X-Bionic Trekking Summerlight

X-Bionic Trekking Summerlight t-shirt
Price: £65
Country of manufacture: Italy
Weight: 114g
Colour: black
Recommended wash: 40C
Material: 86 per cent polyamide; 12 per cent Elastane; 2 per cent polypropylene
Sizes: men’s S/M, L/XL, XXL; women’s XS, S/M, L/XL.

Time was, when you wanted a t-shirt to wear when heading for the hills, you rooted around in the drawer for an old cotton top, pull it on and stride out.

Then things got technical: fancy synthetic materials; specific designs for different activities, and less chance of smelly, sweat-soaked tops.

Now, prepare yourself for the X-Bionic t-shirt.

The Summerlight t-shirt is so technical, it comes with a double gate-fold mini catalogue which also serves as the box it’s sold in, detailing the various features. And there are many.

The X-Bionic looks like no other t-shirt we’ve tested. It’s a mid-compression garment, so every square inch of your contours, whether attractive or not, is shown to full advantage.

Compression is meant to work by stabilising muscles and improving oxygen and nutrient supply in the body’s blood vessels. The jury seems to be out on its effectiveness in boosting performance, though some sources say recovery after exercise is better.

Whether or not you’re looking for enhanced performance, the fact that the X-Bionic hugs the body allows its various channels and pads to stay in close contact with the body and help the garment work.

Its design is meant to keep you cool when you’re sweating and warm when you’re cool. Anyone who has stood on top of a mountain after a trek up there will know how quickly you start to cool down in a moisture-laden top.
X-Bionic says its 3D-BionicSphere system only starts cooling when sweating begins. Until then, it just insulates.

Turn the Trekking Summerlight inside out and its complicated structure is revealed. There are inner air channels of raised fabric on the chest, back and lower back areas. A honeycomb padding area on the shoulders is designed to keep you ventilated under rucksack straps. There are underarm sweat traps to stop perspiration dripping and cooling. The hip areas have AirDuct areas similar to the shoulders to cool under the rucksack hipbelt.

So how does this work as a package?

We used the Trekking Summerlight in a variety of conditions: warm days; cooler days; as a baselayer under a waterproof in wet weather and as a baselayer under a softshell on a cool, windy day. And it performed well.

We’d say the X-Bionic Trekking Summerlight is just a little too thick for the hottest summer days. But for anything less than that, we forgot about its presence, which is often the best thing you can say for a piece of outdoor kit.

A pet hate is having to regularly stop to layer up or layer off as you move up the hill and back down. On a cool, dry, windy day, we managed, in complete comfort, to complete an ascent and descent of one of our test hills without a single change. The Trekking Summerlight worked well at keeping us cool under a softshell, kept us warm in the wind on top of the fell and worked well as we came down.

No short-sleeved t-shirt is ever going to keep you completely warm in a stiff wind on a hilltop, but for our brief stay on the top, there was no shivery, clammy feel you might expect, and the rush to put on another layer.

Worn on its own on warmer days, the t-shirt was comfortable enough, with the padding and ventilation working well under rucksack straps and belt. Sweat was evident on the outside face of the t-shirt in the chest area, but the skin felt fine, with no clamminess.

The Trekking Summerlight also kept odour well under control; in fact it was non-existent. The X-Bionic top has SkinNODOR technology to inhibit bacterial growth. The t-shirt can be happily worn on successive days without you feeling too anti-social.

For warmer days, X-Bionic makes a cool range, and it also offers warm and XT-warm versions. The Trekking Summerlight slots into the second category up of four, which we figure makes it suitable for conditions such as summer days with moderately warm temperature, down to cooler autumn and spring days, stopping short of those cold, full-on winter trips.

The technology doesn’t come cheap, but the X-Bionic Trekking Summerlight is a t-shirt that will keep you cool, or warm, in a good variety of conditions. Once you register your purchase, you also get a two-year guarantee.

One point: the sizing is fairly small and, with the compression, we would recommend moving up one size from normal.

Comfort 31/35
Warmth/cooling 26/30
Odour resistance 12/15
Quality 8/10
Value for money 4/10
Total score: 81/100

Our Trekking Summerlight was provided by X-Bionic.