By Brian Metzler

No matter how you slice it, On Running has come a long way in the past several years. Since its inception in 2010, the Swiss brand has always focused on three things that have set it apart: innovative midsole cushioning, a clean, almost postmodern aesthetic, and, of course, running performance. The first two were relatively easy to come by as it turned heads with its unique formulations of its original tubular CloudTec cushioning systems and its avant garde upper designs. But moving the needle on running performance was a little bit more difficult, if only because several other brands began taking shoe technology leaps and bounds since 2017 with carbon-fiber propulsion plates and next-generation midsole foams.

On began making advanced race-day shoes in 2018 and eventually refined the carbon-plated Cloudboom Echo into a proper marathon racing shoe. (U.S. Olympian Jake Riley wore a version of the Cloudboom Echo in the Tokyo Olympic marathon in 2021.) On’s continued push for innovation could be seen on the feet of Hellen Obiri as she won the Boston Marathon in 2023 wearing a pair of On CloudTri prototype shoes and won it again this year wearing a pair of Cloudboom Strike LS prototypes with a snug-fitting, 3D-printed laceless upper and collar. Both shoes were approved by World Athletics (which limits shoes to a 40mm max stack height with a singular propulsion plate) but neither has been released to the public. 

Obiri will wear an updated version of the revolutionary shoe she wore in Boston this year while running the Olympic marathon on August 11 in Paris. On is expected to officially unveil that shoe on July 15 (likely with a very high price tag and very limited availability), but in the meantime, it is releasing the Cloudboom Strike today (July 5) as a high-end racing super shoe engineered for a wide range of distances. I’ve been running in a wear-test sample of the Cloudboom Strike for the past month, and my initial takeaways are that it’s an interesting, versatile and very high-performing shoe. As much as I’m eager to test out the forthcoming Obiri pro model, I’m pretty content with having the Cloudboom Strike in my quiver for the rest of the summer.

What’s New: The Cloudboom Strike is a brand new maximally cushioned road racing super shoe built around an innovative new construction. The carbon-fiber propulsion plate is embedded into the bottom outsole/midsole chassis, while a thick removable interior Helium Hyperfoam foam midsole layer offers complementary cushy responsiveness from a firm interior “bounceboard.” That unique two-part construction maximizes the stack height of the Helium Hyperfoam layer and allows it to deliver optimal energy return and efficiency while still keeping the shoe within the regulatory framework of the World Athletic specs for elite runners. (The fact that it has a removable midsole is irrelevant; what’s important is that it’s independent of the chassis.) The upper is a very breathable one-piece, semi-transparent mesh with a molded heel and integrated tongue that provides comfort and fit in targeted anatomical zones, while minimal outsole rubber segments keep the shoe as light as possible with sufficient traction.

Fit/Feel/Ride: The Cloudboom Strike fits true to size with a medium/narrow interior volume and ample wiggle room in the forefoot for toes to wiggle. The step-in sensation feels soft, bouncy, and comfortable, but also appropriately sparse—with minimal padding around the heel cup and in the tongue. It has flat, premium-quality laces that really do a good job of locking the foot in place with the featherweight and subtly reinforced upper. The secure, locked-down fit, combined with the innovative design of the chassis and the removable/drop-in midsole, paves the way for such an exceptionally smooth, resilient and high-performance ride. 

The Cloudboom Strike feels soft and accommodating at the heel-strike phase of a stride (and a tiny bit wobbly, too, at slower paces) but it also quickly and easily transitions into the mid-stance phase and sets up a lively jolt through through the  toe-off phase. The sensation of the ride is springy but not excessively bouncy, more smooth and rolling but not overly energetic. The faster I ran, the more stable and fluid I felt, but running at slower paces didn’t feel bad. (On says it engineered a decoupled effect to each of the midsole platforms which allows independent deformation, and increased loading and release.)

Why It’s Great: It’s a high-stack, maximally cushioned shoe that provides optimal cushioning and energy return. On’s unique two-part midsole design feels exceptionally soft and vibrant underfoot even though both the drop-in/removable midsole and the chassis are extremely firm and inflexible. That gives it both long-haul comfort but also short-distance snappiness, which is uncommon for most racing super shoes. It has a high-off-the-ground feel to it, and that takes some effort to harness for 5K pace, but once you rev up to that speed, it’s easy to maintain it with the profound rolling sensation it produces. Running post-run strides took some effort but less-intense workouts did not. I ran a progressive 3 x 600 workout with each one slightly faster than the previous one and probably could have added a fourth one. 

Specs

Weights: 5.9 oz. (women’s 8), 7.4 oz. (men’s 9)

Heel-Toe Offset: 4mm; 39.5mm (heel), 35.5mm (forefoot)

Why You’ll Love It: You’ll love it because it’s comfortable and smooth, it’s very responsive, and it offers a wide range of pace versatility. It has all the indications that it can be a top-tier race day shoe for faster runners (sub-6-minute pace or a ~2:37 marathon), but the shape and smooth transition from heel to forefoot also make it conducive for running at 8-minute pace (~3:30 marathon) or 9-minute pace (~3:55 marathon). For that reason, it’s one of only a handful of carbon-plated super shoes that I’d wear for long runs (I have so far run 10+ miles twice) and speedier workouts (along with the Brooks Hyperion Elite 4 and the Saucony Endorphin Pro 4).

Pro: It’s light, fast and fun, without any excessive or extra material to make it heavier than it needs to be.

Con: Although the lightweight laces are exceptional, they’re also exceptionally long. It could be that my wear-test model came out of an early batch of shoes with irregularly sized laces, but the laces were so long that I initially tucked them under the matrix of my laces to keep them from swatting my ankles and then I eventually cut about 5 inches off. The only other complaint is that the longitudinal channel that runs from heel to toe through the center of the bottom of the shoe can occasionally collect pebbles. But if you’ve run in On shoes through the years, you know that’s now part of its legacy.