That kind of thing makes me wonder how likes of Katja, Bobbi Starr and (retired) Luscious Lopez do scene after scene of anal with no apparent issues, Lopez's butthole looked as good as the day she started I think.
Luscious Lopez's butthole, indeed her entire physique, looked great all along. Different people's rectal anatomy responds differently to sodomy. For example, I got through eight years of the Navy without much difficulty.