title: Light-emitting diode phototherapy improves muscle recovery after a damaging exercise.
abstract: The goal of the present study was to determine the effect of light-emitting diode phototherapy (LEDT) at 630 nm on muscle recovery after a damaging eccentric exercise bout. Seventeen healthy young male volunteers, without previous experience with eccentric exercise, were included in a randomized double-blinded placebo-controlled trial. They were divided into a LEDT (n = 8) and a PLACEBO group (n = 9). To induce muscle damage, subjects performed 30 eccentric contractions with a load of 100 % of maximal voluntary isometric contraction strength of the elbow flexors of the non-dominant arm. LEDT group subjects received biceps brachii phototherapy (λ 630 nm; total energy density, 20.4 J/cm2) immediately after the exercise bout. The LEDT in the placebo group was aimed at the muscle, but it remained turned off. Isometric muscle strength, muscle soreness, and elbow range of motion (ROM) were measured before and at 24, 48, 72, and 96 h the after eccentric exercise bout and compared between groups. Our results showed that the muscle soreness, muscle strength loss, and ROM impairments were significantly reduced up to 96 h after a damaging eccentric exercise bout for the LEDT group compared with the PLACEBO group. A single LEDT (630 nm) intervention immediately after a damaging eccentric exercise bout was effective in terms of attenuating the muscle soreness and muscle strength loss and ROM impairments.
authors.affiliation: Department of Biological Sciences, State University of Southwest Bahia (UESB), Jequie, 45210-506, Bahia, Brazil.
authors.forename: Lucio Santos
authors.initials: LS
authors.lastname: Borges
authors.forename: Mikhail Santos
authors.initials: MS
authors.lastname: Cerqueira
authors.forename: José Alberto
authors.initials: JA
authors.lastname: dos Santos Rocha
authors.forename: Luis Augusto Lupato
authors.initials: LA
authors.lastname: Conrado
authors.forename: Marco
authors.initials: M
authors.lastname: Machado
authors.forename: Rafael
authors.initials: R
authors.lastname: Pereira
authors.forename: Osmar
authors.initials: O
authors.lastname: Pinto Neto
mesh_terms: D000886:Anthropometry; D015444:Exercise / Q000502:physiology; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology* / Q000528:radiation effects*; D063806:Myalgia / Q000503:physiopathology; D010147:Pain Measurement; D010789:Phototherapy / Q000295:instrumentation* / Q000379:methods*; D010919:Placebos; D016059:Range of Motion, Articular; D020127:Recovery of Function; D055815:Young Adult
chemical_list: D010919:Placebos