Good stuff, I especially liked:
To begin with don't hang your hopes on wonder wicking fabrics and highly breathable shells. The fabric and outdoor companies will try and persuade you they have the technology to keep you warm and dry whatever the weather or rate of perspiration, but this is impossible because YOU'RE the problem, not the fabric.
Even a string vest, the most breathable thing you can wear, will become sweaty and raise your body temperature over 37°C if you're pushing it, so how can a layer of polypropylene or polyester ever hope to keep you from chilling? No, the first defence against overheating and chilling is to use these super fabrics correctly so they are not called on to do the impossible.
That's a nice foil to the seemingly never ending stream of nitwits that prattle on about how much they sweat in Gore-Tex and so on. Beyond using it wisely there's nothing you can do with any fabric, and perhaps the best solution lay in getting a bit fitter so you don't sweat like a pig at the first hint of exertion,
One thing I would add to this stuff because it seems completely overlooked on many forums [in fact I think I'm the only person that I've seen mention it on this one] is the role of friction between the layers. Whilst multiple thin layers is excellent advice the downside is friction between the layers, and that literally is a drag, especially on the arms and legs.
....It has been shown that the increase in weight and the number of clothing layers will increase the work load, and differences of up to 50% have been found between the friction values of dry fabrics. Friction between fabrics causes a resistance to movement and increases the workload attributable to clothing. To preserve performance and freedom of movement, it is vital to keep friction as low as possible in the body parts that have to perform large movements, such as the arms and legs. Clothing with low friction between the layers increases performance by 7-13% relative to clothing with high friction.
Clothing Physiological Properties of the New Military Combat Clothing and its Effect on Survivability and Performance in Long-Term Cold Exposure - Finnish Institute of Occupational Health
In fact, that exactly one of the reasons I still really enjoy the now very dated Buffalo gear in comparison to a bunch of wool jumpers with an anorak over the top. Not only is the system light, flexible, and easy to ventilate but because each layer has its own wind proof shell there's a high degree of slipperiness between the layers. I've described it before as like being in a well oiled set of gimbals.
The most challenging environment for conscripts' survivability and performance was not extreme cold but a combination of cold with perspiration during physical activity, external moisture and wet snow.
The weight, thickness and stiffness of the clothing and the friction between the clothing layers affect physical performance and limit movement of the extremities. The results presented here define the protection provided for conscripts by the Defence Forces' new ...
[op cit]
That strikes a chord. Sitting around in the cold and I can wrap up in a down jacket, easy. I could pile on some huge Aran sweaters that fishermen found great for standing around in the cold. I could make a poncho out of carpet for all the difference it makes. But none of those are good for me at the time when I am actually doing something,
Each additional kg in clothing weight increases energy costs approximately by 3% and each additional layer by 4%. Increased energy costs are associated with a decrease in physical performance: the decrease is task specific, and roughly comparable to the changes in the energy costs. The decrement in performance can be minimized by decreasing clothing weight and bulkiness as well as the friction between the clothing layers as well as the number of clothing layers. Minimal friction is important in sites where large range of movements is expected like in trouser legs and sleeves of jackets.
Performance and energy expenditure in cold environments.
Finnish Institute of Occupational Health
I've posted this last link before but I think it holds good. The extreme nature of expedition circumstances illustrate my point rather well:
In short, the Mountain Heritage Trust and a bunch of universities are examining and building replicas of expedition clothing from the beginning of the last century.
After assessing the insulation and wind protection of the clothing,
Professor Havenith found that the clothing worn by Scott and his team, which largely consisted of coarse layers of wool, was only marginally less insulating than that worn by Amundsen, whose team wore fur. Compared to modern day arctic clothing however, both outfits provided up to 30 percent less insulation.
During this project we discovered that overall there was not a big difference between the insulation and wind protection offered by the two outfits, said Professor Havenith.
However we did discover a difference between the friction levels within the two sets of clothing. Scotts apparel consisted of layers of coarse fabrics, many of wool, which had higher friction levels than the layers of slippery furs worn by Amundsen. This extra friction, combined with Scotts way of travelling being far more physically draining, meant that the garments his team wore would have resulted in them expending up to 20 percent more energy than generally assumed using up precious calories and supplies.
But there was one aspect of Mallorys outfit that impressed Professor Havenith the most the layering. I had discovered through the research into Scott and Amundsens clothing how important correct layering was for the energy cost, he said. With Mallory, each time he wore a coarse layer, for example of wool, he layered it with a slippery fabric, such as silk. When you package these types of fabric together the clothing moves very easily which means the movement of the person wearing the layers is not restricted and energy cost is low. The way Mallory wore his many layers would have made climbing in the overall outfit very easy. If you compare this to Scotts clothing, his outfit had a lot more friction internally which obviously has an impact on energy consumption and would slow you down. Ergonomically Mallorys clothing was very well designed.
http://www.lboro.ac.uk/service/publicity/publications/view/springsummer08/mallory.html
haha
