On has updated its marathon racing franchise with a new cushioning architecture called CloudTec Sphere and a midsole foam 15% lighter than the previous version. Six athletes have set personal bests in the shoe ahead of its July 30 launch.
On is targeting the closing miles of a marathon, where races are often decided, with a shoe it says can make the difference.
The Swiss running brand has unveiled the second generation of its Cloudboom marathon franchise, the Cloudboom Strike 2 and LightSpray Cloudboom Strike 2, with a redesigned cushioning architecture and a midsole foam 15 percent lighter than the previous version.
What’s new in the cushioning
The main update is CloudTec Sphere, a new iteration of On’s proprietary CloudTec cushioning system. The geometry features precision-engineered channels designed to improve impact absorption and energy return, especially late in a race. It is paired with a new Helion HF midsole, 15 percent lighter than its predecessor, and a curved carbon Speedboard sandwiched between layers of dual-density foam.
Personal bests as proof of concept
On has led the rollout with athlete performance results. Six of the brand’s athletes have set personal bests wearing the shoe. Hellen Obiri improved her marathon time by 1 minute 48 seconds in London; Yeman Crippa won in Paris with a 48-second improvement; Joe Klecker cut his personal best by 4 minutes 41 seconds in Boston.
The results serve a commercial purpose as much as an editorial one. On is competing directly with Nike’s Vaporfly and Alphafly lines and adidas’ Adizero franchise for credibility in elite long-distance racing, a segment where podium appearances have become a primary marketing asset.
The technology behind LightSpray
The flagship LightSpray Cloudboom Strike 2 is built around a shortcut in upper manufacturing. Rather than stitching and laminating dozens of components across a long, multi-factory workflow that can run to roughly 200 steps, On uses a fully automated cell in which a robotic arm sprays a continuous thermoplastic polyurethane filament onto a mold, forming a seamless, laceless, one-piece upper in about three minutes.
Each shoe uses roughly 1.5 kilometers of filament, and because every robot follows a programmed, repeatable path, the process can be replicated precisely across sites. According to a study by the University of Cape Town, the combined setup delivers a 1.6 percent improvement in running economy against leading industry benchmarks.
That repeatability is what has let On scale the concept from its first Zurich pilot line, with four robots, to its Busan plant, with 32, and toward a wider network of nearshore factories. The logic behind that expansion - speed, consistency, and less dependence on labor-heavy assembly in Southeast Asia - also functions as a hedge against tariff exposure and broader supply chain disruption.
Pricing and availability
The Cloudboom Strike 2 weighs 191 grams and is priced at $250/€250/£230. The LightSpray version weighs 158 grams and retails at $310/€320/£300, including the Elite Run Sock High Hyper. Both shoes launch July 30.
