There is a relationship between breathing and heartbeat, breathing and motion of the body, heartbeat and emotion, and all this is music. The mind and body are making music all the time, but this is silent so is overlooked or misunderstood. When sick, the natural rhythms get disturbed, as the manifestations of illness are like noise, too loud to be ignored, and not taking the other instruments in the body into consideration. The sick body has been distracted, and often is aided by re-establishing the natural rhythms again. Since the natural rhythms are so tied in with emotion, breathing, and motion, dancing or singing or otherwise moving with the beat naturally puts these natural rhythms back into place.
Music is also a healing reminder in that it speaks to more comforting and secure times.
Where life presents discord, the tension and release within music give the listener or dancer the opportunity to release tension that otherwise would remain bottled up. Thus, those especially tense may dance with particular abandon, all of which has less to do with the music and dance than with the dancers tense day. Music that heals is music that pulls the body into its natural rhythms, and depending upon the age of the listener or affliction, this may differ. Empathetic musicians often sense the effect their work is having upon the audience, and adjust accordingly. Quite without words, music speaks a language that few misunderstand.