
If you are running a self-sufficient race or if you are going fast packing, a sleeping bag is going to be an essential item. The need to carry all your supplies in your pack quite simply means that you are constantly having a battle against weight and functionality.
It’s fair to say, that for most people a 20 ltr pack has now become the ‘norm’ for multi-day adventures and they vary considerably. But hey, we are not here to talk about packs, we are here to discuss the sleeping bag that will go in the pack and importantly provide you with warmth and comfort during the night so you feel fresh for the following day.
I have just returned from working (3rd consecutive year) at the Marathon des Sables. Arguably, MDS as it is affectionately known is the daddy of multi-day racing. To draw a comparison, it holds the same allure and respect that Western States holds for the 100-mile distance.
Now in it’s 30th year the race has seen it all. Today, the British contingent are the most represented nation at the race, closely followed by the French. Following online forums as the 30th edition came close, one question was repeatedly asked, ‘What sleeping bag are you taking?’
It was a good question and on the face of it, a question that could easily be answered by each person clearly writing the name of their chosen product. However, nothing is ever that simple and sleeping bags (along with which pack) may very well have been the most argued and discussed topic prior to the race.
One thing was apparent from a British perspective. Three names repeatedly cropped up – OMM, PHD and YETI. Armed with this information, I decided to take all three to the MDS and test them, ‘in situ’ and feedback my thoughts.
Are you running a multi-day race? Join our Lanzarote Training Camp which takes place in January every year with two-time Marathon des Sables champion, Elisabet Barnes. Along with Sondre Amdahl and Shane Benzie.
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Firstly a little background history.

OMM – (website HERE) OMM stands for Original Mountain Marathon and they have pioneered apparel, packs and products to enable runners to move fast and light in challenging terrain for multiple days.

PHD – (website HERE) PHD stands for Peter Hutchinson Designs is a UK based company who provide a range of functional and technical apparel for adventures all over the world. They offer a range of ‘off the shelf’ designs but they are renowned for their bespoke services. You can read a profile here.

YETI – (website HERE) YETI are a small German based company who specialise in down sleeping bags. They also making clothing and accessories.
THE TEST
Before I get down to the nitty gritty, I must clarify certain things. Firstly, the weather at MDS in 2015 was quite variable, we had warm days, plenty of variable wind (including sand storms) and at night temperatures dropped considerably towards the end of the week.
I alternated between bags and in particular on the first night (particularly warm) I slept in all three bags for approximately 90-120 minutes each. Also, I did this on the coolest night which coincided with the longest day.
So that you can draw comparisons, here are my personal body stats:
- Height : 5ft 9in.
- Weight : 73 (ish) Kg.
- Waist : 32″ inch.
- Shoulders : 40″ chest.
It will soon become apparent why the above stats are important. Each night I used a sleeping matt and a small travel pillow. I also had a TNF down jacket that weighed 250g as an optional ‘warmth’ layer if required. For consistency I used a ‘Exped’ dry bag for all my sleeping bags. It does add extra weight (36g) but I like the security of a bag like this protecting my sleeping bag from the elements.


Lets look at the sleeping bags in detail
OMM

OMM provide two sleeping bag options, the 1.0 and the 1.6 (as tested). As you would imagine, OMM want to make a bag or bags that are light, functional and pack small. I like two key things about the OMM bags: they are cheap in comparison to the competition and the filling is not down. By using Primaloft the OMM is functional in varied weather and as such, this bag can get wet and it will still remain warm. This does not happen with down! Of course, rain in the Sahara may well be far from your mind but remember, MDS is just one race… I am sure you will use your bag for may adventures.
OMM say:
The bag is made from a combination of materials to ensure maximum performance. The Purist bag for the Minimalist, The shell is made from PointZero, It has a DWR treatment to the fabrics face to give it a degree of water repellency and also extra stain resistance. The synthetic insulation is Primaloft Gold to give the best warmth to weight ratio available on the market, we have used different weights per panel to ensure the best technical usage of the fill. The base sheet is filled with Primaloft Gold 60g, we then put the Primaloft Gold 100g on the top sheet. The footbox is also shaped and filled with Primaloft Gold 100g to keep the feet warm. The construction is also considered as we have a loose laid outer shell and the inner stitched through to the insulation again this is to maximise insulative value and eliminate cold spots.

