Last week, my family and I went on a skiing holiday.
Some weeks ago, we went out and bought all the jackets, trousers/salopettes, and thermal base layers.
The base layer consists of a close fitting, long sleeve shirt and long-johns.
I have to say, that the long-johns were terrible. To get the length of leg, I had to buy a size which had a huge waist. This made them really uncomfortable, and I felt like I'd always be pulling them up.
So, a week or two before we went, I bought some thermal leggings for my waist size, with a "long" leg. They fitted perfectly and were much more comfortable. Furthermore, they were warmer than ones which were designed for skiing. This was quite important because where we were skiing, the daytime temperatures were often around -10 Celsius (about 14 Fahrenheit).
So I spent the week with leggings on under my salopettes. My wife had no idea that they were not the skiing long-johns, and never said a word, because they looked almost exactly the same. Interestingly, unlike most womens' clothes, the leggings were labelled as "large" rather than as a dress size, so even that won't be a giveaway if my wife happens to see the label when she washes them.
It's funny how two almost identical products (except for the waist size) can be marketed and sold to men or women as ski base layer, but if they are sold as leggings they immediately become women only, yet a woman who wears leggings frequently did not notice the difference.