Base layer is a general term for thermal underwear which is designed for cold conditions.
Typically such clothing is made of artificial fabrics which are quick to dry and quick to wick away moisture (ie sweat) from your skin.Nearly all major outdoor manufacturers have a range of baselayer clothing comprising at the very least,long sleeved zip top,long sleeved crew neck top and tights/long johns.Base layer is not just thermal underwear,it is also important as an outer layer where it is too hot to wear anything more.
When you are active in the outdoors you are going to get hot.The body deals with this increase in temperature by producing sweat,the evaporation of which produces a very efficient cooling effect.However in reality this moisture cannot evaporate quickly enough and what actually happens is that your body ends up covered in sweat.The problem start when you slow down or stop,the excess of moisture collected on the skin continues to cool the body even though you no longer require it.This situation can cause to get cold and even can result in the onset of hypothermia.
The clothing that is worn next to the skin must allow this excess moisture away from the body and allow it to be dissipated to the air.Cotton T-shirts are not good for outdoor activities as they hold moisture and let you feel cold and clammy.Without a good base layer your investment in that expensive and highly technical jacket is something of a waste of money.
First Layer : Base layer / Long Underwear /
The function of tops and pants in this layer is to keep you dry,to provide warmth and keeping you comfortable all day.
Styles :
The most popular combination is long sleeved pullover and long pants,both are with ribbed cuffs to keep out the cold.There are other styles available as well.These include turtle neck,zipper neck,short sleeved and sleevless tops,and short style botoms.
Fit :
Base layer garments should fit close to the body to absorb moisture effectively. Generally,it is best to stick to your normal size.Tight garments will restrict your movement and loose garments can bunch or chafe.
Functional requirements :
Advances in fabric and fiber technology have provided the required softness. Functional fabrics whisk perspiration away from your body to outside of the garment where it can more quickly evaporate.When you wear functional underwear with wicking ability
a warm,dry area is created between this fabric and insulating garment you wear over it. The weight or bulk of the fabric used in the garment determines the warmth it provides. Though not necessity for a good base layer garment,anti-bacterial/anti-microbial treatments are available in some styles and offer added benefits.
Materials :
- Synhetics : Synthetic fabrics are usually the best choice for functional underwear.They provide a good combination of moisture management,softness and thermal properties.
Polyester is the most common material used,due to its excellent wicking ability.
- Silk : Silk is used especially in lightweight pieces.This material is a soft,strong,wicking fiber.
- Wool : Wool fiber naturally wicks away moisture.
- Cotton : Cotton garments are warm,soft and comfortable when you first put them on.But cotton is not recommended for functional underwear or base layer garments,because of its tendency to absorb and hold moisture.
- Blends : Blends of these fibers offer the best properties of a variety of conditions.
Layer two : insulating tops and pants
The primary function of clothing in this layer is to keep you warm.
Styles :
This layer includes a variety of tops,including sweaters,fleece tops and vests,most often
in pullover styles.Fleece or knit pants are also available.Basic cotton knits should be
avoided due to cotton’s tendency to absorb and hold moisture.Style is also a factor,as these garments can easily double as casual streetwear.
Fit :
These garments should have a loose fit for good freedom of movement,but they should also
fit under a jacket and ski pants without sagging or bunching.
Functional requirements :
Insulating garments come in various materials and weights,and these will impact the degree of warmth they offer.Moisture wicking is the ability af a fabric or fiber to move perspiration from the inner layer of the garment to its outer layer for quick evaporation.This will keep perspiration moving further away from your skin,allowing your body to keep you warm more efficiently.
Providing warmth without a lot of weight or a lot of bulk is important for general comfort but particularly for ease of movement.Materials that offer natural stretch or garments that incorporate spandex/lycra are good for those who prefer greater freedom of movement.
Materials :
- Fleece : Synthetic fleeces are the most widely used materials for insulating garments.In addition to provading warmth without a lot of weight or bulk,they are good moisture wicking fabrics and lend themselves well to both popular and traditional styles.Fleece is also machine washable and retains its shape through repeated wash and wear cycles.
- Wool : this fiber is naturally warm and moisture wicking.Wool is often bulky which makes this fiber less desirable.Wool shrinks easily as it dries and is not as easy as to care for as fleece .It may be allergic to some people.
- Cotton : Cotton is not recommended as functional underwear or base layer garments,because of its tendency to absorb and hold moisture.
Layer three : outerwear
These outer layers composed of jackets,parkas and pants which protects you from the extreme elements you may encounter.These garments should be made of wind and water resistance and breathable fabrics |