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  1. Why A Synthetic Base Layer Is Better Than Wool

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    Why A Synthetic Base Layer Is Better Than Wool

    Fashion always seems to go in full circles, and this is no more truer than with thermal underwear. For centuries wool had been the winter underwear of choice but this changed with the invention of man made yarns in the 1940s and 50s. New materials made from these raw materials lead to the spread of the synthetic base layer towards the end of the 20th century. However, over the past decade the market has seen a resurgence of performance woollen underwear, with synthetic base layers being much maligned, albeit by woollen vested interests.

    Before people start to dispose of their ‘plastic’ underwear and adopt a more ‘environmentally friendly’ woollen clothing system, they should really consider the following points:

    User Comfort

    Wool can be itchy. There is no getting away from it. If people have sensitive skin then it doesn’t matter how soft the wool actually is, it is going to irritate the wearer. Sometimes this can be psychosomatic, but that is no comfort if you are on top of a mountain scratching away.

    Synthetic fabrics on the other hand have a very soft handle, especially polyamide, that rarely irritates the skin. The long smooth fibre profile glides over the skin rather than scour it. This smoothness also helps other items of clothing to glide over a synthetic base layer, helping to prevent rubbing and chafing.

    Longer Lasting

    Being a natural product, wool will degrade over time. This was fashionably demonstrated by HRH Prince Charles who buried an old woollen jumper. Although this composting ability is seen as a major advantage it does have the disadvantage in that the longevity of a woollen base layer is short. You will be lucky if one set lasts you a season if used regularly.

    In comparison, a synthetic base layer will not degrade, well not in your lifetime anyway. Viewed mainly as a negative to the environmental lobby, this is in fact a positive – a thermal base layer for your lifetime. Most people only change their synthetic base layer if a) they loose it b) they boil wash it and shrink it c) change body shape that means the fit is no longer good d) fancy a different colour.

    Better Moisture Management

    Wool acts a bit like a sponge, soaking up moisture when in contact with it. Defenders of this process will state that it doesn’t feel wet, it’s just absorbed internally. OK, this is true for about 25% absorption, but if you fall in a body of water you are going to have a very heavy base layer. Just feel the weight of a washed jumper before the spin cycle.

    With a synthetic base layer basically being made form plastic, water absorption within the yarn is very low, and is in fact 0% in polypropylene base layers, effectively making them waterproof. The construction of the garment will dictate how much water is actually held (rather than absorbed) but this is often marginal. With these base layers, and especially polyamides, you can impregnate hydrophilic treatments in to the yarn itself to further aid moisture movement.

    Superior Washing

    Most people will have probably shrunk a woollen jumper at some point in their life. Its a natural reaction by the wool fibres to heat, water and mechanical action to want to revert back to their original curly shape. Think of straightened frizzy hair after getting rained on. Some woollen base layer can be washed on a cool cycle with no spin, but most recommend hand washing and line drying, which is ideal in the summer, but a pain in the bum in the winter when you are going to use them the most.

    Don’t get me wrong, synthetic base layers will shrink at high wash temperatures, but put them on a washing machine spin cycle at 30-40oC and you will have no issues. Due to their low water absorption, they will also dry much quicker.

    More Environmentally Friendly

    If you interviewed most outdoor enthusiasts, the vast majority would probably believe that woollen base layers are more environmentally friendly than synthetic versions. You can understand why. It’s a natural product that rots down and absorbed back in to the earth. But scratch a little further and all is not as it would seem. Wool is not something you just sheer off the back of a sheep and wear. There are a lot of energy intensive processes involved to get a finished product that is relatively soft and user friendly. So if you are having to buy one woollen base layer a year, over your lifetime that is a lot of energy and resources used.

    In contrast, a synthetic base layer may not be biodegradable but it will last a long time and is a lot more robust. You may only ever need one thermal set in your lifetime if you are lucky enough to stay the same shape. Once you have finished with, it can also be recycled in to the next base layer for someone else lifetime.

