I was knickers shopping last week and looking for some nice comfortable, cotton knickers that would not ride up and not show under my sports leggings. There was a range of supposedly "invisible" underwear available. Supposed "boy shorts" where the leg was cut off so high, the seam would be completely visible and the wedgies continual. (I know because I was wearing a pair at the time.) There were seamless knickers that I know don't sit smoothly with movement. And a number of thongs, which just aren't always comfortable during sports/exercise. All of the first two types, and most of the thongs were also made of some sort of unnatural material which is horrible sweaty with even mild activity.
I was feeling annoyed and wishing I could just but something like the proper undershorts my 7yo DS wears, when I realised that I actually could! I headed off to the men's underwear and found some nice smooth shorts, 100% cotton, long enough on the legs to not be visible. I made sure that they didn't have an opening at the front and bought a pack. I have pretty big hips and bum, so I wasn't sure how they'd work but thought it would be worth a try.
Well, this week has been great! No knickers up my bum. No VPL. No horrible sweat build up at the seam between my crotch and thighs. Yes they are a tiny bit loose right at the crotch but not in anyway that is bothersome. I suspect that with a few wears and washes, they'll sit better on my shape and be even more comfortable. I plan on getting some more and eventually replacing almost all my knickers with men's shorts.