title: The effect of low-level laser therapy (LLLT) applied prior to muscle injury.
abstract: OBJECTIVE
  To evaluate the effect of LLLT (780 nm; 10 J/cm2, 40 mW, 3.2 J) prior to injury on the morphological analysis, collagen deposition, and activity of matrix metalloproteinase-2 (MMP-2).
  
  
  METHODS
  Wistar rats were divided into groups: control; sham; only LLLT; only muscle injury and LLLT + injury. The rats were euthanized at 1, 3, and 7 days following cryoinjury to muscle that was removed for analysis.
  
  
  RESULTS
  LLLT applied prior to muscle injury led to a reduction in myonecrosis and inflammatory cells, an increase of blood vessels and immature muscle fibers. An increase in MMP-2 activity and a decrease in collagen deposition were also found, with a better collagen organization and distribution.
  
  
  CONCLUSIONS
  LLLT applied immediately prior to injury had positive effects during the muscle regeneration process. Therefore, this resource may have considerable therapeutic value, especially for athletes who practice sports in which there is a constant risk of muscle injury. Lasers Surg. Med. 47:571-578, 2015. © 2015 Wiley Periodicals, Inc.
authors.affiliation: Rehabilitation Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Beatriz Guimarães
authors.initials: BG
authors.lastname: Ribeiro
authors.affiliation: Rehabilitation Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Agnelo Neves
authors.initials: AN
authors.lastname: Alves
authors.affiliation: Biophotonics Applied to Health Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Lucas Andreo Dias Dos
authors.initials: LADD
authors.lastname: Santos
authors.affiliation: Rehabilitation Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.|Biophotonics Applied to Health Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Kristianne Porta Santos
authors.initials: KPS
authors.lastname: Fernandes
authors.affiliation: Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Tatiane Matarazzo
authors.initials: TM
authors.lastname: Cantero
authors.affiliation: Biophotonics Applied to Health Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Mariana Teixeira
authors.initials: MT
authors.lastname: Gomes
authors.affiliation: Biophotonics Applied to Health Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Cristiane Miranda
authors.initials: CM
authors.lastname: França
authors.affiliation: Biophotonics Applied to Health Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Daniela
authors.initials: D
authors.lastname: de Fátima Teixeira da Silva
authors.affiliation: Rehabilitation Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.|Biophotonics Applied to Health Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Sandra Kalil
authors.initials: SK
authors.lastname: Bussadori
authors.affiliation: Rehabilitation Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.|Biophotonics Applied to Health Sciences, Universidade Nove de Julho - UNINOVE, São Paulo - SP, Brazil.
authors.forename: Raquel Agnelli
authors.initials: RA
authors.lastname: Mesquita-Ferrari
keywords: low-level laser therapy; matrix metalloproteinase 2; muscle; regeneration collagen; skeletal