Original Mountain Marathon (OMM)
Looking to strike the right balance between warmth and weight is difficult when conditions on the OMM can vary between wet and wild at one extreme and decidedly chilly, even freezing, at the other. On cold mountain nights one wants to rest and sleep well.
OMM Sleeping Bags
The two PHD sleeping bags which have been chosen most frequently for the OMM are the Minimus and the Minim 400. The Minimus excels at saving weight and bulk in your pack, while the Minim 400 ensures secure warmth if the temperature dips. Both bags are also available in “K-Series” variants, using lighter materials and 1000 fillpower down to give the same performance but at a lower weight.
The Minimus has been used below zero on many occasions, but mostly in competitions where only one or two nights camping were involved. The OMM can be a fully committing mountain race and under cold conditions the argument for extra comfort (Minim 400) is strong. The Ultra K, the lightest of all the PHD bags, is a third option, if down clothing is included in your kit list (See the notes below).
Both the Minimus and Minim 400 are useful all-rounders which lend themselves very well to the OMM.
The basic figures for the above bags:
|S-bag||TOT (Min Temp)||Weight||Packed size|
Hght x Diam (cm)
|Minimus||5||41||465||16||21 x 13||284|
|Minim 400||-5||23||670||24||28 x 17||347|
|Ultra K||8||46||330||12||21 x 13||317|
|Minimus K||5||41||380||13||21 x 13||364|
|Minim 400 K||-5||23||585||21||28 x 17||458|
- TEMPERATURE RATING: Put simply, these are the temperatures at which you should be able to get a night's sleep in normal circumstances. For fuller details about the TOT rating see this Technical Briefing.
- LINERS: A liner will add to the insulation if you choose the Minimus or the Ultra K, but want more warmth. As always it is a trade-off between the extra weight and bulk and the warmth you gain (maybe 2C). Silk liners at 140gm are a popular choice, but for a greater boost of extra warmth, our K-Series Filler Bag will add 10°C to the bag’s TOT for a weight of just 240gm..
- CLOTHING: Thermals (if you are taking them) and/or other clothing obviously help to keep you warm. If choosing the Minimus or the Ultra K, then Wafer clothing adds considerable warmth for minimal weight. Even warmer but still very light is the K-Series Ultra Down Vest at 150gm. See the Clothing section below for more details.
- FABRIC OPTIONS: The Minimus and Minim 400 come as standard with M1 outer fabric. MX and Drishell are the other optional outers for these two bags. MX is exceptionally tough but nevertheless reduces the total weight by about 18gm. Drishell is highly wind/water resistant and adds about 40gm to the total weight. The K-series versions of these bags come with MX as standard, with Ultrashell as the water resistant option. Ultrashell adds about 18gm.
- ZIPS: None of these bags has a zip. Zips are an option, but most competitors don't ask for one. A short zip with draft tube adds about 50gm (2oz): a full zip and tube adds about 110gm (4oz). Zips also add to the packed size.
- PACKED SIZE: PHD stuff sacs tend to be on the loose side. All these bags can be compressed further in your sac, particularly the Ultra K.
Figures for Fabric options:
|S-bag||Materials||TOT (Min Temp)||Weight||Packed size|
Hght x Diam (cm)
|Minimus||MX outer||5||41||440||15.5||21 x 13||307|
|Minimus||Drishell outer||5||41||505||18||21 x 13||316|
|Minim 400||MX outer||-5||23||645||23||28 x 17||370|
|Minim 400||Drishell outer||-5||23||710||25||28 x 17||379|
|Minimus K||MX outer||5||41||380||13||21 x 13||364|
|Minimus K||Ultrashell outer||5||41||398||14||21 x 13||396|
|Minim 400 K||MX outer||-5||23||585||21||28 x 17||458|
|Minim 400 K||Ultrashell outer||-5||23||603||21||28 x 17||490|
OMM Down Clothing Selection
The OMM weekend commits the racer to a quite considerable time at the evening campsite after the first day's racing. What's more, the clocks move back an hour at 2:00 a.m. on the Sunday morning, meaning an even longer period in camp before the chance to warm up on the second day of racing.
The use of down clothing to create a layered Sleep System while in your sleeping bag – and for wearing around camp of course – is worth considering for ultimate weight saving and provision of warmth. Our Wafer range of clothing was designed with this in mind: a fraction of the weight of fleece (and an even smaller fraction of the bulk), but totally windproof and capable of keeping you warm down to round about freezing point. Warmer than that is the Ultralight range: The Ultra Vest K weighs only 150gm, which is lighter than most T-shirts, yet it will provide real warmth down to approximately -5°C. The Ultra Pullover K is the sleeved version, and at just 230gm represents another very useful option. Along with these, our Minimus Down Trousers and Minimus Down Socks will add considerably to the performance of your sleeping bag.
The next Original Mountain Marathon will take place 27th - 28th October 2018:
Photo: Eric Rayner