Since posting about the Gel Cumulus 10 a few weeks ago, I’ve seen quite a lot of Internet debate about the relative merits of Cumulus 9s versus 10s. Naturally, this made me revisit my own thoughts on the Cumulus 10, to see if I’d actually added anything of value to the debate.

Well, you can imagine my shock and horror, when I realised that I’d actually been ‘slightly stupid’ in the way I approached my previous review. You see, as a fairly high mileage runner, I thought that racking up 250 miles or so in the Cumulus 10s before writing about them would lend the weight of empirical experience to my words.

Yet I now realise that comparing the next evolution of my favourite shoes without regard to my 9s and 10s having the same mileage on them, is like writing about a fine Camembert and the relative merits of a stick of chalk.

And so, at the risk of losing my amateur status and being banned from blogging at the next Olympics, I have taken the unprecedented step (for me anyway) of comparing the two shoes under strictly controlled laboratory conditions, the results of which you will find below.

Methodology.

First, I went onto ebay, and sourced the cheapest possible BNIB Cumulus 9s and 10s I could find, in a UK size 13, normal fitting. Sadly, I couldn’t get them in the same colour, but let’s assume, for the sake of science, that that doesn’t really matter. The 9s had the tags removed too…but hey, let’s not get too nerdy about this.

I then placed, around my feet, a brand new pair of Thorlos Running Lite socks, (the Crews, if you’re interested. Not very manly, but my ankles prefer them) and headed out to face the mean streets of Southport, using the 1 mile block around my house as a test track. I went on to test the 9s, followed by the 10s. And so that even mild fatigue couldn’t skew the results, I repeated the test the next day, in identical weather conditions, but testing the 10s before the 9s. I then, on consecutive nights, ran 6 miles in each pair of shoes, first the 9s, then the 10s.

The 1 mile test.

First up were the Cumulus 9s, with their rather fetching Orange trim. Straight out of the box, they felt like a perfect fit, with acres of cushioning underfoot, and a ride that felt smooth and totally neutral. After wearing the 10s for the last few months, they were an absolute revelation, and, at the risk of infringing Nike’s marketing spiel, really made me feel like I was running on air as I made my way around the block.

Stepping into the 10s, the fit felt less satisfactory, as they do seem to have room for broader feet than mine. And even though the cushioning was just as lush as in the 9s, there felt to be more stiffness to the insoles, particularly to the outside of the foot. Once I was running, the stiffness was less evident, but the ride still put me much more in mind of the Asics Gel GT-2120 motion control shoes that I run in on rare occasions.

The next day, I repeated the exercise, but reversed the order I wore the shoes in, and still felt that the 9s felt so much more ‘neutral’ than the 10s.

The 6 Mile Test

Conditions were cold and slightly icy underfoot on both nights of the 6 mile test. The 9s went first, as I’m a sucker for chronology, and also, as it turns out, a sucker for comfort. Just as in the 1 mile test, the Cumulus 9s felt like carpet slippers, and almost as if they were part of my feet rather than a separate entity that was getting in the way of my natural running gait.

The next night, I went out in the 10s, and while they didn’t feel too different for the first 3-4 miles, I really felt the extra stiffness and support they offer over the last mile or two. Crucially though, while this didn’t cause me any muscle or joint pain, I felt that my legs were somehow more tense, thanks to the reduced flexibility of the Cumulus 10s.

The Not Really Very Scientific Findings

OK, so if you’re of a remotely scientific bent, you’re already laughing at my pseudo-nerdy methodology. Of course, I brought preconceptions to this exercise, and have merely reinforced them during the course of my ‘experiments’. On the upside though, this is a comparison between two brand new shoes, from a die-hard wearer of the Cumulus, so it should have some merit.

And my inescapable finding is that compared to the Gel Cumulus 9, the Cumulus 10 is more spacious, less flexible in the forefoot, and slightly stiffer to the outside of the foot – a quality that I anyway would associate with motion control shoes. The 10s also feel stiffer if you grab them in both hands and twist them.

None of which is to say that the Cumulus 10 is a bad shoe. I’ve covered hundreds of miles in them without any problem. Nevertheless, I may well try to source another couple of pairs of Cumulus 9s while they’re still available on ebay, merely because I like the softer, more yielding ride they offer.

Of course, I may also have to write a snotty letter to the chaps at Asics, asking them not to make the Cumulus 11s any stiffer than the 10s, as to my mind, they’re now far less neutral than previous incarnations of the Cumulus.