Take one size up due to tight fit, I wear L but because I had a bad experience with a similar product from another brand, I ordered XL in this one.
I bought 3 pairs and took them to the tailor for 2 fingers shorter sleeves and 4 at the waist, and that's it.
They keep me warm (I eat cold from a double door that opens and closes), they don't bother me in arm-waist movements, they absorb sweat after walking.
Thanks to this shirt, I no longer need short-sleeved or sleeveless sweaters, etc. for the cold, I am very satisfied!