Classical beats and white noise: Unveiling the effect of different music characteristics on heart rate variability

AIMS: Low heart rate variability (HRV) is associated with increased morbidity and mortality in various health conditions. Music can enhance HRV, but it remains unclear which music characteristics are most effective. This study aimed to assess the impact of music genre, white noise, tempo, and personal music preferences on HRV. METHODS: In this single-blind, randomised, within-subject study, participants without atrial fibrillation or pacemaker dependency listened to three-minute fragments of white noise and four music genres (classical, rock, electronic and a personal music) in random order. Participants were randomised to a slow or fast tempo group. Heart beats were recorded using a smartwatch containing a photoplethysmography (PPG) sensor; non-sinus beats were excluded using a custom algorithm. HRV was analysed using a general linear mixed model adjusted for heart rate, sex, age and tempo, with interaction analysis for tempo effects. RESULTS: A total of 242 participants were included. White noise was associated with the highest HRV across all tested metrics: standard deviation of normal-to-normal intervals (SDNN), root mean square of successive differences (RMSSD), low-frequency power (LF), and high-frequency power (HF). Furthermore, HRV (RMSSD) was higher during classical music compared to electronic and personal music (P = 0.025 and P = 0.030). Interaction analysis showed the latter was due to differences only in slow music tempo. CONCLUSION: Slow, classical music enhances HRV more than electronic or personal music, suggesting its therapeutic potential. Remarkably, white noise showed the greatest increase in HRV compared to all music genres, possibly due to its consistent and monotonous sound characteristics inducing a relaxation response and increased parasympathetic activity.