On have delivered a lot of models of shoe over the last few years, from comfortable workhorse road shoes for training miles to trail shoes to carbon-infused race shoes. But their newest innovation is a trail shoe designed for big miles – the Cloudultra.
We have featured many of the On range on RUN247.com here.
At first glance the Cloudultra does have a lot in common with the Cloudstratus, with its distinctive double layer of clouds to deliver extra cushioning and support and the 8mm drop. But the Cloudstratus is designed for road and the Cloudultra for trail, so it has a much grippier sole. It also feels more pared back than the Cloudstratus without the padded tongue and the padding round the ankle. Instead it has an integrated tongue which I found really comfortable and niggle-free as it doesn’t shift around.

It is a very comfortable shoe from the off. You definitely feel the cushioning in the sole and the upper is really nice and light with no rubbing. I found it quite a fitted shoe, so your foot doesn’t slide around, but the mesh upper is very flexible, giving your foot plenty of opportunity to move. And of course if your foot does swell a bit during a very long run there’s the new ‘Flip Release’ system, which is essentially a clip on the laces, which will instantly give you a bit more slack.
On the run you really feel the substantial cushioning, but it isn’t a squishy sort of cushioning; the clouds make the shoe very responsive. You also benefit from the ergonomic rolling motion common to On shoes. However, if you run on a bit of road you can find that the cushioning from the Helion foam is quite firm. This is presumably going to be a good thing for durability, or if you’re a heavier runner, but it might not be everybody’s cup of tea if you’re used to a more slipper-like sort of cushioning.

I found them a great shoe for hard trails. While the foam felt a bit firm for me on the road, it definitely came into its own on the trail. They’re great on rocky paths, giving your foot plenty of protection on the sole and with the toe bumper. They’re a total joy on the downhill, giving you loads of cushioning and the slightly snug fit means that your foot doesn’t shift around. The quality of the build of On shoes is never in any doubt and every element of the Cloudultra oozes quality.

One question that always seems to crop up when you take On shoes off-road is whether stones can get stuck in the sole. I’m very happy to say I didn’t have this problem once. Rather than the traditional clouds with horizontal gaps all the way down, there’s only gap vertically down the middle of the rear half of the sole and I had no issues with things getting stuck in there.
In summary, this is a great, light-feeling (295g), cushioned, flexible shoe for doing big miles on harder trails. The materials are really high quality, which bodes well for durability, and justifies the higher price tag of £160 (which isn’t out of line with similar shoes from Hoka or inov-8). If you’re looking for a shoe for summer ultras, this could be it.
Find out more at the On website here.