Sportful Merino Long Sleeve Women's Base Layer review: cold-weather comfort without any bulk.

Sportful has been producing cycling gear for over forty years now. The company was originally established in 1972 as a ski clothing manufacturer. This goes some way towards explaining why I always find its base layers and accessories among the best on the market. Its latest merino base layer is no exception. I wouldn’t pigeonhole it as just cycling gear - it’s great for hiking and running too, if that’s your thing - which arguably makes it better value for money.

Construction

Sportful says the layer is ‘engineered with a unique blend of merino wool and polyamide’, adding that it is ‘enhanced with exclusive Techwool technology…to offer maximum warmth while remaining lightweight’. Specifically, the top comprises 60% polyamide, 30% wool, 7% elastane and 3% polyester.

Looking at the top, and indeed wearing it, I wouldn’t have guessed that there was any merino at all; it’s a lightweight, thin fabric that feels smooth against the skin. Indeed, there isn’t a huge percentage of wool when compared with, for example, Rapha’s Long Sleeve Merino Base Layer, which boasts 74% merino, or Castelli’s Seamless Merio Base Layer with a whopping 82%.

There is no variation in the fabric throughout the top. Panels are neatly stitched without a loose thread in sight. I didn’t notice the seams when wearing the layer - always a plus in my book.

Sleeve and body length are good - neither too long nor too short. The neckline is a well-judged height; anything higher could be overbearing in milder temperatures.

The Ride

The fabric impresses immediately. It’s quite soft to the touch; I’ve had cosier but it certainly doesn’t scratch. With an accommodating stretch, there’s no sense of pinching or tightness; it really does glide over the skin. If you like compression in a base layer, this isn’t for you. The thin fabric makes the top an ideal partner for snug jerseys and jackets.

I tested a size medium, despite Sportful's website suggesting a large. The large was too roomy for my liking, the photos show the good fit with the medium. If you're on the borderline of two sizes, consider sizing down.

At just 135g (for a size medium), it doesn’t feel like a winter layer. To its credit, I’ve been comfortably warm using it in the coldest weather we’ve had to date this autumn. I admit, it’s hardly been a cold autumn so far. Roll back to October and I managed some testing on mornings when there was a layer of frost on the verges in the lanes - this certainly gives you an idea of the layer’s capabilities - I was perfectly warm enough. The temperatures soon rose on said frosty mornings and by midday the mercury had crept into double figures. At this point I was on the verge of being too warm. In Sportful’s defence, a temperature range of 0 to 10℃ is suggested. I continued to ride, curious how it would handle the inevitable perspiration. The fabric doesn’t become weighty and, thankfully, it’s fast drying. At no point did I feel uncomfortably damp. I’d say this is where it may outperform those with a greater percentage of merino as moisture simply evaporates more quickly.

Back-to-back days of riding (wearing the top) were a good test of whether or not the wool content is sufficient to prevent odour build-up. It’s coped well during testing, invariably handling four outings before hitting the laundry pile. This is a positive in my book; it cuts down on washing machine usage, and helps prolong the life of the top (by avoiding fabric deterioration through over-washing). Let’s not forget that there is still a good percentage of man-made fibres present, so there’s no guarantee that a routine of ’several wears before washing’ will hold out in the long term.

Value and Conclusions

Merino content pushes up the price of any garment. The warmth, longevity, and environmental benefits fully justify this in my opinion. However, given the low percentage of merino in Sportful’s base layer (by comparison to some others), I feel like £80/$120 might be a little overpriced. Rapha’s, with a greater proportion of merino, is also £80. Make your own judgement.

I’ve enjoyed using the base layer and will certainly continue to do so. It’s a great piece of kit that’s comfortable, versatile, and ideal for the range of temperatures we get in autumn and winter - it performs as well as any other when the mercury is sitting between 0°C / +32°F and 10°C / +50°F.