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Le Col Womens Deep Winter Base Layer



Very warm and breathable fabric, but the fit won't suit all and can affect comfort
Very warm
Long neck
Good moisture management
It isn't cheap
Quite short in the body

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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The Le Col Women's Deep Winter Base Layer provides excellent warmth while maintaining breathability, and it covers the neck nicely. It is expensive, though, and for the price I would have hoped for a more comfortable fit.

Check out our guide to the best cycling baselayers for more options.

> Buy now: Le Col Womens Deep Winter Base Layer for £80 from Le Col


The Deep Winter Base Layer is made using Polartec Alpha, a teddy bear-like fleece material I haven't tested before. Polartec says it's been designed for the US Special Forces 'for consistent warmth, while allowing greater breathability during activity'.

The Alpha fleece material is used across the front of the garment and upper back, made up of a loose knit so it provides airflow yet warmth at the same time. It kept me very warm and seemed to regulate my temperature well.

The rest of the garment – arms and lower back – is another Polartec fabric, Power Grid, which has a woven pattern on one side and a more conventional finish on the other. This aims to increase warmth and breathability while keeping a low weight.

2024 Le Col Womens Deep Winter Base Layer - Polartec logo.jpg

A great addition to the baselayer is the long neck, also incorporating the Power Grid fabric. I'm not usually a fan of separate neckwear so I welcomed this feature. It provided a snug yet non-restrictive fit and helped prevent wind chill effectively. It can't be removed, so some may find it limits temperature regulation, but then this baselayer is designed for the coldest of days.

2024 Le Col Womens Deep Winter Base Layer - collar 2.jpg

I combined the Deep Winter Base Layer with a fleece-lined long sleeve jersey in temperatures of between 3 and 6°C and my core stayed very warm. I didn't feel like I was overheating up climbs or cooling down too quickly on descents. I did notice a bit of 'dew' on the outside of the fleece, showing that the fabric was transferring moisture away from my skin, but positively, the baselayer never felt wet.

When paired with Le Col's Women's Hors Categorie Jacket II, which also features Polartec Alpha fabric in the thermal lining, I was at no risk of being cold on rides down to freezing, even having to unzip my jacket slightly when going uphill. However, I would have preferred for the Alpha fleece material to have extended down my back further, to help keep my lower back and kidneys warm.

2024 Le Col Womens Deep Winter Base Layer - back.jpg

While the mesh-like structure of the fleece material feels relatively fragile and prone to snagging, it is an inner layer so should hold up over time, and has survived multiple washes so far.

Size and fit

This baselayer is available in five sizes ranging from XS-XL (though it's currently only available in XS, L and XL); I chose a size S based on the size guide and my usual size in cycling kit.

I was disappointed with the fit of this garment, which reduced the overall comfort. The Polartec Power Grid fabric is tight-fitting and stretchy, while the Alpha fleece material is loose-fitting with minimal vertical stretch. This resulted in the body being short and loose, barely reaching my belly button at the front and slightly shorter at the back, and the minimal vertical stretch meant it couldn't be pulled down, which compromised the warmth of my lower back.

2024 Le Col Womens Deep Winter Base Layer - hem.jpg

In contrast, the sleeves felt tight to put on, although once on they weren't restrictive. The snug fit actually allowed for effective layering underneath a winter jacket if needed. Despite the initial snug fit, the sleeves were still a good length on me, which is something I tend to struggle with.

2024 Le Col Womens Deep Winter Base Layer - tail.jpg

At this point, I would typically recommend going up by at least one size, but the other parts of the garment fitted well, and I'm unsure if opting for a larger size would add enough extra length without making the baselayer excessively baggy.


The Le Col Women's Deep Winter Base Layer doesn't come cheap, and you can certainly pay less.

The Craft Active Extreme X Round Neck Long Sleeve Women's baselayer retails at £45 and you can currently get your hands on it for £25. Tester Emma said that it was difficult to fault, ticking all the performance boxes for breathability, wicking, ventilation and warmth, with a functional and comfortable fit.

Another baselayer specifically designed for extremely cold weather is the Assos Women's Ultraz Winter LS Skin Layer. It's even more expensive at £110, but Emma found that it was top notch in every aspect – fit, comfort, warmth and moisture management.


This baselayer has a lot of potential, as the performance is good and the fabric works well; I would struggle to justify the price given the fit on me, but if you think it'll work for you, it's worth trying.


