title: Effects of low-level laser therapy on performance, inflammatory markers, and muscle damage in young water polo athletes: a double-blind, randomized, placebo-controlled study.
abstract: This study aimed to evaluate the effects of 5 days of 810-nm low-level laser therapy (LLLT) intervention on inflammatory and muscle damage markers and performance in young water polo players. Twenty young male water polo players participated in the study, which was designed as a randomized, double-blinded, placebo-controlled trial. Active LLLT or an identical placebo LLLT were delivered to eight points on the adductor muscle region immediately after each training day. Performance was measured by a 200-m maximal swimming (P200) and a 30-s crossbar jump test (30CJ) which was performed every day before training, and blood samples were drawn pre and post the final LLLT intervention to measure interleukins (IL) and muscle damage markers. There was no significant change in the P200 exercise in the LLLT group compared with the placebo group but there was a moderate improvement in the 30CJ (8.7 ± 2.6 %). IL-1β and tumor necrosis factor-alpha presented increased (P < 0.016) concentration within group 48 h after the last LLLT intervention compared to pre, 0, and 24 h, but did not differ between groups. IL-10 increased over time in the placebo group and reached a moderate effect compared to the LLLT group. The creatine kinase decreased significantly (P = 0.049) over the time within the LLLT treatment group, but there was no significant change in lactate dehydrogenase (P = 0.150). In conclusion, LLLT resulted in a non-significant, but small to moderate effect on inflammatory and muscle damage markers and a moderate effect on performance in water polo players. In addition, the lack of positive results could be due to the small area covered by irradiation and this should be considered in future studies.
authors.affiliation: Faculty of Sciences, Department of Physical Education, UNESP - Univ Estadual Paulista, Av. Eng. Luiz Edmundo Carrijo Coube, 14-01, Vargem Limpa, CEP 17033-360, Bauru, São Paulo, Brazil. azagatto@yahoo.com.br.
authors.forename: Alessandro Moura
authors.initials: AM
authors.lastname: Zagatto
authors.affiliation: State University of Londrina, Londrina, Paraná, Brazil.
authors.forename: Solange
authors.initials: S
authors.lastname: de Paula Ramos
authors.affiliation: State University of Londrina, Londrina, Paraná, Brazil.
authors.forename: Fábio Yuzo
authors.initials: FY
authors.lastname: Nakamura
authors.affiliation: Department of Physical Education, Faculty of Science and Technology, UNESP - Univ Estadual Paulista, Presidente Prudente, São Paulo, Brazil.
authors.forename: Fábio Santos
authors.initials: FS
authors.lastname: de Lira
authors.affiliation: Laboratory of Photobiomodulation and Modeling of Biological Phenomena, Universidade de Mogi das Cruzes (UMC), Mogi das Cruzes, São Paulo, Brazil.
authors.forename: Rodrigo Álvaro Brandão
authors.initials: RÁ
authors.lastname: Lopes-Martins
authors.affiliation: Research Laboratory in Physiotherapy, Sacred Heart University, Bauru, São Paulo, Brazil.
authors.forename: Rodrigo Leal
authors.initials: RL
authors.lastname: de Paiva Carvalho
mesh_terms: D000293:Adolescent; D056352:Athletes; D015415:Biomarkers / Q000097:blood; D003402:Creatine Kinase / Q000097:blood; D004311:Double-Blind Method; D006801:Humans; D016753:Interleukin-10 / Q000097:blood; D053583:Interleukin-1beta / Q000097:blood; D007770:L-Lactate Dehydrogenase / Q000097:blood; D028022:Low-Level Light Therapy; D008297:Male; D009048:Motor Skills; D018482:Muscle, Skeletal / Q000473:pathology / Q000528:radiation effects*; D013550:Swimming; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D015415:Biomarkers; C508585:IL1B protein, human; D053583:Interleukin-1beta; C439524:TNF protein, human; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase
keywords: Cytokines; Laser; Muscle injuries; Water polo