Lumma, A. L., Kok, B. E., & Singer, T. (2015). Is Meditation always relaxing? Investigating Heart Rate, Heart Rate Variability, Experienced Effort and Likeability during Training of three types of Meditation. International Journal of Psychophysiology. Accepted manuscript in press. From the Abstract.
Meditation is often associated with a relaxed state of the body. Meditation can however also be regarded as a kind of mental task and training, which is associated with mental effort and physiological arousal. The cardiovascular effects of meditation may vary depending on the type of meditation, degree of mental effort, and amount of training.
In the current study we assessed heart rate (HR), high-frequency heart rate variability (HF-HRV) and subjective ratings of effort and likeability during three types of meditation varying in their cognitive and attentional requirements, namely breathing meditation, loving-kindness meditation and observing-thoughts meditation. In the context of [this] project, a one-year longitudinal mental training study, participants practiced each meditation exercise on a daily basis for 3 months.
Results showed that as expected HR and effort were higher during loving-kindness meditation and observing-thoughts meditation compared to breathing meditation. With training over time HR and likeability increased, while HF-HRV and the subjective experience of effort decreased. The increase in HR and decrease in HF-HRV over training was higher for loving-kindness meditation and observing-thoughts meditation compared to breathing meditation.
In contrast to implicit beliefs about meditation being always relaxing and associated with low arousal, the results show that core meditations aiming at improving compassion and meta-cognitive skills require effort and are associated with physiological arousal compared to breathing meditation. Overall these findings can be useful in making more specific suggestions about which type of meditation is most adaptive for a given context and population.