Calm music, such as classical or smooth jazz, has the potential to lower heart rate in heart disease patients, according to research in the Cochrane Database of Systematic Reviews. Patients with heart disease already experience anxieties and fears related to their disease, which can naturally elevate heart rate. Music has been shown in the literature to decrease anxiety and stress, not only for heart patients, but even among the population at-large. In studies conducted to date, the type of music used is often calming or tranquilizing like classical.
In research published in Heart journal, study investigators suggested that overall, the tempo (pace) of music had far more impact on heart rate than the actual type of music played. Depending on the tempo of music (whether fast or slow), music has the ability to stimulate (faster tempos) or slow down (slower music) the heart rate. Even in pauses during music, the calming effect is noticeable. For instance, techno would have the influence of exciting heart rate, while raga (Indian classical) or classical music would have the opposite effect.
Similar effects on heart rate were found depending on volume. The louder the music, the faster the heart rate; likewise, the heart rate slowed with lower volumes. In fact, in the Heart study, heart rates closely resembled the louder and quieter moments of classical pieces.
Music's impact on heart rate can translate to less stress, improved athletic capabilities as well as enhanced functional abilities in neurologically-disabled people, such as those who have had a stroke. In general, the physiologic impact of music may heighten a person's response on an emotional level to the music being played.
To date, researchers have had modest success in explaining how music affects people emotionally, via tempo and volume. But the question of why music affects us is still not yet totally understood.