Combinative Effect of Red and Far-Infrared Laser Therapy on Histological Changes of Injured Muscle in Rats

Ye Rim So; Ryon Hui Choe; Hyo Chol Pak; Chung Hyok Jong; Hyo Un Pak; Sun Gum Kim; Kwang Myong Jang

doi:10.5530/ijcep.2025.12.3.23

Ye Rim So Postgraduate School, Pyongyang College of Medical Sciences, Taedonggang District, Pyongyang, DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA.
Ryon Hui Choe Postgraduate School, Pyongyang College of Medical Sciences, Taedonggang District, Pyongyang, DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA.
Hyo Chol Pak Postgraduate School, Pyongyang College of Medical Sciences, Taedonggang District, Pyongyang, DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA.
Chung Hyok Jong Postgraduate School, Pyongyang University of Medical Sciences, Central District, Pyongyang, DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA.
Hyo Un Pak Postgraduate School, Pyongyang University of Medical Sciences, Central District, Pyongyang, DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA.
Sun Gum Kim Sinuiju College of Medical Sciences, Phyonghwa-dong, Sinuiju, North Phyongan Province, DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA.
Kwang Myong Jang Sinuiju College of Medical Sciences, Phyonghwa-dong, Sinuiju, North Phyongan Province, DEMOCRATIC PEOPLE’S REPUBLIC OF KOREA.

DOI: https://doi.org/10.5530/ijcep.2025.12.3.23

Keywords: Gastrocnemius Injury, Low-level laser therapy, Far-infrared laser therapy

Abstract

Background and Aim:The effects of red or far-infrared laser therapy are well known, but combinative effect of these laser on muscle injury has not yet been investigated in experimental studies. Here, we aim to examine the combinative effect of red and far-infrared laser therapy in a rat muscle injury model. Method: A total of male Wistar rats were randomly distributed into 3 groups: healthy control group (CG), untreated muscle injury group (MG) and combination of red and far-infrared laser therapy group (RFG). Gastrocnemius injury in rat was induced by a single blunt-impact trauma based on previous studies. Laser therapy was started within 24 h after muscle injury and applied every day for 21 days (1 min/day). Results: After combinative laser therapy (RFG), the area of damaged fibers, percentage in the area of collagen and leukocyte infiltration decreased significantly compared to MG. Conclusion: These results showed that the combination of Red and Far-infrared laser therapy was effective in muscle recovery and could modulate collagen and inflammatory process in injured muscle.