Cardiorespiratory interactions during and after poetry recitation

Abstract

Aims Objective of the two studies presented was to assess cardiorespiratory interactions (direct and aftereffects) during guided recitation of hexameter verse, as used in Anthroposophic Therapeutic Speech ATS. We hypothesized that recitation of old Greek poetry coordinates the oscillations of heart rate and respiration. Methods Twenty healthy subjects performed with an experienced therapist three different exercises: hexameter recitation, controlled breathing and spontaneous breathing following the same protocol. The pace of walking in exercises was set by an electric metronome. During each session, an ECG and the nasal/oral airflow were recorded simultaneously. Cardiorespiratory sychronisation was quantified by the index γ , which has been adopted from the analysis of weakly coupled chaotic oscillators. To assess aftereffects, seven subjects were tested with weekly repetitions of the above protocol. Hexameter recitation was performed for 6 weeks and spontaneous breathing for 3 weeks. Results Direct effects : All exercises were associated with an increase in the heart rate, whereas the heart rate always decreased after exercise as compared to baseline. Cardiorespiratory synchronisation was high after hexameter recitation ( γ =0.70), less after controlled breathing ( γ =0.57) and desynchronized after spontaneous breathing ( γ =0.15). Aftereffects ATS increased regular patterns in heart rate variations, which persisted at least for 15 min after exercise. In comparison to spectral parameters of heart rate variability, cardiorespiratory phase-locking patterns disclosed the effects of rhythmic speech exercises best and were more prominent after ATS. Conclusions Therapeutic recitation of hexameter verse generates a strong cardiorespiratory synchronisation during exercise. An increase in regular heart rate variation patterns is observed for at least 15 min after exercise. ATS thus positively affects autonomic regulation and enhances synchronisation and a temporal order of cardiorespiratory functions; the effects of this may be beneficial in the treatment of hypertension and stress-related conditions.