Last updated: 17-Aug-18
Whether you wear it for the entire run, put it on at the start when it’s chilly and take it off when you warm up, or pop it on at higher altitudes, there is little doubting the value of a long-sleeved baselayer or mid-layer. A baselayer is also useful year-round and, for many ultra runners, a favourite extra layer will be with them for years.
On test are the Helly Hansen Active Flow LS baselayer and Inov-8 hooded AT/C Merino Long sleeve mid layer.
Helly Hansen Active Flow long-sleeved layer
A mainstay of many outdoorsy people’s wardrobes, the HH brand has also become popular among runners, too.
Photo credit: Hellyhansen.com.
- Long sleeved and crew neck
- Lifa® Flow technology
- Lifa® Stay Dry technology
- Polyester exterior
- Flatlock stitching
- Relaxed fit
- Designs for men and women
- Weight: 130g/m²
I have owned a HH baselayer or two in a range of designs for almost all of my adult life. I like the fit and shape. The Active Flow is a more relaxed style and has longer arms than normal, which I appreciate.
The design is always recognisable with the white and coloured stripes. Over the years HH has sold a wide range of colours and designs. If you want to pay a bit extra, you can get a version of this top with graphic design.
The fabric is soft and smooth and very easy to wear against the skin. I know that Merino products are often more insulating and boast natural anti-bacterial properties but I do not like wearing them against my skin because I find they itch.
The problem with HH baselayers is they do tend to smell after just one wear. They are known in my world as a “smelly Helly” but that is combatted by washing the top after each wear. (I use a sports wash product for best results.)
I always choose a HH baselayer or a similar type of product made by inov-8 over a Merino wool top because I know it will be so comfortable.
It’s the kind of top I’d wear as a mid-layer in winter, under a windproof or waterproof jacket, and as an outer layer in the summer when needed. It’s a layer that I always carry as a spare in my running (and walking) rucksack.
The polyester dries very quickly even when I sweat hard and the fabric is highly breathable. It’s lightweight and squashes into the smallest of corners in a rucksack or even a jacket pocket.
The baselayer is crew neck and does not have a half zip or any added features.
A Helly Hansen lasts for many years so they are good value for money.
PROS: Soft against skin; lightweight; quick drying; fit; style; durability.
CONS: Odour from sweat; no frills.
Helly Hansen is my go-to baselayer for lightweight insulation. It is easy to wear and while the armpits do end up being quite whiffy after one wear, I prefer the polyester fabric to Merino, which makes me itch. The price is good.
inov-8 hooded AT/C Merino Long sleeve mid layer
inov-8 make clothing specifically for runners and have a reputation for thinking of all the small details. The hooded AT/C Merino long sleeve mid layer offers versatility when the weather looks changeable.
Photo credit: inov-8.com.
- 96% Merino Wool / 4% Lycra to help regulate core body temperature
- Superfine 18.5 micron Australian merino wool
- Thumb loops and cuffs that adapt into hand mitts
- Hood for added warmth and protection
- Front chest zip for warmth or ventilation
- Weight: 222g (medium women’s) to 263g (medium men’s)
- Price: £90
- See Inov-8
Merino wool is undoubtedly a great product for regulating body temperature. It’s a natural material that insulates but also offers great breathability and wicking. Merino wool is usually quick drying, too.
All these benefits are found in the inov-8 hooded AT/C Merino long sleeve mid layer. The fit is also lovely. It is not too tight but also not too loose.
The length of the torso is generous and the arms are long so that you can turn over the cuff mitts if you need them. This is really useful for someone like me who gets cold hands all of a sudden.
The hood fits neatly, especially when the zip is done up and this means you can wear it while running and without the wind catching it.
Many people will find they can wear the soft merino wool against bare skin but I still find even this quality itchy. It’s better than many I have tried but I would need to wear a long sleeved polyester baselayer underneath it. This is probably just my sensitive skin.
The jacket comes in black only, which is a bit dull in my opinion. I’d prefer a brighter colour or at least a top with reflective detailing. I rarely choose black for running kit, especially if I’ll be out running in winter.
Photo credit: Fiona Outdoors.
PROS: Nice design features; hood; cuff mitts; soft merino.
CONS: Itchy for some; pricey; only one colour.
inov-8 make good quality and durable products with lots of nice details. This is a well thought out mid-layer but I do think its quite pricey and it comes in only one colour.
About the writer: Fiona is a keen runner, preferring off-road and hilly to flat and road. She lives in Scotland where the weather is fickle so needs to be prepared for all conditions.
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