From a study by L Bernardi, C Porta1, and P Sleight:
Even short exposure to music can induce measurable and reproducible cardiovascular and respiratory effects, leading to a condition of arousal or focused attention that is proportional to the speed of the music and that may be induced or amplified by respiratory entrainment by the music’s rhythm and speed. This effect is independent (at least under the experimental conditions of our study) of a person’s preference or of repetition and habituation [emphasis added], and is clearer when the rhythmic structure is simpler. This was perhaps less evident in non-rhythmic or syncopated music. A pause in the music induces a condition of relaxation greater than that preceding the exposure to music and leads to the speculation that music may give pleasure (and perhaps a health benefit) as a result of this controlled alternation between arousal and relaxation. It may be viewed as an alternative technique of relaxation or meditation, without involving the active participation of the subject. Previous training in music enhances the subject’s ability to respond to music rhythm [emphasis added], since musicians learn to synchronise breathing with the music phrase. In conclusion, the present study indicates that appropriate selection of music, by alternating fast and slower rhythms and pauses, can be used to induce relaxation and reduce sympathetic activity and thus may be potentially useful in the management of cardiovascular disease [emphasis added].
[In the full paper, musicians were consistently found to have lower baseline respiratory rates, meaning that they take fewer (and by logical extension, deeper) breaths per minute. My own breathing averages about 2-3 breaths per minute when resting.]
The study authors have found that classical music lowers stress levels and therefore promotes respiratory and cardiovascular health, by providing relaxation. Therefore, even a few minutes’ exposure to classical music will help your overall heart rate, blood pressure, and your sympathetic nervous system. So change your radio station and reap the benefits!