    Purchase Price

    For just coming off a sheeps back, the cost of a finished wool product is very expensive, mainly due to the amount of processes involved. A new set every year is going to be cost prohibitive to a lot of people, especially with the added risk of laundry damage and natural wear and tear.

    A good quality synthetic base layer of comparable weight and style will probably be around 15-25% cheaper. Once you start to multiply the cost by the lifetime of the garment, you are getting a lot more bang for your buck with a synthetic base layer.

    When Wool Should Be Used

    There are certain situations where we would advise woollen base layers to be used. If any person has the possibility of contact with fire such as in the aviation industry or the emergency services, then woollen base layers are ideal, as the fabric chars rather than burns. There are also industrial applications, such as welding, where sparks or high temperatures may be around the wearer.

  2. What Is Thermal Mid Layer Clothing?

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    Thermal mid layer worn by two cross country skiers in the Alps

    Most outdoors people understand what a base layer is and the function it performs in keeping you warm and dry. However, when it comes to a thermal mid layer there is still a lot of confusion about its purpose and what one exactly is.

    PURPOSE OF A THERMAL MID LAYER

    The primary role of a thermal mid layer is to add extra insulation to your layering system without being overly bulky. It is usually worn over your base layers but some garments, like our Factor 2 mid layer range, can also be worn directly next to the skin.

    Its secondary role is to carry on transporting moisture away from your skin via your base layer to the next layer of clothing. If your mid layer has poor wicking properties then you are going to get damp very quickly when working hard. This can lead to rapid heat loss when you slow down or stop.

    TYPES OF THERMAL MID LAYERS

    Personally i think a lot of companies wrongly label garments as thermal mid layers, such as micro fleece jackets and lightweight down jackets. For a start they are far too baggy to be true mid layers and are often poor at managing moisture. A lot of the time it is a clumsy attempt by a brands marketing team to adhere to the layering system – base layer, mid layer, outer layer – when their range is not complete or when their range is too large.

    Our classification of a mid layer is pretty simple. It should be snug fitting, offer good moisture management, and be insulating. Basically it is a thicker version of a base layer. When we were developing our  award winning Factor 2 mid layer range, we took these parameters and designed a bespoke fabric around them. Nearly three decades later our Factor 2 is still one of the best thermal mid layers you can buy.

    WHEN SHOULD A THERMAL MID LAYER BE WORN?

    Deciding if wearing a thermal mid layer is necessary is dependent on the weather conditions, the activity you are intending to perform, and ultimately your own personnel tolerance to the cold. If in doubt, always err on the side of caution, as you can always remove a layer.

    For a relatively sedentary activity such as fishing where little heat is generated from movement, you are going to want to wear as much insulation as you can to ensure you trap and retain body heat.

    On the other hand, if you are a proficient skier, then you are going to have an aerobic workout even in very cold temperatures, so overheating may be a problem wearing a full layering system. In this situation we would recommend wearing a base layer top and bottom with just a mid layer top to protect your core. If you find you are getting too warm then you can always remove a layer relatively easily.

    For extreme cold conditions, such as polar expeditions, then a good base layer and thermal mid layer are a necessity, and a re just the start of your layering system.

  3. How Tight Should Base Layers Be?

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    How tight should base layers be? - Sub Zero Factor 1 Plus base layer zip turtle top being worn correctly by a skier

     

    The two most common questions we get asked are how tight should base layers be? and what is the difference between base layers and compression layers? We will deal with the latter question in the next few weeks , but this post will hopefully enlighten you on the correct way to wear base layers.

    ARE BASE LAYERS SUPPOSED TO BE TIGHT?

    The simple answer is it depends on your definition of tight. To me, tight means restrictive and uncomfortable, which is obviously a hindrance and a distraction when performing an outdoor activity. It has entered the vocabulary of performance clothing as the dividing line between base layers and compression layers has become blurred by marketeers. We try and avoid using ‘tight’ altogether when talking to our customers, preferring a more softer wording such as ‘snug’.

