The effect that music has on the human body could be used as an alternative form of therapy, research suggests.
A study from the University of Pavia, Italy, found random classical tracks affected the heart, arteries and lungs; crescendos increased blood pressure and heart and respiration rates, while relaxing passages did the opposite.
Study leader Professor Luciano Bernardi said: "Music induces a continuous, dynamic and, to some extent, predictable change in the cardiovascular system.
"The profile of music (crescendo or decrescendo) is continuously tracked by the cardiovascular and respiratory systems. This is particularly evident when music is rich in emphasis, like in operatic music. These findings increase our understanding of how music could be used in rehabilitative medicine."
Half of the 24 volunteers involved in the research, published in Circulation, the journal of the American Heart Association, were trained singers and half had no musical experience.
The group was played music including Beethoven's Ninth Symphony, an aria from Puccini's Turandot, a Bach cantata, "Va Pensiero" from Verdi's opera Nabucco, and "Libiam Nei Lieti Calici" from Verdi's La Traviata.
The blood vessels of volunteers were also found to dilate and their heart rate and blood pressure reduce when they listened to a two-minute silent pause.
Musical phrases around 10 seconds long became synchronised with heart and blood circulation rhythms, the researchers found.