The Influence of Acupuncture Stimulation on Dynamic Electromyographic Activity
Tim Hideaki Tanaka, Ph.D. Kazushi Nishijo, Ph.D.
(Published in Journal of The Japanese Society of Acupuncture, Vol. 48, No. 2, 105-119, 1998)
The study investigated the influence of acupuncture on synergistic coordination by observing dynamic lumbar electromyographic activity. Thirty healthy subject’s left and right lumbar paraspinal (LP) EMG activity was recorded during a 45 degrees trunk flexion-return movement, and the maximum RMS EMG activity (MREA) during this movement in each side was compared. Twenty subjects showed less than 20% LP MREA difference (symmetrical subjects-SS) between the left and right side and 10 subjects showed more than a 20 % difference (asymmetrical subjects-AS). SS were reevaluated after lying on a treatment table in prone position for 2 minutes and little change was observed in the degree of LP MREA asymmetry (P=0.164). AS were administered acupuncture stimulation on LP muscles. After the stimulation, a significant reduction in LP MREA asymmetry was observed (P=0.049), with a clear increase in symmetry of dynamic EMG activity for 9 out of 10 subjects. No specific pattern of response in LP MREA values was observed in the stimulated side following the stimulation. On the non-stimulated side, there was a significant trend of a LP MREA decrease when the baseline value for that side was high (P=0.037), and an increase when it was low (0.0185). The study did not attempt to explore the exact mechanism of LP MIEA asymmetry reduction following acupuncture, however, it suggested that the response occurred as a result of interaction between the central and peripheral nerves causing simultaneously a systemic and local response. This study indicated that acupuncture stimulation significantly decreased the asymmetrical dynamic EMG activity, which suggests that acupuncture treatment may be a useful method for decreasing functional muscular distortion and improving synergistic coordination.