Icebug Acceleritas4-L

Icebug Acceleritas4-L

It was eighteen months ago that I reviewed the Acceleritas3 from Icebug, and it was almost a year ago that I received a pair of the ladies’ Accleritas4 for my wife to test and review. Now, having put them through their paces in a decent amount of British orienteering races, we are ready to publish this review.

I made the comment about orienteering because, although these aren’t exclusively an O shoe, they serve brilliantly for that purpose and they have become my wife’s first choice for most orienteering events.

The first thing to say about these is that they weigh barely anything. They’re around 160g in a ladies’ US7.5 which is so light you’ll barely notice them on your feet. And the really good thing about them is that they are constructed from non-absorbent materials so they don’t gain much weight when wet.>

The ‘ripstop’ material of the uppers is very strong, withstanding abrasion from the low-lying scrubby heather, scratchy brambles, and abrasive rocks that you’ll invariably find yourself running through if you’re orienteering or properly going for it off-road. My wife has worn these for a whole orienteering season and the uppers are showing far less wear than her previous O shoes from the likes of inov-8, Adidas and Salomon. Yet despite their durability they are soft and supple allowing the shoe to flex with your foot.

Icebug Acceleritas4-L


The Acceleritas4 has been improved from version 3 by scooping out the heel cup a bit more to give a more snug fit, and by lowering the back so as give the Achilles tendon more freedom. The version 3s were prone to rubbing on the back of the heel but this hasn’t been a problem in the 4s.

The fit is narrow. They’re described as being built on a ‘narrow’ last which is fine for my wife’s slender feet but my wide feet just couldn’t get comfortable in the 3s which was no good for long runs (hence only testing the ladies’ versions this time round).

Their best feature however, is the part that goes under the foot. Of most interest to me is their minimalism. They  have a heel-toe drop of just 4mm which puts them firmly into the minimalist shoe category. Your feet will have a reassuringly intimate relationship with the ground thanks to the flexible sole and the minimal depth of midsole – they have a small amount of cushioning in the midsole but only enough to absorb the worst impacts.

Icebug Acceleritas4-L


The outsole is the same as that of the 3s. It is made from Icebug’s Rubber 9 Extreme (RB9X) compound which has a remarkable ability to stick to hard surfaces and is surprisingly hard-wearing. This, combined with their aggressive tread means that you will have super traction just about anywhere. Dry rock, wet rock, loose gravel and sand, hard-pack gravel, grass, and mud. And the big deep lugs are spaced far enough apart for wet sticky mud to drop away and not clog up, leaving the soles ready to bite into your next stride.

Icebug Acceleritas4-L


The Acceleritas4 is a really great shoe which my wife has adopted as her go-to shoe for most orienteering races and for general terrain training runs, and she recommends them to anyone. Apart from the issue of their width, I agree with her – there’s nothing to not like. From a minimalist / barefoot running perspective they’ve got nearly everything about this shoe right, apart from the width that your forefoot needs to spread out naturally. I’m just living in hope that Icebug will produce a wide-fit version so that I can play too.

Icebug Acceleritas

Most people won’t have heard of Icebug but they’re a familiar name amongst orienteers especially those who have raced in Scandinavia. They’re from Sweden. As you’d expect from the country which brings us Saab, IKEA and root vegetables their shoes are innovatively designed and well made.

Scandinavia is blessed with a lot of fantastic running terrain. It is also blessed with extremes of seasons; long dark months of snow and ice and long summer months of daylight and sunshine.

Icebug design their shoes for those hardy athletes who want to continue running through their winters; those who need shoes that perform as well on wet rock and ice as they do on dry rock and trails. Icebug shoes are designed to do just that.

The Acceleritas3 is Icebug’s minimalist shoe. My wife and I have been trying out some his and hers pairs to see what they’re all about.

Categorised as ‘off trail’ with a suitably aggressive tread, they have a heel-toe drop of just 4mm and weigh less than 200g.

Ripstop nylon uppers serve the dual purpose of remaining lightweight by not absorbing water as well as being resistant to abrasion from ground level vegetation. With a rubber rand around the whole of the foot this is just the armour you need for running through wet heather, bilberries, bracken and brambles.

There is enough depth in the midsole to absorb the hits from the ground below but not so much that you lose sense of where you’re actually putting your feet. These are a minimalist shoe and they do feel like it.

The best thing about these shoes is the rubber compound used on their soles. They call it their new Rubber 9 Extreme (RB9X) compound and it was developed to provide traction where few unstudded shoes can – on wet rock.

Our regular orienteering shoes have tungsten dobs in the soles which give previously unrivalled traction on everything we might run through. To put these Acceleritas through their paces both my wife and I wore them for a two-day orienteering race over wet rocky terrain.

We were both very impressed with how the rubber soles of the Acceleritas stuck to the wet slippery granite. This, and with their weight being almost half that of our other O-shoes, is a definite selling point.

My wife didn’t realise just how sticky the Acceleritas soles are until the following day when she wore her Salomon Speed Cross shoes in the same terrain and came unstuck.

The Acceleritas are built on a narrow last, and they do come up very narrow. For my wife’s feet this gives a perfect fit, but for anything longer than 90 minutes my feet start to feel a bit like I’m running in climbing shoes.

Personally I’d be happier if they were wider, but the Acceleritas is a fantastic shoe for real terrain running. They are minimalist and light, whilst built from durable materials able to withstand the rough stuff. Their grip is gnarly; well designed for holding fast in mud and wet grass, and the rubber compound is stickier than anything else either of us have ever worn. They are ideal for winter running, fell running and orienteering. These shoes will prove to be a serious rival to the more established brands of orienteering and fell shoe in the UK.