    WHY NOT WEAR BAGGY BASE LAYERS?

    This is the other extreme. You may think you look cool with your bum hanging out your base layer leggings (obviously a matter of opinion) but they won’t keep you warm. Badly fitting thermals will lead to all sorts of problems such as heat loss, vastly reduced wicking rates (transportation of moisture), and possible skin sores from rubbing of excess material.

    HOW SHOULD BASE LAYERS FIT?

    Base layers need to be close fitting to prevent warm air trapped between your clothing from being wafted out during movement. A close fitting base layer will also be much more efficient at moisture management due to a higher fabric surface area being in close contact with your skin.

    When trying on a base layer you need to understand that the fabric has been designed to be stretchy so it will naturally adjust to most body shapes. What you should be looking for is the correct length in the arms (finishing just over the wrist) and the length of the body resting on the top of your bottom.

    A good way to check  if the base layer is too tight is to see if you can pinch any of the fabric and pull it away from your body. If this is difficult to do then you more than likely have a size too small. Another area to check is under the armpits. If you cannot get the full rolling movement of your arms and shoulders then you need to try the next size up.

    SO HOW TIGHT SHOULD BASE LAYERS BE?

    In answer to the original question, base layers should be snug fitting but not restrictive. Warm air needs to be trapped between fabric layers without the possibility of it being wafted out if you are to stay warm – the air is the insulator. At the same time, you don’t want the base layer to be so skin tight that it restricts movement or even blood flow.

    So my final piece of advice is if it feels too tight then it probably is.

  4. Thermal Clothing For Extreme Cold

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    Two arctic explorers in full Sub Zero thermal clothing for extreme cold weather

     

    Wearing the right layer of thermal clothing for extreme cold situations can be the difference between life and death if you get in trouble. Wear too much insulation and you will overheat, increasing your perspiration, that will rapidly cool your body when your intensity levels drop. Alternatively you may not be wearing enough thermal layers to start with. This can also lead to rapid heat loss unless remedied, forcing your body to shut down to protect its vital organs. As you can see, wearing the correct layers of thermal clothing for extreme cold environments should be taken very seriously.

    BASE LAYER

    Base layers are the first line of defence against the cold. Worn directly next to the skin, they need to be soft to prevent rubbing sores from carrying equipment, offer thermal resistance to trap heat, and be effective at transporting perspiration away from the body. They are one of the most important layers of thermal clothing for extreme cold environments.

    Our Sub Zero Factor 1 Plus base layers are made form super soft polyamide yarn that has lots of in-built stretch. This allows the base layer to fit the body snugly like a second skin. A water loving chemical is also impregnated in to the yarn during the dyeing process that actively transports moisture way from the skin to the outer layers. This keeps you dry and also speeds up the drying process when washed.

    MID LAYER

    Mid layers are very similar to base layers in that they should be worn close fitting, but they contain more fibres to trap warm air – insulation. They are effectively the work horse in your range of thermal clothing for extreme cold.

    Our Sub Zero Factor 2 thermal mid layers are heavily brushed on the inside fabric face to produce an inner fleece layer that insulates your body from excess heat loss. Their very strong flat seam construction helps prevent any pressure points occurring when carrying kit.

    OUTER LAYER

    Once you have your base layer and insulation mid layer sorted then your choice of outer layer is often determined by the elements.

    If you are working hard and still feel a little cool then putting on a lightweight down jacket will help to add extra insulation without adding much extra weight as a burden.

    If you are comfortably warm then you may not even need an outer layer at that point in time but you should keep a close eye on the weather and anticipate changes in conditions. Likewise, if you have to stop or your activity levels decrease then you will need to add further layers to compensate for the reduction in heat generation.

    One mistake that even the professionals sometimes get wrong is underestimating the power of wind chill on your bodies temperature. It may look lovely and sunny outside but any wind can rapidly cool the body. Carrying a lightweight windproof that can quickly be thrown over your under layers should mitigate a lot of the wind chill effects.

