The Robotic Revolution

This page is a preview based on early news and info and will be updated with a full hands-on review upon launch.

The global landscape of competitive road running is currently navigating a period of rapid technological acceleration, moving from "super shoes" into a tier that industry insiders are calling "hyper-shoes." At the absolute front of this pack is the Swiss brand On, with their Cloudboom Strike LS (LightSpray™).

This isn't just another racing shoe with a fancy plate; it is a fundamental departure from how shoes have been made for the last century. On has ditched the multi-component, labour-intensive assembly line in favour of a single robotic arm. The Cloudboom Strike LS is a proof-of-concept for a future where your shoes aren't stitched by hand, but "grown" by a robot in three minutes.

The LightSpray™ Paradigm: Robotics and Material Science

The defining feature here is the upper. Traditional high-end running uppers usually consist of 20 to 30 individual pieces—meshes, overlays, heel counters, and lacing reinforcements—all glued or stitched together. The LightSpray™ process collapses all of that into a single, automated step.

The "magic" happens at On Labs in Zurich, where a high-precision robotic arm extrudes a single, continuous filament of thermoplastic polyurethane (TPU) measuring roughly 1.5 kilometres in length. The robot sprays this filament in an engineered helix pattern directly onto a rotating "last" (a foot-shaped mould). As it sprays, the material fuses to itself and the midsole without a single drop of traditional glue.

The result? A seamless, one-piece upper that fits like a second skin. It’s breathable, elastic, and—crucially—eliminates the waste generated by cutting fabric rolls. This process alone achieves a 75% reduction in CO2 emissions compared to On's other premium racing uppers.

Technical Specifications: Cloudboom Strike LS (2026 Data)

Technical Attribute	Specification Detail
Weight (Men's Size 9)	~170g - 183g
Upper Weight	30g (Ultra-lightweight)
Heel Stack Height	39.5 mm (World Athletics Legal)
Forefoot Stack Height	35.5 mm
Heel-to-Toe Drop	4 mm
Upper Material	LightSpray™ TPU Monofilament (Laceless)
Midsole Foam	Dual-layer Helion™ HF (40% Bio-based Pebax)
Internal Plate	Spoon-shaped 100% Carbon Fibre Speedboard®
Retail Price (UK / USA)	£310 / $330

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Architectural Evolution: Echo 3 vs. Strike LS

To understand why the Strike LS is such a pivot, you have to look at the Cloudboom Echo 3. That shoe was often criticised for being a bit too firm and "traditional." It had a much higher drop (9.5 mm) and a lower stack height, which felt rigid compared to the "bouncy" offerings from Nike or Adidas.

The Cloudboom Strike LS addresses this by maxing out the stack height to just under the 40 mm limit allowed for legal competition. By shifting to a 4 mm drop, On has aligned this shoe with the modern racing trend that favours a forefoot-dominant landing. The integration of Helion™ HF foam—a supercritical Pebax-based material—provides an energy return of approximately 73.4% in the forefoot, placing it in the top tier of the 2026 market.

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The "Bounceboard" Innovation

On has also removed the traditional sockliner and "strobel" board (the fabric layer usually glued to the midsole). Instead, your foot rests directly on a "Bounceboard"—a thick layer of Helion HF foam sitting right on top of the carbon Speedboard®. This ensures you are in direct contact with the most energetic part of the shoe, maximising the "trampoline" effect during toe-off.

Reviewer Perspectives: The Good and the Bad

The reception for the Strike LS has been a mix of technological awe and "real-world" frustration. Here is the consensus from early 2026 testing:

The Good: Weightless Speed

• Non-existent Upper: At 170g, the shoe is lighter than almost anything else in its class. Testers describe the upper as "vanishing" on the foot, with zero hotspots or chafing because there are no seams or laces.

• Propulsive Feel: The combination of the Helion HF and the spoon-shaped carbon plate makes maintaining marathon pace feel significantly easier. One tester described the sensation as "Pepe Le Pew-like bounciness."

The Bad: The Barrier to Entry

• The Struggle is Real: Because there are no laces, the upper has to be incredibly snug to provide lockdown. Some testers reported spending 10 to 20 minutes just trying to squeeze their feet in. If you have high arches or wide feet, this might be a "no-go."

• Stability Issues: With a high stack and a narrow base, the Strike LS is notoriously "tipsy." It’s a dream for long, straight roads, but cornering or running on cambered roads can feel unstable.

• The Price Tag: At £310, it is one of the most expensive shoes on the market, sitting well above the elite racers from Nike or Adidas.

Design History: From Garden Hoses to Robotics

The origin of this shoe is pure "mad scientist" territory. On was founded by Olivier Bernhard, who famously glued pieces of garden hose to his soles to create the first prototypes. The LightSpray™ tech itself started as a student project by Johannes Voelchert, who was inspired by a video of a hot glue gun being used to make Halloween spiderwebs. He wondered if he could "grow" a shoe upper in the same way. Five years of development later, and that spiderweb idea is winning marathons.

2026 Roadmap and Insider Rumours

As we move through 2026, the big news is that LightSpray technology is expanding. While the Strike LS is the "halo" product, we expect to see this robotic manufacturing move into more consumer-friendly trainers.

Key 2026 Release Dates (Rumoured):

• March 2026: On Cloudmonster 3 Hyper LS — A LightSpray version of the popular max-cushion trainer.

• March 2026: On Cloudboom Strike 2 — An update to the standard (laced) racer.

• April 2026: On Cloudsoma — A brand new model designed for a "connected" trail feel.

The word from "The Running Event" trade shows is that the next generation of LightSpray (on the Cloudmonster 3 Hyper) will finally fix the "difficulty of entry" issue, using a more elastic filament that makes it much easier to actually put the shoe on.

The Cloudboom Strike LS is essentially a Formula 1 car for your feet. It is fast, expensive, and a little bit temperamental—but it represents the future of how we will all be running by the end of the decade.