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There’s a special kind of painful pleasure that comes from a good back rub. Massage specialists and friends alike spend a lot of their time balancing the pain that comes with squeezing and pressing your aching back with the pleasure that comes when that pressure is off. But why are back rubs so great? Why aren’t we all crazy for stomach rubs or ankle rubs?

No one knows for sure. But Real Clear Science explains one idea:

Last year, researchers at UC – San Diego examined the affect of a fifteen-minute back massage on hormone levels in the body. The participants who received a back rub were found to have significantly higher levels of oxytocin compared with control subjects who merely rested quietly. The hormone is known to evoke feelings of contentment and alleviate feelings of stress and anxiety.  Additionally, the researchers found that levels of corticotropin, a hormone associated with biological stress, were reduced. Contrary to the earlier mentioned endorphin theory, they also discovered that the experimental group had lower levels of beta-endorphins.

Another theory has to do with how quickly signals like pain and pleasure travel through our bodies. A review paper explains:

Melzack and Wall (1965) theorized that the experience of pain can be reduced by competing stimuli such as pressure or cold, because of the fact that these stimuli travel along faster nervous system pathways than pain. In this way, [massage therapy] performed with sufficient pressure would create a stimulusthat interferes with the transmission of the pain stimuli to the brain, effectively “closing the gate” to the reception of pain before it can be processed.

Another theory for why back rubs are great, is because they take us back to when we interacted, physically, in groups all the time. Here’s the American Chemical Society’s blog:

But in our own modern “rat race”society, have we humans lost the need for touch? Not at all, according to pediatric psychologist Tiffany Field of the Touch Research Institute. Field, who does most of her research at the University of Miami, says humans can suffer health setbacks without touch and gain health benefits with touch. Her studies show that, in addition to relieving a sore back, massage can relieve anxiety, depression, tension, and stress; help with headache, chronic pain, and digestive disorders; and encourage healing of almost any area in the body by promoting the flow of blood and lymphatic fluids, stimulating nerves, and loosening muscles and connective tissue to keep them elastic.

So get ready to start rubbing, because back rubs, for whatever reason, aren’t going to stop feeling good any time soon. And in case you’re bad at them, here are some pointers.

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