    For further information on wind chill visit the Met Office

    HATS & GLOVES

    It is a myth that you loose most of your body heat through your head, at most it is around 10%. Even though the percentage is a lot lower than most people think, it is a good way to fine tune your bodies temperature. If you start to get a bit warm, remove your fleece hat or balaclava. If you are still warm after a few more minutes of doing this then you know you need to remove a larger layer of clothing.

    This also works the other way around. Add a hat if you start to feel cool. If this dosen’t warm you up then you know that a larger item of clothing needs to be worn or that you need to start looking for shelter.

    The other reason for covering your head and hands is to help protect your extremities from wind burn and frost bite.

    THERMAL CLOTHING FOR EXTREME COLD

    Keeping warm and dry in extreme cold weather needn’t be too much of a problem if you listen to what your body is telling you , are aware of your surroundings, and are wearing the correct kit.

    Luckily Sub Zero have over 40 years experience manufacturing thermal clothing for extreme cold conditions, with many polar explorers and mountaineers placing their trust in our products.

  5. Independent Trekking Tips And Advice

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    Choosing not to join a commercial trek is an attractive alternative for many adventurers and is an option enjoyed by tens of thousands each year around the world. Without the support of fellow-trekkers and tour leaders, it means taking more personal responsibility for the obvious matters such as permits, route finding, accommodation and food. Not so obvious before setting out are the practical considerations on the trail each day.

    Go lightweight – resist the temptation to pack for every eventuality. Your rucksack will weigh you down, hold you back and, ultimately, demoralise you. Modern outdoor clothing is light, flexible and easy care. A baselayer top or two will double as T-shirts and an insulating mid layer worn over it and under a waterproof or soft shell jacket allows you to be comfortable in a wide range of temperatures and weather. You certainly don’t need to pack changes of clothing – wash, rinse and dry quickly is the best way.

    Feet – if you’re not used to hiking day after day, take it easy at first and check your heels and toes regularly. Boots or shoes that you know you can wear comfortably day after day are a much better bet than a brand new pair of tough trekking boots. Good socks – and a spare pair – make all the difference to comfort and foot care so change them during the day rather than each night. When you take a break, whip off boots, remove insoles and socks and let them all dry as your feet air off and cool down.

    Drinking – water, that is, not local firewater! Avoiding dehydration is a key component in staying healthy and making good decisions. Drink water regularly – by the time you feel thirsty, it’s already becoming too late. Filter or otherwise treat water you think is safe to drink and top up yourself as well as your bottle at every opportunity. Hot drinks from local stalls are refreshing but beware of bottled soft drinks as they may be filled round the corner.

    Sun – Basking in hours of sunshine at altitude can cause serious sunburn. Hat, sunglasses and sunscreen are the first line of defence. Take it easy to begin with until you adjust to the conditions.

    Stay in touch – even in remote areas, it’s surprisingly easy (depressing almost!) to stay in touch with family and friends. It’s hard to get lost on popular trekking routes and, if you’re tempted to wander up a side valley on your own, try to let somebody know what you’re planning to do. Use careful judgement as to who you tell, of course.

    Take it easy – you’re not in a completion so there’s no need to stick to a schedule. If a guidebook says a trek section should take 5 hours, remember it’s only a guide not an instruction or challenge. Take regular breaks, enjoy the scenery, chat with locals and share experiences with fellow-trekkers. It’s not a race and you’re there for the whole experience. When you’ve had a break, stretch your muscles before heading out again.

    Body clock – it pays to re-tune your way of operating to make the most of each day by rising early and enjoying a long break during the day before getting your head down early in the evening.

     

  6. Sub Zero Thermal Base Layer Top and Bottom – Save £10

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    Buy a Sub Zero Factor 1 award winning thermal base layer long sleeve top and bloo john leggings and save £10.  The thermal underwear in this offer is only available in black but you can choose different sizes in the top and the bottom from XSmall to XXLarge.

     

    This thermals offer is only available at Sub Zero Store.co.uk

     

     

     

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