I’ve had a mixed history with On’s running shoes. The design always pulls me in, they just look fast and flashy, and they tend to fit my feet really well, but it’s the ride that usually makes or breaks it for me.
The Cloudflow 5 is pitched as a fast training shoe with race-inspired geometry and On’s upgraded Helion™ HF supercritical foam. It’s meant to fill that tempo day slot in your rotation, sitting just under a race shoe in terms of performance.
I’ve been testing it during tempo workouts and fartlek sessions to see how it holds up when the pace picks up, and more importantly, how it handles when it doesn’t.
Here’s how it performs and whether it’s earned a spot in my rotation.
Key specifications
- Price: $180 at On.com / Sportsshoes.com (UK Readers)
- Weight: 9.5oz (269g) in US Men’s size 9
- Drop: 8mm (36mm heel / 28mm forefoot)
- Upper: Engineered woven mesh, light and breathable with an updated toebox
- Midsole: Helion™ HF supercritical foam with glass fiber-infused nylon-blend Speedboard
- Outsole: Road-ready rubber with mostly forefoot landing zones
- Extra attributes: Rocker geometry, good toe spring, and bold race-inspired design
Sizing and fit
The fit feels dialed in for medium-width feet. It's secure at the heel and midfoot with a nice spacious toe box, allowing for optimal toe splay, and as a result, performance.
The second set of eyelets help with fine-tuning ankle lockdown and midfoot support if you feel you need it; I used standard setup / eyelets as heel lock down feels good on my feet, but I like that On has introduced this, new to me, lacing design.
The tongue has good padding where it's needed and the collars and heel counter are all well padded and soft against your feet, in short, the upper conforms really well.
There's no wide option, though, so runners with broader feet might feel pinched.
Performance review
I’ve been testing the Cloudflow 5 during tempo sessions, fartlek runs, and structured workouts.
While it performs best during fast-paced efforts with strides landing you on your forefoot, the ride does feel pretty firm when the pace dips, or you attempt landing on your heels.
Alastair Dixon
At tempo pace or faster, the shoe flows reasonably well thanks to the aggressive toe spring (forefoot rocker), rockered midsole geometry, and that stiff nylon Speedboard plate.
It feels snappy and efficient when I’m pushing into threshold pace. The forefoot traction is excellent during landing, and toe-off, and the upper feels sleek and breathable.
The midsole foam, however, just doesn’t offer much in the way of rebound or energy return.
The Helion HF sounds promising on paper, but in practice, most of the propulsion is coming from the Speedboard, not the foam itself.
The foam layer (stack) underfoot is surprisingly thin, yes it looks beefy from the side, but that white section of foam is mostly sidewall wrap for stability and support, which is does a very good job of providing.
Just don't be fooled into thinking it's a high stack for a soft landing platform...
When I slow down to anything under tempo pace, the ride turns noticeably firm underfoot.
I run with a light footed stride so can handle a minimal shoe for the most part, but I think many runners will find this a little bit too firm, unless you're used to, and enjoy a ride like that.
Alastair Dixon
There’s also the sensation that I’m not getting much help from the foam even when I am running fast.
It feels more like a mechanical push coming from the compression of the holes / pods in the midsole rather than a responsive bounce back from the foam compound itself.
The shoe’s weight of 9.5oz is a little heavy when compared to other tempo running shoe options on the market that I rate highly right now, like the Endorphin Speed 5, and Mach 6, for example.
I’m starting to feel a pattern with On’s midsole tech; firm foam, lots of structure, but not much natural energy return. Helion just isn’t delivering like other modern foams right now, and that’s holding the shoe back.
Traction is great but there are areas of exposed foam on the outsole which will wear down faster than the rubber over time.
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My verdict
The Cloudflow 5 is a great looking shoe that performs decently at tempo pace, but it’s limited by a firm ride with a low foam response (the plate certainly propels you forward) that doesn’t translate well into slower efforts.
If your rotation needs a dedicated threshold or progression-run shoe and you don’t mind a firmer feel, it can serve a role in your rotation for sure but it’s not a versatile daily trainer, and it’s definitely not for recovery runs.
The upper, outsole traction, and overall design are excellent. But at $180, I expect a lighter shoe, and a bit more comfort and bounce from the midsole foam.
