According to the gate-control theory, a back massage would most likely reduce your physical aches and pains by causing activation of nerve fibers in your spinal cord. the cochlea to transduce impulses sent to the spinal cord. deactivation of the pain receptors on the surface of your skin. release of pain-killing endorphins in your muscles. the release of adrenaline into your bloodstream.

by causing activation of nerve fibers in your spinal cord

Explanation:

According to the gate-control theory, a stimulation of other nerve fibers, which are nonnociceptive fibers in the spinal cord, via massage, would override nerve fibers that transmit pain signals by nullifying the effect or close such gates which inhibits its effects. When this occurs, the amount of pain signals reaching the brain is diminished as large nerve fibers are stimulated via back massage.

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