Wool has a reputation for being itchy, but the issue comes down to the thickness of its fibres. Traditional wool contains coarse fibres that feel prickly against the skin, while fine merino fibres are thinner and more flexible, making them comfortable enough for next-to-skin performance apparel. The difference comes down to micron count.
Micron count explained
Fibre fineness is measured in microns. The lower the micron count, the finer and softer the fibre.
Traditional coarse wool measures around 30 microns or more, while performance-grade merino ranges from 17 to 19.5 microns.
At this fineness, merino fibres are flexible enough to bend against the skin instead of pressing into it. This reduces the prickly sensation associated with coarser wool and gives fine merino its characteristic softness.
Why some merino garments still feel itchy
Micron count is not the only factor that determines how merino feels against the skin. Fabric construction also plays an important role.
A garment made with coarser fibres or a rougher knit structure feels less comfortable against the skin, even when it contains merino wool. The quality of the fibre and the way it is constructed into fabric both contribute to the final feel of the garment.
This is why two garments made with merino wool can feel very different against the skin.
Why this matters to Athlos
At Athlos, we use fine merino because it feels buttery-soft and cozy against the skin.
But comfort is only the starting point.
Merino is naturally odour-resistant, moisture-wicking and thermoregulatory, making it well suited as a high-performance fabric. As a natural fibre, it also aligns with our sustainability goals.
That’s the Athlos way: choosing smart fibres that bring together comfort, performance and sustainability.
Frequently Asked Questions
What micron count is best for sensitive skin?
Look for merino wool in the 17–19.5 micron range, which is fine enough to bend rather than poke against skin — this is the standard range used in performance running apparel and is far softer than traditional coarse wool.
Is merino wool too hot to wear in warm weather?
No. Merino's hollow, crimped fiber structure regulates temperature in both directions, helping release excess heat and moisture in warm conditions rather than trapping it like a thick sweater would.
Can you wear merino wool in summer?
Yes. Lightweight, fine-micron merino performance fabric is well suited to summer running because it manages moisture and odor effectively even in heat and humidity, unlike traditional heavyweight wool garments.
How do you wash merino wool without damaging it?
Wash on a cold, gentle cycle with a wool-safe detergent, skip fabric softener, and lay the garment flat to dry rather than using a tumble dryer, which causes shrinkage over time.
