Abstract
BACKGROUND: In previous studies, we showed that laser needle acupuncture with red and infrared light has specific effects on bio-signals of the brain and heart. AIMS: In this publication we report the effect of blue laser light on heart rate and heart rate variability (HRV) before, during and after acupuncture at the acupoint Neiguan (Pe.6) in Chinese adults. These are the first data published concerning heart rate and HRV, obtained with blue laser acupuncture equipment. PATIENTS AND METHODS: The investigations were carried out in 13 healthy Chinese volunteers with a mean age of 31.2 ± 7.5 years within a randomized, controlled study. Stimulation was performed with painless blue laser light (wavelength: 405 nm; activation: 10 minutes) bilaterally at Pe.6. In a second session, for control reasons the laser was not activated. RESULTS: Heart rate showed a significant (p=0.008) decrease during blue laser light stimulation. In contrast, no significant changes were found when the laser was deactivated. The evaluation parameter LF/HF ratio (low frequency/high frequency ratio) from the HRV spectral analysis showed a very slight increase during stimulation, however it was not significant. CONCLUSIONS: Our main conclusion is that continuous blue laser light stimulation on Neiguan significantly reduces heart rate of Chinese adults.