Local increase in trapezius muscle oxygenation during and after acupuncture
1 Tokyo Therapeutic Institute, 3 Sanei-cho, Shinjuku-ku, Tokyo 160-0008, Japan
2 National Institute of Fitness and Sports in Kanoya, 1 Shiromizu, Kanoya, Kagoshima 891-2393, Japan
3 Department of Sports Medicine for Health Promotion Tokyo Medical University, 6-1-1, Shinjuku, Shinjuku-ku Tokyo 160-8402, Japan
4 Department of Electrical and Electronic Engineering Faculty of Engineering Shizuoka University, 3-5-1 Johoku, Hamamatsu, Shizuoka 432-8561, Japan
5 Department of Neurology, University of Cincinnati, 3125 Eden Ave, 2327 Vontz Center for Molecular Studies, PO Box 670536, Cincinnati, OH 45267-0536, USA
Dynamic Medicine 2009, 8:2 doi:10.1186/1476-5918-8-2Published: 16 March 2009
This study aimed to compare the trapezius muscle blood volume and oxygenation in the stimulation region and in a distant region in the same muscle during acupuncture stimulation (AS). We hypothesized that AS provokes a localized increase in muscle blood volume and oxygenation in the stimulation region.
Two sets of near-infrared spectrometer (NIRS) probes, with 40-mm light-source detector spacing, were placed on the right trapezius muscle, with a 50-mm distance between the probes. Changes in muscle oxygenation (oxy-Hb) and blood volume (t-Hb) in stimulation and distant regions (50 mm away from the stimulation point) were measured using NIRS. Nine healthy acupuncture-experienced subjects were chosen as the experimental (AS) group, and 10 healthy acupuncture-experienced subjects were chosen for the control (no AS) group. Measurements began with a 3-min rest period, followed by "Jakutaku" (AS) for 2 min, and recovery after stimulation.
There was a significant increase in oxy-Hb (60.7 μM at maximum) and t-Hb (48.1 μM at maximum) in the stimulation region compared to the distant region. In the stimulation region, a significant increase in oxy-Hb and t-Hb compared with the pre-stimulation level was first noted at 58.5 s and 13.5 s, respectively, after the onset of stimulation.
In conclusion, oxygenation and blood volume increased, indicating elevated blood flow to the small vessels, not in the distant region used in this study, but in the stimulation region of the trapezius muscle during and after a 2-min AS.