Background
There is a gap in understanding the effects of different acupoints and treatment methods (acupuncture and moxibustion) on microcirculatory changes in the lumbar region.
Objective
This study aimed to assess the thermal effects of acupuncture at Weizhong (BL40), with acupuncture at Chize (LU5) and moxibustion at both acupoints as control interventions.
Design, setting, participants and interventions
In this randomized controlled trial, 140 healthy participants were equally divided into four groups: acupuncture at BL40 (Acu-BL40), acupuncture at LU5 (Acu-LU5), moxibustion at BL40 (Mox-BL40) and moxibustion at LU5 (Mox-LU5). Participants underwent a 30-minute session of their assigned treatment. Infrared thermal imaging was used to collect temperature data on the areas of interest for analysis.
Main outcome measures
The primary measure was the change in average temperature of the observed area after the intervention. The secondary measures included periodic temperature changes every 5 min and the temperature changes of the Governor Vessel and Bladder Meridian in the observed area after the intervention.
Results
Significant interactions were observed between treatments and acupoints affecting temperature (P < 0.001). The Acu-BL40 group showed a notably higher increase in mean temperature after 30 min compared to the Acu-LU5 and Mox-BL40 groups, with increases of 0.29 (95% confidence interval [CI] = 0.17 to 0.41) and 0.24 (95% CI = 0.08 to 0.41) °C, respectively.
Conclusion
Acupuncture at BL40 acupoint can significantly increase the mean temperature in the observed area, highlighting the specific thermal effect of acupuncture compared to moxibustion in the lumbar area. This suggests a potential therapeutic benefit of acupuncture at BL40 for managing lumbar conditions.
Trial registration: ClinicalTrials.gov (NCT05665426).

Key words: Acupuncture, Moxibustion, BL40, Factorial design, Lumbar warming effect, Infrared thermography