Some of the benefits of sex are linked to the 'loving relationship' bit though, so are mostly bypassed in our job, i.e. semen has an antidepressant effect when absorbed via the vagina, thus only in bareback; oxytocin release is normally through post-coital cuddles and bonding etc. etc.
Personally I do find that it relieves stress, but then I'm lucky in that I orgasm easily and often.