulder blade movement easy.

2.Fabric development in collaboration with Toray, a Japanese textile company

Fabric development involved using a novel thread structure - suggested by Toray - featuring special slits. The development program succeeded in creating swimsuit fabric with even greater water resistance than previous models, while also providing a lightweight feel in water by preventing water entering the thread and fabric. This new fabric not only features enhanced surface water repellency performance, but also up to 6.2% lighter swimsuit weight in water compared to previous models.^*1

*1 GX SONIC V ST and GX SONIC 6 NV half spats for men

3. Design and development through co-creation with Mizuno brand ambassadors

Design and development focused on the comfortable feeling of fit for women’s swimsuits in particular. During development of the straps, we created a concept of enveloping a broad elastomer mesh string with soft-feeling fabric, independent from the neckline and underarm area. This advancement eliminates the unevenness in previous models’ straps, and as well as feeling more comfortable on the skin has improved stretchiness and places less stress on the shoulders. In addition to the shoulder parts, the overall product design has been renewed, with the straps now forming a V shape when seen from the back. This advancement means that the straps no longer press down on the shoulder blades.
Fabric stretch and patterns were repeatedly revised based on feedback from brand ambassador athletes testing prototype models, ultimately achieving both strap softness and comfortable feeling of fit.
The men’s swimsuits benefited from suggestions from Professor Yusuke Takahashi of Chuo University about the concept and design, as well as extensive evaluation of prototypes by the University’s competitive swimmers.

4.Planned to be worn at the tournament from July 2024

The GX SONIC 6 went on sale in September 2023, and was worn by a total of 379 athletes at the Japanese swimming trials held in March 2024. Among them, Rikako Ikee, Reona Aoki, Ippei Watanabe, and Yu Hanaguruma qualified for the national team while wearing GX SONIC 6. This model is also planned to be worn at the tournament held from July 2024.

We aim to continue developing products by valuing the inputs of athletes and front-line staff, supporting sporting activities by offering better sporting goods.