What is the ideal dose and power output of low-level laser therapy (810 nm) on muscle performance and post-exercise recovery? Study protocol for a double-blind, randomized, placebo-controlled trial

Author(s):Show less -

de Oliveira, Adriano Rodrigues ^[1] ; Vanin, Adriane Aver ^[2] ; De Marchi, Thiago ^[3] ; Antonialli, Fernanda Colella ^[2] ; Grandinetti, Vanessa dos Santos ^[1] ; Vicente de Paiva, Paulo Roberto ^[1] ; Albuquerque Pontes, Gianna Moes ^[1] ; Santos, Larissa Aline ^[2] ; Aleixo Junior, Ivo de Oliveira ^[2] ; Camillo de Carvalho, Paulo de Tarso ^{[2, 1]} ; Bjordal, Jan Magnus ^[4] ; Pinto Leal-Junior, Ernesto Cesar ^{[2, 1]}

Affiliation

^[1] Univ Nove de Julho UNINOVE, Postgrad Program Biophoton Appl Hlth Sci, BR-01504001 Sao Paulo - Brazil

^[2] Univ Nove de Julho UNINOVE, Postgrad Program Rehabil Sci, BR-01504001 Sao Paulo - Brazil

^[3] Univ Caxias do Sul, Sports Med Inst, BR-95070560 Caxias Do Sul, RS - Brazil

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

• Document type: Journal article
• Source: Trials; v. 15, FEB 27 2014.
• Web of Science Citations: 4

Abstract

Background: Recent studies involving phototherapy applied prior to exercise have demonstrated positive results regarding the attenuation of muscle fatigue and the expression of biochemical markers associated with recovery. However, a number of factors remain unknown, such as the ideal dose and application parameters, mechanisms of action and long-term effects on muscle recovery. The aims of the proposed project are to evaluate the long-term effects of low-level laser therapy on post-exercise musculoskeletal recovery and identify the best dose and application power/irradiation time. Design and methods: A double-blind, randomized, placebo-controlled clinical trial with be conducted. After fulfilling the eligibility criteria, 28 high-performance athletes will be allocated to four groups of seven volunteers each. In phase 1, the laser power will be 200 mW and different doses will be tested: Group A (2 J), Group B (6 J), Group C (10 J) and Group D (0 J). In phase 2, the best dose obtained in phase 1 will be used with the same distribution of the volunteers, but with different powers: Group A (100 mW), Group B (200 mW), Group C (400 mW) and Group D (0 mW). The isokinetic test will be performed based on maximum voluntary contraction prior to the application of the laser and after the eccentric contraction protocol, which will also be performed using the isokinetic dynamometer. The following variables related to physical performance will be analyzed: peak torque/maximum voluntary contraction, delayed onset muscle soreness (algometer), biochemical markers of muscle damage, inflammation and oxidative stress. Discussion: Our intention, is to determine optimal laser therapy application parameters capable of slowing down the physiological muscle fatigue process, reducing injuries or micro-injuries in skeletal muscle stemming from physical exertion and accelerating post-exercise muscle recovery. We believe that, unlike drug therapy, LLLT has a biphasic dose-response pattern. (AU)

• 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