Effects of pre-irradiation of low-level laser therapy with different doses and wavelengths in skeletal muscle performance, fatigue, and skeletal muscle damage induced by tetanic contractions in rats

Author(s):Show less -

Santos, Larissa Aline ^[1] ; Marcos, Rodrigo Labat ^[2] ; Tomazoni, Shaiane Silva ^[3] ; Vanin, Adriane Aver ^[1] ; Antonialli, Fernanda Colella ^[1] ; Grandinetti, Vanessa dos Santos ^[2] ; Albuquerque-Pontes, Gianna Moes ^[2] ; Vicente de Paiva, Paulo Roberto ^[2] ; Brandao Lopes-Martins, Rodrigo Alvaro ^[3] ; Camillo de Carvalho, Paulo de Tarso ^{[1, 2]} ; Bjordal, Jan Magnus ^{[4, 5]} ; Pinto Leal-Junior, Ernesto Cesar ^{[1, 2]}

Affiliation

^[1] Univ Nove Julho UNINOVE, Postgrad Program Rehabil Sci, BR-01504001 Sao Paulo - Brazil

^[2] Univ Nove Julho UNINOVE, Postgrad Program Biophoton Appl Hlth Sci, BR-01504001 Sao Paulo - Brazil

^[3] Univ Sao Paulo, Dept Pharmacol, BR-05508900 Sao Paulo - Brazil

^[4] Univ Bergen, Fac Med & Dent, Dept Global Publ Hlth, Physiotherapy Res Grp, N-5020 Bergen - Norway

^[5] Bergen Univ Coll, Ctr Knowledge Based Practice, N-5009 Bergen - Norway

• Document type: Journal article
• Source: Lasers in Medical Science; v. 29, n. 5, p. 1617-1626, SEP 2014.
• Web of Science Citations: 35

Abstract

This study aimed to evaluate the effects of low-level laser therapy (LLLT) immediately before tetanic contractions in skeletal muscle fatigue development and possible tissue damage. Male Wistar rats were divided into two control groups and nine active LLLT groups receiving one of three different laser doses (1, 3, and 10 J) with three different wavelengths (660, 830, and 905 nm) before six tetanic contractions induced by electrical stimulation. Skeletal muscle fatigue development was defined by the percentage (%) of the initial force of each contraction and time until 50 % decay of initial force, while total work was calculated for all six contractions combined. Blood and muscle samples were taken immediately after the sixth contraction. Several LLLT doses showed some positive effects on peak force and time to decay for one or more contractions, but in terms of total work, only 3 J/660 nm and 1 J/905 nm wavelengths prevented significantly (p < 0.05) the development of skeletal muscle fatigue. All doses with wavelengths of 905 nm but only the dose of 1 J with 660 nm wavelength decreased creatine kinase (CK) activity (p < 0.05). Qualitative assessment of morphology revealed lesser tissue damage in most LLLT-treated groups, with doses of 1-3 J/660 nm and 1, 3, and 10 J/905 nm providing the best results. Optimal doses of LLLT significantly delayed the development skeletal muscle performance and protected skeletal muscle tissue against damage. Our findings also demonstrate that optimal doses are partly wavelength specific and, consequently, must be differentiated to obtain optimal effects on development of skeletal muscle fatigue and tissue preservation. Our findings also lead us to think that the combined use of wavelengths at the same time can represent a therapeutic advantage in clinical settings. (AU)

• FAPESP's process: 12/06832-5 - Low-level laser therapy and topical sodium diclofenac in contusion-induced skeletal muscle injury in rats
• Grantee: Lúcio Frigo
• Support Opportunities: Regular Research Grants
• FAPESP's process: 10/52404-0 - Low-level laser therapy in skeletal muscle fatigue and post-exercise recovery: Optimal parameters and effects in long-duration exercise
• Grantee: Ernesto Cesar Pinto Leal Junior
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 12/04295-2 - Analysis of dose-response patterns of low-level laser therapy with different wavelengths in skeletal muscle fatigue in rats
• Grantee: Larissa Aline Santos
• Support Opportunities: Scholarships in Brazil - Master