I hesitated buying these because it was hard trying to figure out what material they would be. I was thinking almost like wind breaker material. Boy was I wrong. These are very similar in feel to the rest day joggers (my favorite) except they are ribbed. If I was being super picky, I would say they are SLIGHTLY thinner than the rest day, and maybe a little silkier feel, almost like a loose fitting bathing suit material feel...? I love them and I will be buying more colors.
For reference, I wear an xs in Athleta pants, a size 4 in lululemon (except a 2 in aligns) and I am a small in all BP leggings/shorts/joggers. I am 5’0, 125#. I do CrossFit, so I have thicker glutes/thighs.