OMM do not provide a rating for their bags and this does cause some issues for many people. I can understand why, no rating does leave a question mark on how warm the sleeping bag will be. The bag is mummy shaped with a short zip that sits in the middle of the bag and not at the side. It has a drawstring hood and is silky soft to touch. As mentioned this bag is fast drying and has an element water repellency.

The bag only comes in one size, so, if you are taller than 6ft it’s not the bag for you. In addition, as with all the bags in this test, they are designed to be minimalist and therefore some compromises must be made. When zipped up I personally had little room to move around in the bag, this was not a problem for me. However, if you have a big chest and shoulders you may want to make sure that it’s comfortable. At £170 this bag is a bargain and I would really recommend it. On the warm nights at MDS, particularly the first night, I was able to open the zipper which allowed me to get air to my torso and cool down. On the coldest night, I zipped up, put my head inside the hood and I used the draw string to keep out any drafts. I took a TNF lightweight down jacket but did not need it, however, the addition of a sleeping bag liner or lightweight thermal top and pants would be recommended for the coldest MDS nights

Weight is good (426g) but it’s the heaviest bag here and the bag packs down really small.
PROS:
- Primaloft fabric is extremely versatile.
- 1/2 zip keeps weight lower and does offer ventialtion.
- Soft feel and comfortable.
- Price.
Price
CONS:
- Not the lightest bag
- You need to be under 6ft tall
- Not warm enough on the coldest night.
- Need a liner or base layer clothing for colder nights
What 2015 MDS participants said:
Had the omm, was cold after about 2 am every night. I’m usually a petty hot person so thought I would get away with it. Also being 6,1ft it was a little on the small side!
Used the OMM. Felt cool in the night but not uncomfortably, I like to spread out so the narrow end took some getting used to. Would use it again.
Omm1.6 cold between 3 and 5am every night and I’m quite brave when it comes to the cold
PHD

PHD make several sleeping bags and the Minimus K has become a regular at MDS. As mentioned, PHD make custom products for the entire range, however, it is possible to purchase the Minim Ultra K (330g from stock) at a cost of £263 in ‘standard’ fit. The big plus of PHD over other sleeping bags is how it is possible to customise a bag specific to your needs:
- Length – short, standard, long and extra long
- Width – slim, standard, wide, extra wide
- Outer fabric – MX or ultra shell
- Zip – no zip or short zip
Adjusting all of the above obviously alters the price, but if you are tall, wide, get cold feet, require no zip or require a half zip, PHD can give you exactly what you want! I recommend you allow time for this… don’t try to order a bag in March when you have a race in April…
For example, lets say you are small, slim build and require a half zip – Cost is £335 and the weight is 372g.
By contrast, lets say you are very tall, have huge shoulders and require a half zip – Cost is £458.28 and the weight is 588g.
A standard ‘off the peg’ Minim Ultra K with no zip in standard length and width weighs 330g and cost £263.
PHD say:
This K Series product has been created for one single reason, to take warmth-for-weight performance to the limit of what’s possible. Unique 1000 down, super-light materials, and specific design features mean that the word Ultralight now applies to this wide range of gear that will take you to the Poles as well as on a Sahara Marathon.
To those who like to shave every gm of weight off their load, the Ultra K sleeping bag is designed for you. The 10X inner brings a new soft comfort as well as reduced weight, while the unique 1000 down ensures max warmth per gram. An ultralight dream at 330gm (11.5oz).
Minim Ultra K. 330grm (Mostly selected for weight saving).
Minimus K. 380grm (designed for 5c nights – for a good nights sleep and recovery. This is the most popular choice)
Minim 400 K. 585grm (mostly selected by those that do feel the cold)
Zip options are interesting. We find for MdS we’re sometimes putting in a short zip and occasionally just a foot zip. The Design Your Own Sleeping Bag site allows foot zips: http://www.design-your-own-sleeping-bag.com/

The PHD was actually too warm for me on the warm nights and was perfect on the colder nights without any base layer or liner. It’s a real plush bag and very comfortable. The lack of a zip means temperature regulation is cumbersome. My only option was to pull the bag below my arm pits or push down around my waist. I personally would order a custom bag with a half zip given the choice. The fill is 1000 European goose down (hence the warmth).

