Mountain Equipment Ultratherm Jacket: review

Ultratherm in action on a Welsh beach at Easter

I wrote about the Mountain Equipment Ultratherm Jacket not long after I'd bought it, back in June 2013. Since then, it's been used on virtually every run I've been on. Based on my strava activity (which is likely to be fairly accurate), since buying the jacket, I've done 284 runs and 2322km. Each time I use it I'll be wearing either a bumbag or a rucksack. It's been washed numerous times too. It's still going strong.

So why have I worn it so much? Quick answer: it's bloomin' great. That's why.

I really don't like feeling cold when I'm out in the hills. In fact, I'd rather run hot than feel a slight chill. So even on warm days I still go out with the ultratherm on. In summer I'll still set off running with a windproof gilet on, unless it's balmy hot. Over the past 6 months I reckon I've only headed out a handful of occasions without wearing the jacket from the offset. A couple of times in recent weeks, because it really has been warm enough for just a t-shirt, and other times because it was raining so heavy I needed my waterproof OMM smock. I've only used the hood a handful of times but have been happy with how it's performed. For a lightweight garment, having the draw cords to rack it in tightly on a windy wet day is a bonus.

I do a good variety of runs - some fast paced, some slower guiding and with runners new to off-road running, some hill reps where I'm pushing hard on steep climbs, getting sweaty, then waiting during the rest period. I'm impressed that the ultratherm jacket keeps me warm when I need it, yet not overheating when I'm pushing myself on hill reps or a fast paced run.

What's it like?

microfibre lining

Comfortable. The microfibre lining is really comfy. I mostly just wear a vest or t-shirt under it and it's lovely and snug. No cold feeling on my arms as the wind buffets it. The collar fits fairly snugly, enough room for a buff worn as a neck warmer when needed, but not too roomy that it flaps around.

Windproof. To a point, but I often forget it's not totally windproof as it acts like it is. There are panels in the arms and sides which aren't windproof, but it does take a very windy day for it to penetrate when you're moving. It's only really when I pause or stand around for a while on a breezy day that I feel the wind blowing through the non-windproof panels.

Hard-wearing. As mentioned above, I always run with a bumbag or rucksack. On close inspection the jacket is still looking almost like new. These next few photos show the condition after almost a year of use:

side panel - just a few ruffles but not really noticeable that a bumbag/rucksack worn on every outing

cuff, showing no signs of wear

inside collar - a tiny amount of balling-up showing

front panel, a few minor 'pulls' on the fabric
I had to look hard to find these!

no signs of wear and tear the back either

Niggles? (I really am picking at tiny little things here)

zip in collar to release hood

• The zip fastener on the hood rattles. Such a minor point. But it niggles and rattles in my left ear. After a while it annoyed me so much that I tucked the fastener in so it didn't rattle. A few runs later and the heavens opened big time, I was in panic mode with gloves on really struggling to unzip the collar an reveal the hood. Lesson learnt the hard way. A very soggy neck and back. I now have the fastener rattle rather than risk a cold wet head on the hill. I should just put some tape over the fastener, see if that quietens it.

• The vent panels on the arms. Noted above - not designed to be windproof. I'm not sure how much extra weight or breathability you'd lose by having the whole garment windproof. To me it would be worth giving it a go because there are occasions when I still carry my OMM smock in case it gets really windy/rainy/cold on the hill. I've been out in some gnarly weather in the ultratherm and it's performed great. However, I wouldn't want it to be the only jacket I took out on a longer run, or when I'm heading out on gnarly wet weather days.

• Sizing. I tried a size 10 but it didn't seem to give me enough freedom and room in the arms, so I ended up with a size 12. In reality I need a size 11. The 12 is baggy around my body; just a small niggle. If I didn't wear a bag of some sort I'm sure the bagginess would bother me more.

Best test: a few weekends ago in the Lake District...heading up Kirk Fell from Ennerdale YHA. We had a 6km run along the valley bottom to Blacksail YHA before heading up the hill in anger. It was drizzly when we set off, so ultratherm not waterproof weather. Part way along the track the rain started in earnest. By the time we reached Blacksail I had water dripping around my elbows, that really soggy feeling through all my clothing. Knowing I'd be on the hill a good few hours to come, and climbing up another 500m+ to the summit, I put my OMM smock on over the ultratherm. I could have taken off the ultratherm, but the thought of needing the warm layer later on, and having to put it on wet didn't enthuse me. I chose to be damp inside the waterproof layer, and hope I didn't get a chill.

Climbing up we were gaining body temperature, and luckily sheltered from the wind for a good part of the ascent. Topping out I'd vented the OMM smock but not unzipped the ultratherm underneath. At some point on the run (maybe on the way up) I had started to dry out on the inside. I no longer had that soggy wet feeling inside and was even starting to feel warm and comfortable once more. The rain put paid to any decision about removing the OMM smock, but had it cleared I would have been back to just the ultratherm - and a pretty dry jacket too.

Overall opinion after this run: blinking fantastic piece of kit. I will replace it (when necessary) without a moments doubt. I had no doubt prior to this run that it was a great jacket, but this run proved it's worth in really gnarly conditions.

Ultratherm mountain running in Switzerland, Aletsch Glacier up ahead

Thanks to Vicki for this photo, on Bleaklow at the B29 plane wreck

New the jacket RRP is £120. Expensive but definitely worth it. I have seen them at half that price online, but in tiny or XL sizes only. From a quick look around the internet it seems you should be able to get one for £90.  For all the technical info head over to the ME website.

For Tim's review of the same jacket, well his jacket...the men's is orange inside whereas womens is red, head over to his blog, TestedToDestruction.