Buyers Guide To Baselayers

If you have a wardrobe of expensive technical outdoor clothing you want to be sure that it is working at it’s absolute best when you are active in the mountains. There is no point, for example, buying a waterproof jacket bursting with breathability if the garments you are wearing underneath are not transporting the sweat from your body to pass out into the atmosphere.

Sweat is natural temperature regulation allowing our bodies to maintain a safe temperature through evaporation while exercising or in a hot climate. Effective sweat management starts from the fabric next to your skin…….

Why do base layers have to be close fitting?

Water conducts heat thirty times faster than air. This means that when we are wet – we feel cold.

In our maritime climate, sweat is very much part of physical activity and when we head out into the hills we need to manage it so we can stay as dry as possible. The drier we are – the warmer we will feel. For a baselayer to begin the process of transporting moisture, or sweat, away from your skin it needs to be touching it. Moisture can then be absorbed into the fabric and start it’s journey away from your body. out into the atmosphere. A snug fitting garment will mean this physical process can work as efficiently as possible.

What do “wicking” and “moisture transfer” mean?

Wicking is a natural process  of water flowing in a narrow space without the assistance of gravity. The simplest way to see how wicking works is by putting a drop of water on a hard surface and then waving a piece of tissue paper over the drop. Nothing happens. Now, if you dip the corner of the tissue in the drop you will see the water flows UP into the tissue so that very little is left on the surface. Magic! A wicking fabric will draw moisture/sweat away from your skin and dry quickly by moving it to a larger surface area.

So, for wicking to work efficiently, fabrics need to be able to “pick up” or transfer the moisture/sweat from your body by touching it (close fitting base layers are key to this) so they can pass it onto the next layer and so on.

Will a baselayer make me sweat less?

No.

Whatever some marketing departments may tell you: clothing will not make you sweat any less. Genetics, personal metabolism and fitness are the key factors here. Sweat is your body’s natural response to cooling and emotion. If you are too hot, you sweat. If you are nervous, you sweat. In fact, one study has even found that when we are happy we produce a certain odour that indicates happiness. This scent is then detectable by others, stimulating a feeling of happiness in them as well – so sweat really is a good thing!

By understanding and using wicking clothing correctly we can manage our sweat to comfortable levels by adding and removing layers.

However, if you can feel sweat on your brow then even your skin can’t get rid of it fast enough. When this happens your clothing has got no chance. Sometimes, all that may be required is to manage our own exertion – just slowing your pace a little can work wonders.

What’s the difference between baselayers and thermal underwear?

The key element in technical outdoor baselayers is that they wick to transfer moisture away from your body as efficiently as possible. Baselayer tops and bottoms come in all sorts of styles and weights so you can choose garments suitable for the outdoor environment you will be active in. Lighter weights for warmer climates and heavier weights for cooler or high-altitude environments.

Thermal underwear is designed purely to keep you warm and offers a cost effective option for periods when you are inactive. As warmth is a priority, designs may not allow for active movement and the fabrics will have been chosen for their insulation properties over wicking abilities.

How do I choose between synthetic or natural fibre?

Synthetic wicking fabrics are petro-chemical based and can work by chemical treatment to the fabric or mechanically; by knitted yarns designed in specific shapes to transport moisture efficiently. A chemical wicking finish is cheaper than a wicking yarn but over time it will wash out. Some synthetic baselayers contain a high percentage of recycled content too. They are light weight and extremely quick drying as they excel at transporting moisture; it’s what they have been designed to do. Synthetic fibres are not very good at releasing odour so a good synthetic baselayer will have an anti-odour treatment built in.

Wool baselayers are naturally odour resistant due to the fibres’ unique properties, they release odour efficiently during washing and love water vapour; happily slurping it up to absorb up to 35 times it’s own weight. This means drier skin for the wearer and fewer opportunities for bacteria to thrive (it’s bacteria that cause smells – sweat itself has no odour) The downside of this means that wool baselayers take longer to dry than synthetics. Wool does, however, offer a natural fibre next to the skin, no chemical treatments and requires less frequent washing. All wool baselayers will have a percentage of synthetic fibre included to retain shape and improve longevity. Please, please only buy merino wool clothing that comes from farms certified non-mulesing as this horrible process causes distress to the animal.

To find out what a garment is made from simply look inside the left-hand seam – all clothing has a small white label required by law stating the content of the textile.

Watch out for cheaper activity clothing that claims to wick but has a high cotton or rayon content blended with polyester. The wicking properties are considerably lower and more suited to activities that don’t generate a lot of sweat.

Do I just need a baselayer for my body, or hands and feet too?

Hands and feet not only have a large number of sweat glands but as extremities, they are the first area the body takes the blood from when it needs to maintain core body temperature. Keeping them warm is extremely important. Simple liner gloves and socks can make a huge difference to keeping your extremities warm in cold climates and in the case of your hands, will offer a layer of protection/insulation if you need to remove them from your main gloves to complete fiddly tasks.

What do I do when my baselayer smells so bad I don’t want to use it any more?

As with all garments read the care label and wash it accordingly – if it says don’t use fabric conditioner then don’t. It blocks wicking yarns and prevents them functioning properly.

If regular washing no longer keeps your baselayer fresh then specialist outdoor technical garment care companies Grangers and Nikwax offer a range of wash in products and sprays to knock out those nasty niffs. Giving items a soak overnight can help too – basically keep them out of landfill as long as possible!

Top Tips To Make The Right Choice…..

Baselayers are the foundation of your technical clothing system.

Regardless of all the technical talk above the best baselayer is the one that fits your body shape comfortably and without creasing or rucking. Some will have a longer body length than others, some may have longer arms – the only way to know is to come into the shop and try them on.