Last year I mentioned replacing the insoles in the Altama OTB Boots with Ortholite Fusion Insoles. The Ortholite insoles fit well in the OTB boots, and make the footwear zero-drop (or at least close enough to it that I can’t tell the difference). It is a lower volume insole that Altama’s default rubber one, and so requires tighter lacing. Unfortunately, the availability of this insole appears to be limited. I’ve also decided that it is a little too soft for my taste. I like a firm footbed. The Ortholite Fusion, while thin, allows my foot to sink into it slightly more than I would prefer.
When I bought my ranger green OTB boots earlier this year I could not find the Ortholite Fusion insoles in stock in my size. So I went looking for alternatives and ended up with the Sof Sole Athlete Performance Insoles. I bought mine from The Insole Store. I mention this because The Insole Store actually provides measurements for heel thickness, forefoot thickness, and arch height. This is critical information for making an informed purchase of an insole, and yet very few retailers or manufacturers provide it. The Insole Store also supports filtering by characteristics, such as walking and running insoles without arch support, which makes it easy to narrow down the wide array of options. This kind of stuff seems like it would be common sense for anyone selling footwear, but it isn’t, so I give my money to The Insole Store.
The measurements provided by The Insole Store for the Sof Sole Athlete Performance Insoles are:
- Thickness at heel: 7.75m
- Thickness at forefoot: 4.6mm
- Arch height: 20mm
I’m happy with anything up to a 4mm drop. These have a 3.15mm drop, which is close enough to zero that I can barely tell the difference. I wasn’t sure about the 20mm arch height. That’s a 12.25mm climb up from the heel, which sounded high, but I ordered the insole anyway. When wearing them, I don’t notice any rise in the arch. They feel flat, which is what I want.
It’s interesting to compare these Sof Sole insoles to something like the Superfeet Carbon Insoles. This is what Superfeet markets for low-volume, minimalist athletic footwear.
- Thickness at heel: 5.5mm
- Thickness at forefoot: 2.75
- Arch height: 30mm
The heel and forefoot numbers are great. Nice and thin, with only a 2.75mm drop. But the 24.5mm climb from the heel to the arch is ridiculous. I tried a pair of these once, and it feel like standing on a golf ball.
I’ve been very happy with the Sof Sole Athlete Performance Insoles. I ended up buying a second pair. They are trim-to-fit, but the Men’s 9-10.5 size slid perfectly into my size 10 D Altama OTB boots without any trimming. They are thicker than the Ortholite Fusion Insoles, but firmer, which I think allows for better energy transfer. The higher volume translates to a fit that is much more similar to Altama’s stock rubber insoles, but with a material that makes more sense if you aren’t planning to take the boots under water. I’ve tried wearing one Sof Sole insole in one boot and one Altama rubber insole in the other, and the fit feels nearly identical. I recommend the Sof Sole insoles if you’re unhappy with the breathability or tackiness of the insole that came with the Altama OTBs, and I think they are worth consideration for other footwear in the lightweight hiking category. They are likely too thick for minimalist running shoes.