I did a google image search on both of these but came up empty.
The first pic one of our members uses as a profile pic. I sent a private message to that person but that person hasn't replied yet. Nothing came up on the google image search; I don't know if the image is too small to do a search on, but given that the person is a member here the person likely got the image here. She's wearing (nothing but) running shoes, so maybe it's a naked run (checked the last two years of that thread) of some type.
The second one I came up empty too. Just seeing if anyone recognizes that nice round behind from somewhere.
Thanks!