The temperature is dropping but how should you adapt your clothing to maximise your comfort when exercising outside? I have been talking with some of you about the layering system, a tried and tested way to optimise your body temperature whatever your level of activity.
There are three basic layers, each of which has a specific function. The base layer (against your skin) wicks perspiration away; the mid layer traps in heat to insulate you from the cold; the outer layer shields you from wind and rain. For maximum benefit all three layers should be made from breathable fabric. You don’t want to have an excellent wicking base and mid layer only for your perspiration to get trapped under a cheap non-breathable shell.
Base layers can be made from synthetic material or (more expensive) merino wool. Never use cotton. Although it’s a natural fibre it just absorbs your perspiration, getting wet and making you feel uncomfortable at best. I’m a merino wool fan myself. It keeps me warm but is very light and comfortable and I have never had the ‘clammy’ feeling that I can get with synthetic fabrics when I’m being very active. Apparently this is because merino wool is an active fibre that reacts to changes in body temperature. So it helps you stay warm when the weather is cold and cool when the weather is hot. It also absorbs body odour so you’re never stinky. Clever. A few other points about base layers:
- They come in different weights for different conditions – but select the weight dependent on how active you’ll be rather than how cold the conditions are. Remember the key function of a base layer is to wick moisture away. The principal insulator is the mid layer.
- Half zip necklines are more helpful heat regulators than crew cuts.
- If you want to go the whole hog, you can get merino wool underwear (yes, really!) and base layers to go under your walking trousers too.
Mid layers also (unsurprisingly) come in synthetic or natural materials. This is where the fleece is king. The job of the mid layer is to trap air in and keep you warm but it has to be breathable too. As with base layers, there are different weights for different conditions and levels of activity. You can buy crew, half zip, full zip and hoodies. All have their place. When it’s very cold people often use two mid layers or a mid layer and insulating layer. Down jackets (whether synthetic or natural) are extremely effective insulators. They can be super warm though so might not be great if you’re going on a very active walk. Also check how breathable they are.
The outer layer – or shell – is your protection against wind and rain. There are two types, a soft and a hard shell. A soft shell will be more breathable and is likely to be water-resistant, but not waterproof. Our Bristol Nordic walking jackets are soft shell and come with a high water resistance rating and a water repellent finish. They provide respectable wind proofing and are very breathable. I particularly like their stretch fabric, which gives me excellent freedom of movement. They are no good, though, in persistent rain. This is where a hard shell is needed.
Hard shells are wonderfully waterproof. Their drawback is that they are not as breathable as soft shells. Some waterproof jackets are not breathable at all. We’re an active bunch when we go Nordic walking so a jacket that is waterproof but breathable is an absolute must. You don’t want to get sopping wet from the inside (did you know that an average person sweats between 0.8 to 1.4 litres per hour during exercise!).
So you need a jacket with what I call a magnificent waterproof membrane. You will know this by different trade names – Gore-Tex® (used by the likes of Berghaus), eVent™ (used by RAB) and HyVent™ (used by The North Face) to name a few. They all do the same job – let water vapour out and stop rain water coming in – but some membranes are more sophisticated than others. That’s what often ratchets up the price. For instance, there are 3 levels of Gore-Tex – standard, pro and active. The variables are the degree of breathability, durability and weight. There are also different waterproof ratings for jackets – and don’t forget about taped seams. Yes it can all get quite complicated!
Luckily, all our local outdoors shops can give good advice on base, mid and outer layer options. There is abundant choice and many hybrid jackets to choose from. It’s fun looking but might take some time! Ultimately your decision is likely to come down to personal preference and budget.