Very warm and breathable fabric, but the fit won't suit all and can affect comfort

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Make and model: Le Col Womens Deep Winter Base Layer

Size tested: Small

Tell us what the product is for

Le Col says:

"The Deep Winter Base Layer is our warmest base layer, developed with and chosen by pro riders when training in the off-season. Using advanced Polartec® fabric technology, the base layer optimises performance efficiency by delivering thermal protection and breathability while keeping weight to a minimum."

Tell us some more about the technical aspects of the product?

Le Col says:

"Polartec® Power Grid™ is strategically placed across the arms and lower back. The fabric uses a patented geometric grid construction which traps warm air to boost warmth while creating open air channels for effective moisture evaporation and improved breathability.

Polartec® Alpha™ is used across the core and upper back for supreme targeted insulation. Engineered for consistent warmth, the fabric ensures your temperature is regulated when riding at varying speed – whether you're tackling a hard climb or descending at pace."

Le Col lists:

Designed for any riding style in cold conditions

Polartec® fabric technology

Close-to-skin fit

Lightweight and low bulk fabrics

Advanced moisture management

Supreme insulation

Temperature regulating

High breathability

Extended collar designed to further lock in warmth

85gsm fabric weight


100% Polyester

Care instructions

Machine Wash at 30°C / 86°F

Do not use fabric conditioner

Dry flat, do not tumble dry

Do not bleach, iron or dry clean

We'd also suggest turning inside out prior to washing and keeping them separate from other items by popping them into a mesh laundry bag

Rate the product for quality of construction:

Seems well made, though the Alpha fleece material feels quite fragile.

Rate the product for performance:

The Polartec fabrics do a great job of keeping you warm while remaining breathable, but the poor fit compromised warmth on my lower back.

Rate the product for durability:

No issues with durability so far.

Rate the product for fit:

I was disappointed with the fit of this garment on me, which reduced the overall comfort. The Polartec Power Grid fabric is tight and stretchy, while the Alpha fleece material is loose, with minimal vertical stretch.

Rate the product for sizing:

According to Le Col's size guide, my 34in chest put me firmly in small territory, but I found it very short in the body.

Rate the product for weight:

A very good weight for the level of warmth provided.

Rate the product for comfort:

The fabrics used are certainly warm and comfortable, but for me the overall comfort was compromised by the length of the baselayer.

Rate the product for value:

There are certainly cheaper options out there that do as good a job. The technology of the fabrics work well, but I'd expect the garment to fit better for the price.

How easy is the product to care for? How did it respond to being washed?

The Polartec Alpha fabric has stood up to multiple washes so far.

Tell us how the product performed overall when used for its designed purpose

Le Col has aimed for a warm winter baselayer that is light and breathable, which has been achieved with the Polartec fabrics; it's the fit for me that lets it down.

Tell us what you particularly liked about the product

It's warm and breathable.

Tell us what you particularly disliked about the product

The fit.

How does the price compare to that of similar products in the market, including ones recently tested on

It's certainly not cheap, but there are more expensive options such as the Assos Women's Ultraz Winter LS Skin Layer. There are also cheaper options that do equally as good a job, though, such as the Craft Active Extreme X Round Neck Long Sleeve.

Did you enjoy using the product? Yes

Would you consider buying the product? Not for me.

Would you recommend the product to a friend? Maybe

Use this box to explain your overall score

The performance of the baselayer is good, and the fabric works well, but I struggled with the fit, which impacted on comfort. That's personal, so I'm going for 7 as the fit might work for you, though it is expensive.

Overall rating: 7/10

About the tester

Age: 23  Height: 175  Weight: 64

I usually ride: specialised tarmac sl6  My best bike is:

I've been riding for: 10-20 years  I ride: Most days  I would class myself as: Expert

I regularly do the following types of riding: road racing, commuting, club rides, general fitness riding, fixed/singlespeed, mtb,

Emily is our track and road racing specialist, having represented Great Britain at the World and European Track Championships. With a National Title up her sleeve, Emily has just completed her Master’s in Sports Psychology at Loughborough University where she raced for Elite Development Team, Loughborough Lightning.

Emily is our go-to for all things training and when not riding or racing bikes, you can find her online shopping or booking flights…the rest of the office is now considering painting their nails to see if that’s the secret to going fast…

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