Comparative Effects of Buddhist Chanting Forms on Resting Heart Rate and Heart Rate Variability: A Preliminary Study

Chanting is a common practice in Buddhism. Nevertheless, limited studies have reported the effects of regular Buddhist chanting on physiological responses. This preliminary study aims to investigate the long-term and acute effects of regular Buddhist chanting on resting heart rate (RHR) and heart rate variability (HRV) indices that indicate parasympathetic activities (RMSSD, pNN50, HF) and general autonomic activation (SDNN, total power) and whether the effects were associated with the forms of chanting: reading aloud and reciting. Thirty young adults were divided into three groups in a non-randomized study: chanting-by-reading-aloud (Rd-Cht), chanting-by-reciting (Rct-Cht), and non-chanting control groups. Before and after the eight-week chanting practices, the HR and HRV were quantified by electrocardiography during the three testing sessions of resting, vocalizing, and recovery. The measurements were also conducted with eyes closed and eyes open conditions in each session. After the regular practice period, the Rd-Cht group had significantly lower RHR with higher RMSSD and pNN50 than pre-practice, whereas the Rct-Cht group had significantly lower recovery HR than the RHR with a higher SDNN and total power. In contrast, the control participants had significantly higher RHR with a trend of lower resting RMSSD and HF-HRV after eight weeks. The RHR and resting HRV changes in the chanting groups were independent of eye conditions. The preliminary results suggested that different forms of regular Buddhist chanting may be linked with reduced heart rate in different physiological states. Such effects could be influenced by parasympathetic modulation, which is often associated with physiological well-being.