Effect of Pulsed Electromagnetic Stimulation on Delayed Onset Muscle Soreness: Randomized Sham-Controlled Trial

Background: The effect of pulsed electromagnetic field (PEMF) therapy on muscle performance and serum creatine kinase (CK) and myoglobin (Mb) values - the biomarkers of muscle damage in experimentally induced delayed onset muscle soreness (DOMS) - has yet to be investigated. PEMF therapy is known to be effective to reduce muscle pain, muscle recovery time, fatigue but not to increase muscle force production. The study aimed to compare the effect of PEMF and sham therapy on experimentally induced DOMS in sedentary undergraduate college students. Hypothesis: PEMF therapy would improve pain, pressure pain threshold (PPT), functional performance, serum CK activity, and Mb concentration compared with the sham intervention. Study Design: Randomized, participant- and assessor-blinded, sham-controlled study. Level of Evidence: Level 2. Methods: This study was conducted at Pamukkale University Sarayköy Vocational School. A total of 52 healthy sedentary people received 3 consecutive days of active (Experimental group, n = 26) or sham (Sham group, n = 26) PEMF therapy 24 hours after DOMS induction with a drop-jump protocol. Pain intensity, PPT, functional performance, serum CK activity, and Mb concentration were assessed at baseline, 24 hours and 72 hours after DOMS induction protocol. Results: The drop-jump protocol induced DOMS successfully in both groups ( P < 0.05). All outcome measures were improved in the experimental group ( P < 0.05). Mean change scores of PPT ( P = 0.53), functional performance ( P = 0.10), serum CK ( P = 0.38), and Mb concentrations ( P = 0.08) were not significantly different between baseline and 72 hours in the sham group. Statistically significant decreases in Mb concentrations were determined in the sham group ( P = 0.001). Conclusion: Compared with sham, PEMF therapy improved pain, PPT, functional performance, serum CK activity, and Mb concentration. The duration of PEMF therapy was sufficient to resolve the PPT, functional performance, and serum CK and Mb concentrations associated with DOMS. Clinical Relevance: This study adds to existing knowledge in showing that, compared with sham, PEMF therapy improved pain, PPT, functional performance, serum CK activity, and Mb concentration.