Changes in oxy-Hb, deoxy-Hb, and t-Hb at pre-stimulation rest and during acupuncture stimulation (AS) and recovery from AS in the stimulation and distant regions in the trapezius muscle. A significant difference in oxy-Hb and t-Hb is noted between stimulation and distant regions as indicated by (#). Significant increases in oxy-Hb and t-Hb compared with pre-stimulation levels are indicated by (*). The number of the subjects is 9. Values are represented as means ± S.D.