The Dosage Effect of Laser Acupuncture at PC6 (Neiguan) on Heart Rate Variability: A Pilot Study

Abstract

Laser acupuncture (LA) has been more applicated in the clinical practice with good responses, but the dosage and parameter settings are still inconsistent with the arguments. This study is focused on the effect of LA on heart rate variability (HRV) with different energy density (ED). Based on the Arndt–Schulz law, we hypothesized that the effective range should fall within 0.01 to 10 J/cm2 of ED, and settings above 10 J/cm2 would perform opposite or inhibitory results. We recruited healthy adults in both sexes as subjects and choose bilateral PC6 (Neiguan) as the intervention points to observe the HRV indexes changes by an external wrist autonomic nerve system (ANS) watch on the left forearm. The data from the ANS watch, including heart rate, blood pressure, and ANS activity indexes, such as low frequency (LF), high frequency (HF), LF%, HF%, LF/HF ratio, and so on, were analyzed by the one-way ANOVA method to test the possible effect. In this study, every subject received all three different EDs of LA in a randomized order. After analyzing the data of 20 subjects, the index of HF% was upward and LF/HF ratio was downward when the ED was 7.96 J/cm2. Otherwise, the strongest ED 23.87 J/cm2 performed the opposite reaction. Appropriately, LA intervention could affect the ANS activities, with the tendency to increase the ratio of parasympathetic and decrease the ratio of sympathetic nerve system activities with statistically significant results, and different ED interventions are consistent with Arndt–Schulz law with opposite performance below and above 10 J/cm2.

The effects of laser acupuncture dosage at PC6 (Neiguan) on brain reactivity: a pilot resting-state fMRI study

“…Our study diverges from this trend by recruiting individuals from the general population and investigating the potential physiological follow-up effects resulting from stimulation of different EDs, an area that has received comparatively little attention. Our achievement is not only consistent with the usage methodology and parameter settings recommended by prior related journals ( Huang et al, 2009 ; Zein et al, 2018 ; Cronshaw et al, 2019 ; Chang et al, 2022 ), but also carries implications for the safety of LA application and the varying biological effects resulting from distinct dosages. Our findings provided a valuable foundation and reference for operators and researchers in developing future treatment strategies or research designs.…”

“…This omission is primarily due to this study’s reliance on established empirical medical research findings, and it is deemed unnecessary to reiterate the impact of RVLM on the SNS and BP. Our team’s preliminary research already exhibits that distinct EDs can produce varying degrees of impact on the ANS ( Chang et al, 2022 ), exhibiting a biphasic dose–response phenomenon. The primary aim of this study is to employ this premise as a means to investigate alterations in the FC between relevant brain regions in response to varying EDs of LA.…”

“…For example, some studies have pointed out that LA tends to increase sympathetic and inhibit parasympathetic nerve activities in patients with insomnia ( Chen et al, 2019 ), but others have found the opposite performance in LA interventions for night shift worker groups by different LA intervention and parameter settings ( Wu et al, 2009 ). Previous research conducted by our team has demonstrated that LA can effectively stimulate the Neiguan acupoint (PC6) with varying EDs, resulting in a biphasic dose–response effect on the autonomic nervous system (ANS) ( Chang et al, 2022 ).…”

A System Based on Photoplethysmography and Photobiomodulation for Autonomic Nervous System Measurement and Adjustment

“…On the other hand, the optical profile or radiation pattern of the light source is a parameter that affects the distribution of light in our tissue [ 51 ], thus affecting the efficiency of PBM. Dosage is another parameter that affects the effect of LA on adjusting the ANS [ 52 ]. The ANS may be adjusted by changing the dose on the same acupoint.…”

Increased Risk of Coronary Artery Disease in People with Diagnosis of Neuromuscular Disorders: A Nationwide Retrospective Population-Based Case–Control Study

“…Alternatively, considering the physiological perspective, within the recent publications from our team the investigations have revealed that the stimulation of the median nerve at various intensities has the capacity to modulate the parameters associated with heart rate variability (HRV) [39]. These parameters encompass the activity of the parasympathetic (PNS) and sympathetic nervous systems (SNS), and the association with CAD is also attributed to abnormal performance or heightened activity of the SNS [40].…”