The North Face Isotherm 1/2 Zip Review

The following review was included in Issue 10, Autumn/Winter 2013 of Barefoot Running Magazine.

The North Face Isotherm ½ Zip Shirt arrived with me just in time for the drop in temperatures that heralded the end of a brilliant summer and, since that point, it has been in constant rotation, having been worn not just for running but for anything and everything from hiking and biking to general everyday use.

The Isotherm, billed as “an innovative hybrid trail running top designed for protection and warmth,” is available in both men’s and women’s styles and is definitely worth a look if you are considering what to wear to see you through the Autumn and Winter months.

When it comes to the worst of the Autumn/Winter weather, most notably the snow and rain, the Isotherm will be paired up with a breathable waterproof layer to add that additional element of protection. At the time of writing I haven’t yet had the opportunity to test the Isotherm in extreme cold but, from the forecast, it would appear that I will not have to wait too long to be able to do this!


The Isotherm ½ Zip Shirt comes in Nautical Blue/Estate Blue or TNF Black/Asphalt Grey colour combinations.


The Isotherm offers a really comfortable fit, neither overly large nor overly tight. My standard XL size provided the perfect fit and it was as comfortable sitting at a desk as it was out on the trail. The only potential issue would be with regard to the sleeves which, with their built in mitt protection, are slightly longer than standard sleeves. However, the mitt element can easily be folded up into the sleeve.

Build Quality

As you would expect from The North Face, the quality of the garment is excellent, well constructed with neatly stitched seams and good attention to detail. Despite repeated washes over the short time that I have had the Isotherm, it shows no sign of degradation at all.

The Isotherm uses proprietary fabrics developed by North Face, including FlashDry™, which incorporates microporous particles to improve moisture management and temperature regulation during outdoor activity. FlashDry™, used across a wide number of products in The North Face range, accelerates the removal of moisture from the skin, enabling the user to stay drier and more comfortable for longer. FlashDry™ is permanently embedded in the yarn and won’t wash out.


The Isotherm ½ Zip is part of The North Face’s Flight Series running collection, athlete tested and competition proven, and, as such, you have high expectations for the garment.

The Isotherm consists of a wind resistant core which blocks the wind and helps to retain heat, with a wool blend on the sleeves and FlashDry™ paneling for ventilation on the sides of the garment, down the back, and under the arms.

The built in sleeve mitts can be folded up inside the sleeve or simply rolled up around the wrists when not in use. However, chances are you are going to want to make use of the hand protection afforded by these, especially in the chillier temperatures. They are no substitute for gloves in really cold temperatures but are certainly useful on those days when gloves would be overkill and result in overly hot hands.

The double zip used in the ½ zip neck is one area where the attention to detail is evident. I actually overlooked this feature at first, not appreciating just how useful the double zip could be. It facilitates optimum control over ventilation, enabling full coverage when zipped up, ample ventilation when zipped down, or a combination approach if the bottom zip is used. Zipping up from the bottom permits easy ventilation of the chest area without the need to leave the neck flapping around, a useful feature for those days when the winter sun heats you up.

The neck of the garment has a cover to prevent the zip from rubbing against your skin.

There’s a useful zipped chest pocket that’s perfect for holding a key or a lightweight MP3 player.

360 degree reflectivity is provided as a result of reflective logos and use of reflective trims, with the traditional The North Face logo on the front, and a Flight Series logo on the rear of the garment.

I was initially quite surprised at the combination of materials on the Isotherm. The shiny core seemed at odds with the wool blend sleeves and FlashDry™ paneling. However, having tested the Isotherm in a variety of scenarios, I can see how well the separate elements work to provide the perfect conditions for running.


RRP £85.00

Overall Rating

The Isotherm ½ Zip Shirt certainly ticks all the boxes if you are looking for a top that offers wind resistance, temperature regulation, breathability and comfort. It’s the quality product that you would expect to come from The North Face and the combination of a wind resistant core and FlashDry™ paneling results in a garment that doesn’t leave you chilling in your own sweat. The double zip and built in mitts are useful additions to the garment, adding to the overall functionality. Definitely a garment worthy of consideration if you are looking for something to see you through the colder months.



