Efficacy of Acute and Long-Term Photobiomodulation Therapy on Fatigue and Muscle Performance in Different Animal Models: a Systematic Review

Abstract

Abstract Muscular fatigue is associated with repeated muscle contraction exercises and with intense use of muscles with high intensity leading to a decline of performance and inability to continue with the same activity original intensity of activity. One of most promising interventions is the photobiomodulation therapy (PBMT). The objective was to analyze the results of the studies that investigated the effects of acute and long-term photobiomodulation in experimental animal models of muscle fatigue levels. The review was registered with PROSPERO (CRD42021274444). 10 studies were identified (n=366 animals). 77% used histological analysis and blood level of lactate measures to record changes in fatigue and were considered moderate evidence. Nine chose isotonic contractions and one study opted for isometric contraction to induce fatigue. 77% applied long term PBMT and 33% applied an acute form. Most of the studies used the infrared wavelength; the power output varied from 0.625mW to 300mW and energy per point varied from 0.105J to 12J. This review demonstrates that PBMT has positive effects in acute and long-term treatment decreasing the level of fatigue and accelerating exercise performance in different animal models, even with distinct PBMT parameters and number of therapy sessions

Keywords

• muscle fatigue
• systematic review
• performance
• low-level laser therapy
• animal models