Effects of Laser Acupuncture on Delayed Onset Muscle Soreness of the Biceps Brachii Muscle: A Randomized Controlled Trial

Abstract

Objectives. The aim of this study was to explore the effects of laser acupuncture on improvement of recovery and muscle performance in delayed muscle soreness (DOMS) when applied before exercise. Methods. This randomized, blinded, and controlled study included healthy participants (n = 40) who were randomized into laser acupuncture and placebo groups. Laser acupuncture was applied to the Tianquan (PC2) and Chihtseh acupoints (LU5) at a dose of 36 J and energy density of 9.7 J/cm2 before inducing DOMS. The placebo group received sham laser acupuncture with no laser output. Visual analog scale (VAS), proprioception, pressure pain threshold (PPT), arm circumference, and muscle strength were observed at the baseline and 24, 48, 72, and 96 h after induction of DOMS. Results. Significant changes in the VAS (F4,  43.96 = 31.47; p = 0.001), PPT (F4,  1.35 = 35.07; p = 0.001), normalized arm circumference (F4,  0.001 = 3.87; p = 0.005), and normalized muscle strength (F4,  0.31 = 24.99; p = 0.001) were observed within the groups over time (p < 0.05), but there were no significant differences between the two groups (p > 0.05). Normalized arm circumference was significantly different between the two groups at 48 and 72 h after induction of DOMS (p < 0.05). Conclusion. Photobiomodulation therapy on Tianquan (PC2) and Chihtseh acupoints (LU5) before the exercise did not significantly decrease DOMS and increase muscle performance. Laser acupuncture as a supplemental therapy seemed to have no effect on DOMS prevention.