  • Two-way zip
  • Reflectivity at zip
  • Shaped hem
  • Thumbholes
  • Secure chest pocket
  • Reflective logo
  • Fabric
  • body: 200 g/m2 56% merino wool, 37% polyolefin, 7% polyester knit
  • panel: 76 g/m2 100% polyester woven

Columbia OMNI Freeze Review

The human body uses sweat to let heat escape from the body and, in doing so, attempts to prevent us from overheating. Sweating can range from the effective ‘glow of perspiration’ to the ‘dripping’ stage, where the body is battling to control its temperature. Unfortunately, as one of life’s larger runners, I tend to find myself at the dripping end of the scale more often than not. It’s not a comfortable place to be, especially when exerting yourself for any length of time. I’m sure many of you will have experienced that really uncomfortable moment when you put a rucksack back on to an already sweaty back. Clothing manufacturers have attempted to address the problem, with varying degrees of success, by producing clothing that wicks the sweat away from the body. Most manufacturers have adopted the same approach, viewing sweat as a problem, something that needs to be removed. Columbia have turned this approach on it’s head with their range of Omni-Freeze Zero products, t-shirts, shorts, and accessories that actually seek to put your sweat back to work. When I first heard about this, I will admit to being sceptical but I was fortunate enough to receive an Omni-Freeze Zero t-shirt to test and, I have to admit, by the end of testing I was suitably impressed.

The Technology

Omni-Freeze Zero technology is intended for running and other fast paced activities. The tshirt material contains visible blue rings of cooling polymer and it is these rings that create the cooling effect. When exposed to moisture, the rings swell, letting air pass around you as if you had goosebumps, resulting in the cooling sensation. Given that my tshirt was the same blue colour, I hadn’t actually noticed the composition of the fabric but, as my run progressed, I could see more and more of the rings contained in the fabric. When you stop sweating, the material soon dries, and the cooling effect stops. As such, you should never find yourself getting too cold. Columbia are so confident of their product that they believe it’s cooler to wear an Omni-Freeze Zero top than taking your top off entirely. According to Columbia, the cooling effects will last for the life of the garment.

The Test

Scotland has actually seen some consistently hot weather for the first time in years (to the point that people were actually starting to complain about the heat – what’s that about!) It gave me the perfect opportunity to try out the Columbia Omni-Freeze Zero tshirt. Not only did I test it out and about on the roads and trails. I put it to the ultimate test, running on a treadmill at midday in the sun-trap conservatory at the back of our house where the temperature hit 30C!. I’ve never been a fan of running in the heat, largely due to my bulk, but this year I was determined to do something to address this, and I was taking the Columbia Omni-Freeze Zero shirt along for the ride! The tshirt offers UPF50 sun protection, is antibacterial, and has ergonomic seams, for comfort on the move. I found it to be form fitting, not as loose as I would normally wear my tshirts but, thankfully, not overly tight as required by some wicking garments for full functionality. So, how did it fare? Well, I actually felt nothing, but in a good way, if that makes any sense at all! I end up pretty sweaty at the best of times, with my tshirt clinging uncomfortably to me, and that’s in normal temperatures, not the summer temperatures experienced these past few weeks. However, when wearing the Columbia Omni-Freeze Zero tshirt, I found that my upper torso was some kind of neutral zone – I was never too hot or too cold. I just didn’t have to give any thought to my temperature, leaving me to focus my attention on the run in hand. What was surprising was the extent of how wet the tshirt was by the end of my exercise, and, perhaps more surprising, that I hadn’t noticed this whilst wearing it. Going by the success of my experiment, it’s definitely time to invest in some more of the Omni-Freeze Zero tshirts. I’m also keen to try the Omni-Freeze Zero bandana. If it’s anywhere near as effective at cooling as the tshirt, it will soon replace my standard Buffs as my favoured headgear for running. Update 26th August 2013: Given the success of the aforementioned testing, I packed the Columbia OMNI Freeze for a holiday in the Scottish Cairngorms, where I knew I would be doing a fair bit of running. The weather overall wasn’t too bad for August and certainly far better than I have experienced in the past at that time of year. However, there were a few days with some significant wind, especially as my runs took me higher up into the mountains. Two days in particular stand out, where I was being blown left, right and centre by the wind, to the point of making little headway. However, the Columbia OMNI Freeze kept me from feeling the worst of the chill, despite being soaked in sweat from my exertions. Again, very impressed and glad to have packed the OMNI Freeze for runs up into the mountains. RRP: £35


