I recently got into a discussion of why some of us enjoy massage so much related to hormones.
My favorite activity is the nude-reverse (NR) massage parlors of Mississauga. NR is on the public website menus of zillions of adult massage parlors, thanks to Ms. Hazel, who for decades as mayor into her 90s. I wish in the U.S. we would adopt the harm reduction model of Canada vs. the legal status resulting in going after consenting adults which increases the potential for harm.
My favorite adult activity is massage, giving as well as receiving with an attractive naked woman experienced in sensuality (not just sex), and the positive reaction I usually get. I also enjoy contact lap dances at strip clubs (especially in Canada) and the often positive response to caring touch. I've been trained in Esalen, taught couples classes, and have a 10-minute routine for the nude-reverse parlors, which I call more caring, heartful loving touch - very nicely sensual but not directly sexual (no penetration).
There is a scientific reason we enjoy caring touch done by someone we trust. The trust is usually established quickly by the right kind of touch - not groping and grabbing as I am told lots of men do.
Dogs (bow wow kind)
While I prefer an attractive woman, it is the same principle why therapy dogs are becoming popular or why we enjoy petting a dog or cat.
Dogs have been used to help stress in long lines at airports and recently been allowed to sit next to children testifying about sexual abuse. When the dog senses stress (cortisol hormone), it nudges the person, and the dog wants to be petted. It has been shown that the petting then releases oxytocin in the human. Most dogs like petting. Most women or men, like to be lovingly massaged or caressed. Cuddling with an adult companion is also one of my favorite sports and legal even in the U.S.
While human contact with a woman (for us straight men) is far nicer for most of us than a dog, the science is similar. It generates the calming feel-good hormone oxytocin which adds to the enjoyment of "sensuality."
In stress situations, a therapy dog has very sensitive smell for human cortisol which is the stress hormone when we are under stress. Dogs can also detect low blood sugar levels in diabetics and often have warned their humans to wake up or amazing other things, even detecting cancer in some patients and even if not trained can act alarmingly - pawing - on a part of the body that has cancer growing.
In stress situations (waiting long lines at an airport or testifying in court about sexual abuse, for example), oxytocin counteracts the cortisol. But even without stress, it can be released as in nice massage or just when petting a dog or cat.
Medically, the peptide hormone oxytocin is produced in the hypothalamus and released into the circulatory system and the brain in response to sensory stimulation via a network of OT-containing nerves.