Nike.
For months, a roster of Nike All Conditions Gear trail runners has been making its mark across the world’s toughest mountain courses, climbing onto podiums while wearing a completely unannounced prototype footwear model. Every steep ascent, technical descent and tiring mile became a research lab at high altitude, feeding live trail insights back into the development process before the rest of us got a look in.
The athletes behind Nike’s All Conditions Racing Department testing include Lauren Gregory, Liam Meirow, Yao Miao, Riley Brady, Christian Allen, Cesare Maestri, Gabriela Lasalle and Takako Takamura, forming part of an international roster of 22 elite trail runners from eight countries. The department was created specifically to develop the next generation of ACG performance products alongside the people who will actually put them through their paces. “It felt less like testing a product and more like building something together,” says athlete Gregory of the experience.
Every race became another opportunity to adjust, refine and rethink the design, with athlete feedback helping shape what the prototype could eventually become. Nike has previously described the department’s development process as one that moves from the mountain to the Nike Sport Research Lab and back onto the dirt, creating a constant loop between real-world experience and product development.
Nike.
Nike.
Now Nike is pulling back the curtain on the ACG Kigerfly, honouring the athletes who helped take it from an unknown prototype to the race course, the runners who trusted something new before the world ever saw it became part of the development process itself. The process turned the Kigerfly from an experimental frame into a race-ready shoe shaped by athletes competing at the sharp end of trail running.“They [ACG Kigerfly] make running feel fun and have become the shoe I reach for. It’s taken me across countries and mountain ranges to podiums and victories,” says Meirow.
The department’s work extends beyond the Kigerfly, too. Nike launched the group in 2025 with 22 elite athletes, who have since contributed to projects including the ACG Ultrafly, which went through 13 rounds of testing and more than 30,000 miles, as well as Radical AirFlow, a technology developed to help athletes manage heat during races.
Nike.
The All Conditions Racing Department will continue racing in the Kigerfly, with more podium appearances expected around the world. Nike is also planning a deeper look at the shoe’s technology and development in early 2027, giving us a little longer to wonder exactly what has been hiding underneath all those race bibs.
Find out more here.
photography. courtesy of Nike
words. Gennaro Costanzo