  • Weight: 135g (men’s medium)
  • Fabric: Omni-Shade, Omni-Freeze ZERO, Omni-Wick 92% polyester/8% elastane ZERO jersey
  • Sizes Available: S-XXL
  • Colours: Wham (green), Black, White, Hyper Blue


Columbia – Trying stuff since 1938: Columbia Omni-Freeze Zero Explanation: There’s also a ‘slightly’ tongue in cheek video to promote the Omni Freeze Range:

Helly Hansen Dry Revolution LS Review

Base Layers

A base layer is generally a figure fitting garment that is used to help regulate body temperature, keeping you warm in cooler conditions and cool when in hotter conditions. Because of the close fitting nature of the garment, moisture and chafing are eliminated, resulting in greater comfort and enjoyment whilst undertaking your activity. Typically, base layers are worn next to the skin though they can also be layered if conditions dictate, trapping heat between each layer. Base layers offer an element of breathability and wick away sweat from the body, effectively keeping you both warm and dry. This is where they come in to their element and is what makes a base layer far more effective than your typical t-shirt.

“You can have the world’s most expensive Gore-Tex jacket, but wear a cotton t-shirt underneath and you may as well be wearing a bin-bag for all the benefit you’ll feel” (

The 2 Main Functions

  • Remove sweat/moisture
  • Provide insulation as a result of trapping air next to the skin

“When you’re working hard, your base layer is removing sweat from your skin cooling you down, and when you’re cool (and therefore not sweating) the trapped air is keeping you warm.” (

Helly Hansen Dry Revolution Review

Despite the obvious benefits of using a base layer, it’s not something that I have embraced. For one, they are far from flattering to my less than Adonis like figure. Admittedly, at this time of the year, that’s not such an issue as I can hide my embarrassment underneath a secondary layer. However, I have in the past found base layers to be somewhat claustrophobic (Think Han Solo being encased in carbonite in The Empire Strikes Back for comparison!). I have just never been a fan of that uncomfortable, restricted feeling that accompanies donning a base layer.

However, towards the end of last year I was fortunate enough to have the opportunity to test the Helly Hansen Dry Revolution long sleeve base layer and my experiences have been far more positive, to the point, in fact, that I am loathe to take the thing off!

Slipping the base layer on, I didn’t actually feel too bad. There was a brief feeling of tightness as I got used to having the garment on but this could best be described as fleeting and was followed by a pleasant feeling of warmth. Given the poor weather of late, this has been a godsend!

So far, I have tested the Dry Revolution of medium length runs in and around Ellon, my local ‘stomping grounds’, and, more recently, in the Cairngorms where the conditions were ‘challenging’ with snow showers, sub zero temperatures and high winds.

The first run in the Dry Revolution was enlightening. Normally, wearing a typical running t-shirt, I experience awkward moments where the wet t-shirt comes into contact with the skin, a far from pleasurable feeling. There was no such feeling with the Dry Revolution, even when removing my running pack and putting it back on. In fact, by the time I got back from that first run, feeling dry and warm despite the wet and windy conditions, I was actually shocked to find that the garment was soaked through with sweat.

On a number of runs I have teamed the Dry Revolution with my new lightweight, breathable Montane Minimus waterproof and the combination has coped really well, especially most recently in the challenging conditions of the Cairngorms. Despite the extra effort expended on ascents and descents, I have returned from runs feeling similarly dry and warm.

The only ‘problem’ with a garment this effective is at the point when you have to remove it, which left me feeling like all the warmth had been ‘sucked out of me!’

So, a huge thumbs up from me for the Helly Hansen Dry Revolution LS and definitely a garment that I will be wearing for the foreseeable future.

I just need to work on those abs so that I can pull off wearing a base layer in the summer!


The HH®Dry™ technology behind the Dry Revolution is described as a “moisture super highway creating a dry layer next to the skin, keeping you comfortable during highly aerobic activities in a wide range of conditions”.

“With long sleeves for warmth and all-over wicking power, this baselayer has everything you need for maximum comfort. The HH® Dry Revolution fabric is made from new Lifa® fibres that are even softer and more effective at drawing excess heat and sweat away from your skin, allowing you to maintain an optimum body temperature throughout your activities. It has a minimum of seams, sewn with flatlock stitching for a smooth look and feel, inside and out. Lifa® stripes add a splash of colour to the lower sleeves.”