Helly Hansen H1 Pro LIFA Seamless 1/2 Zip long-sleeve baselayer review

Helly Hansen's LIFA fabric was probably the first thermal wicking yarn technology – and those old enough will remember the skinny fit, navy tops with distinctively striped sleeves that gave off an equally distinctive odour when dried out over a radiator.

However, the Pro Lifa Seamless combines the very latest evolution of the LIFA technology and there's no longer any smell, with Merino wool and thermal mapping construction.

In plain English, that means warmth where you really need it and fast and effective heat shedding in the areas where it builds up.

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In practice, the baselayer is a joy to ride in, with its mix of instantly cosy Merino and the wicking, fast-drying characteristics of a synthetic.

The technology isn’t just limited to the fabric though. A seamless knit body construction means that there are no side seams for less chafing, it doesn’t twist and gives a second-skin fit that somehow manages to not to be too skinny.

The sleeves are a raglan cut (look for a diagonal seam from arm pit to shoulder), which gives a wider range of movement without pulling the body up, and the seams are flat to minimise chafing.

The Pro looks like an uncomplicated garment but it’s these technical construction details that make the difference and you don’t realise you want them until you try them.

The high neck adds extra warmth and makes this a cold weather choice. The soft, lightweight, barely-there feel means that the Pro has become a go-to for longer rides when I don’t want to have to think too much about my kit. Whether it’s worn with a full-on waterproof or soft-shell hybrid jacket the temperature regulation is superb.

On those transition days in autumn and spring, when you’re not too sure if it will properly warm up but don’t want to boil if it does, the baselayer feels robust enough to wear alone.

It’s not the cheapest baselayer, of course, but it is exceptional in terms of fit performance and versatility. If your budget stretches this far, it’s well worth the investment.