The bag tapers nicely and doesn’t restrict in any way. The construction of the bag guarantees a great spread of down and it packs small and weighs a very competitive 380g.My bag actually weighed 392g.

PROS:
- Warm
- Packs small
- Comfortable
- Customiseable
CONS:
- Off the shelf it has no zip
- Maybe too warm for some (without zip)
- Lighter than OMM but not as light as Yeti
- You don’t want to get the bag wet.
What 2015 MDS participants said:
Used the PHD Minimus during MdS and found it to be perfect for what I needed. Compact, lightweight and very comfortable. It may have actually been a little too warm as I had one or two nights where it did too good a job. Overall very happy with it and will use it again!
I used the minimus Ian.
Super warm and I had to sleep partly out of the bag due to how well it performed, there were a couple of nights where I had to fully get in but that was more to do with the wind and sand blowing in the tent. Fitted in my small pack perfectly and very light. I would definately recommend it to others.
I used the PhD minimus. Brilliant bag, really warm and light enough. Would definately take again……if I go again!!
Had issue with the zip on the PHD Minimus: would jam frequently and mostly during the night when I needed to escape for a pee. Wondered if it was to do with sand but never proved conclusively. Grew quite jealous of the Combi being doubled up as a jacket, especially on the colder mornings.
YETI

YETI (new bag, Fever Zero above) are specialist sleeping bag makers. They offer a range of products so that you can decide on the exact bag for your needs and requirement. However, unlike PHD, they only offer ‘off the shelf’ products. The Passion One bag was extremely popular at the 2015 MDS for two reasons: small pack size and low weight. Weighing just 320g this bag has a full zipper, a real bonus for hot nights and it has Goose Down class 1 filling. It’s worth noting that if you require more warmth, a Passion Three (465g) and a Passion Five (690g) is available.
The Passion One is silky smooth, soft on the skin and on the first night in camp it was a real pleasure to have a full length zip to allow air to get around my body and regulate temperature. However, on the coldest night, I found the Passion One on the cold side and found the need for an additional layer.
YETI say:
Perfect for people who experience adventures while others sleep; who enjoy a trip with good companions; who consider flirting an adventure as well; who believe life is too short for bad design; who do not consider fashion and nature to be inconsistent with one another; who dream about flying; who believe their eyes travel as well; who consider the lightness of being absolutely bearable.

In comparison to the PHD and OMM products, the Passion One felt ‘too light’ which I guess is a good thing.

The scales confirmed that my bag was 304g, so, a good 100g lighter the the PHD Minim Ultra K and 122g lighter than the OMM 1.6. However, weight isn’t always everything… like the PHD, the Passion One comes in a choice of sizes: M, L or XL. The M is Ideal for me as I guess I am pretty much ‘standard’ size, however, big shoulders, extra height and you may struggle so rest assured that Large (6′ 3″) and Extra Large (6′ 9″) are available – obviously weight increases. The cost of the Passion One is £300

