Photobiomodulation Therapy for Exercise Recovery in Healthy Adults: A Systematic Review of Randomized Controlled Trials

Sammanfattning

Background: Exercise-induced muscle fatigue and muscle damage can impair performance following strenuous exercise. Photobiomodulation therapy (PBMT), also known as low-level laser therapy, has been proposed as a non-invasive intervention that may enhance muscle recovery through mechanisms related to mitochondrial stimulation and modulation of inflammatory processes. Aim: The aim of this systematic review was to evaluate the effects of PBMT on muscle recovery following exercise-induced fatigue or muscle damage in healthy adults. Methods: A systematic literature search was conducted in PubMed, Scopus, and Web of Science from database inception to 12 February 2026. Randomized controlled trials investigating PBMT as a recovery intervention following exercise in healthy adults were eligible for inclusion. Study selection, data extraction, and risk-of-bias assessment were conducted according to PRISMA guidelines. Muscle recovery outcomes included muscle strength, fatigue resistance, exercise performance, perceived muscle soreness, and biochemical markers of muscle damage. Results: A total of 794 records were screened by title and abstract, of which 142 articles were sought for full-text retrieval and 140 were assessed for eligibility. Twenty-three randomized controlled trials involving 636 participants met the inclusion criteria. Thirteen studies reported significant improvements in at least one recovery-related outcome following PBMT, whereas nine found no significant differences and one reported mixed findings, indicating inconsistent effects of PBMT on post-exercise recovery in healthy adults. Beneficial outcomes were more frequently reported in studies applying PBMT prior to exercise, although substantial variability was observed across studies in PBMT irradiation parameters, exercise protocols, participant characteristics, and recovery assessment timing. Conclusion: PBMT demonstrated inconsistent effects on post-exercise muscle recovery in healthy adults. Although some studies reported improvements in muscle strength recovery, fatigue resistance, muscle soreness, and biochemical markers of muscle damage, findings remained inconsistent across studies. Studies applying PBMT prior to exercise more frequently reported beneficial recovery-related effects, suggesting that treatment timing may represent an important influencing factor in PBMT effectiveness. However, no definitive optimal irradiation parameters or dose–response patterns could be identified. Interpretation of the evidence is limited by methodological heterogeneity across studies and relatively small sample sizes in several trials. Further well-designed randomized controlled trials using standardized protocols are needed to better clarify how treatment timing and irradiation parameters influence exercise recovery outcomes.