As with all the bags in this test, space is at a premium. It’s the nature of travelling light, however, I did find the Passion One offered a little more room in the toe box.
PROS:
- Lightest bag in the test.
- Full length zip.
- Draw string hood.
- Small size.
CONS:
- Not warm enough on the coldest night.
What 2015 MDS participants said:
Took the Yeti Passion One without liner, cover or mat. Found that stuffing it into my bag nearest my back provided good cushioning and saved 40g on carrying the cover The bag itself was fine, a little too warm on the first few days but the full length zip was fine for temperature adjustment; got cool on the later stages when the wind was up (i was sleeping in the centre of the tent with most airflow) and body reserves were low, but manageable. Stuck it in the washing machine when i came back which seems to have screwed up the lining.
Yeti – freezing cold with silk liner most nights except the warmer night where I did hang a leg out. Stage 4 I got in it with the space banker they had also given me and did that for a few nights (sorry tent 183 for rustling like a crisp packet)
The last three days it started shedding down everywhere as the material is so thin it split (inside)
I am a cold person hence taking liner – chose it because it was small and at one point I was going with a 14 l pack. Wouldn’t take again I would go for something warmer even if it meant a little more bulk and weight!
I used the Yeti one. Very light and packed up small. Decided at the last minute not to pack the silk liner and regretted it. Very cold on the later days of the race mainly due to wind blowing. It’s a warm bag but if you are in a draught the wind blows right through it. If you can drop a side of your tent to block the wind it certainly helps.
Yeti Passion One with no liner. Perfect choice for me. Full length zip allowed for legs to pop out on the warmer nights, and during the sandstorms the drawcord around the top meant I could really batten down the hatches & keep sand free inside. On the cooler nights I would say it was ‘just about’ warm enough, and only had to reach for my Ghost Whisperer jacket once (at about 4am after the long stage.)
For what it’s worth…

Another popular bag/ combination at MDS is the Raidlight Combi Down Sleeping Bag / Jacket. At £170 it represents real value for money as it combines a jacket and sleeping bag in one package. This obviously sounds like a great idea… However, the weight of the Raidlight is 700g. I personally prefer the flexibility of a sleeping bag and separate lightweight down jacket as this not only provides extra flexibility but reduced weight.
Raidlight say:
Raidlight’s ‘Combi Duvet’ dual purpose Sleeping Bag and Jacket. It is down-filled for great warmth to weight ratio. Perfect for use on multi-day races such as MdS or any event where duel purpose is key. At night, a warm sleeping bag and by day just unzip the arm holes, fold the bag up inside the back section, and it’s a really warm jacket.
CONCLUSION
As you can see, purchasing a sleeping bag is not as easy as you think, particularly when you are trying to pack this in a pack with all your food and other equipment for a multi-day adventure. You need to ask some very specific questions to ensure that you get a bag that works for you and fulfils your needs:
- Are you tall?
- Are you wide
- Do you sleep cold or hot?
- What is your budget?
- Do you want to use your sleeping bag for other trips?
- How important is weight?
- How important is pack size?
- Will you carry an additional base layer and/ or down/ thermal jacket?
One you have answered the above you can be very specific about what you need and it should, I hope become obvious which of the above bags is likely to be suitable for you.
I of course need to stick my neck on the line and say what my choice would be!
To be honest, it’s a relatively simple decision, I would go for a custom made PHD Minim Ultra K with zip so that I could regulate my temperature. With this bag, I would not need to carry an additional down jacket (weight saving 250g) and I could carry a small wind shell as a layer when not sleeping. Bag and wind shell £320.
But, the OMM 1.6 represents real value for money (if you are under 6ft). It provides a sleeping bag that can withstand the elements (rain) and the money saved on the bag would allow me or you to spend up to £200 on a real super lightweight down jacket that would offer great flexibility not only at a race such as MDS but at other events. Combined bag and Jacket price £370.
If I was an out-and-out racer looking for the lightest bag, the Yeti Passion One with full length zip and options of M, L or XL make this a tempting choice. But for me the money spent on making this bag small and light is potentially outweighed with the need for an additional warm layer that not only adds cost but weight. I would say that this bag and jacket may well come close to a combined cost of £500.
The curve ball comes with the Raidlight Combi Down Sleeping Bag / Jacket that provides great value for money. It’s certainly warm and the flexibility of the jacket option is attractive for some. However, it does weigh slightly more and packs larger. The cost at £170 is a bargain.
So what do you think…. what would you go with?
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