Photobiomodulation Therapy at 808 nm Does Not Improve Biceps Brachii Performance to Exhaustion and Delayed-Onset Muscle Soreness in Young Adult Women: A Randomized, Controlled, Crossover Trial

ObjectiveThis study aims to investigate the effects of laser photobiomodulation (PBM) at 808 nm on biceps brachii performance to exhaustion, rating of perceived exertion (RPE), and delayed onset muscle soreness (DOMS) in untrained young women.MethodsThirteen young women (20.1 ± 2.9 years) participated in a crossover study in which they received, in a counterbalanced manner, active and placebo laser PBM on two occasions (T1 and T2), separated by a 7-day washout period. During T1 and T2, participants received active (100 mW output power, irradiance of 35.7 W cm–2, and total energy of 28 J/arm) or placebo laser irradiation on the biceps brachii muscle at 20 min before the repetitions-to-failure test [six sets at 60% of one-repetition maximum (1RM) until failure] for elbow flexion exercise. The number of repetitions performed and RPE over the six sets, as well as DOMS from basal up to 72 h after the repetitions-to-failure test, were recorded.ResultsThere was a significant (time, p < 0.05) reduction in the number of repetitions performed and an increase in RPE over six sets, with no statistical differences between placebo and active laser conditions (treatment × time, p > 0.05). DOMS increased at 24 h postexercise and progressively returned to baseline after 72 h in both conditions (time, p < 0.05; treatment × time, p > 0.05).ConclusionOur results indicate that acute laser PBM at 808 nm does not improve biceps brachii performance to exhaustion, RPE, and DOMS in untrained women.

Influência da laserterapia associada ao alongamento passivo sobre o músculo isquiotibial

Introdução: A laserterapia tem sido reportada por seus efeitos sobre o sistema neuromuscular. Objetivo: O objetivo neste estudo foi avaliar a influência da laserterapia associada ao alongamento passivo de músculo isquiotibial em indivíduos saudáveis. Método: Trinta e uma voluntárias foram divididas nos quatro seguintes grupos: controle (C), alongamento (AL), alongamento e placebo laser (LP+AL) e alongamento e laser (L+AL). Os grupos, exceto o controle, realizaram nove sessões de alongamento passivo. O grupo L+AL recebeu irradiação no trajeto do músculo isquiotibial, previamente às sessões de alongamento (GaAlAs, 830 nm, 30 mW, 6 J/cm2, 26 segundos). Foram avaliadas a flexibilidade (goniometria) e a atividade muscular (eletromiografia de superfície). Resultados: O alongamento passivo, associada à laserterapia, promoveu aumento significativo da flexibilidade (p>0,014) e da atividade muscular (p

Effectiveness of transmeatal low power laser irradiation for chronic tinnitus

Objective:To evaluate effectiveness of 5 mW laser irradiation in the treatment of chronic tinnitus.Study design:Prospective, randomised, double-blind study.Methods:This investigation included 66 ears in 45 patients with chronic unilateral or bilateral tinnitus. A 5 mW laser with a wavelength of 650 nm, or placebo laser, was applied transmeatally for 15 minutes, once daily for a week. A questionnaire was administered which asked patients to score their symptoms on a five-point scale, before and two weeks after laser irradiation. A decrease of one scale point, regarding the loudness, duration and degree of annoyance of tinnitus, was accepted to represent an improvement.Results:The loudness, duration and degree of annoyance of tinnitus were improved, respectively, in up to 48.8, 57.7 and 55.5 per cent of the patients in the active laser group. No significant improvement was observed in the placebo laser group.Conclusion:Transmeatal, low power (5 mW) laser irradiation was found to be useful for the treatment of chronic tinnitus.

The efficacy of strain counterstrain mobilization in patients with painful hallux abducto valgus bunions

The purpose of this prospective, randomised, placebo controlled study was to determine the efficacy of strain counterstrain mobilization in patients suffering with painful Hallux Abducto Valgus Bunions (HAVB). The mobilization group received strain counterstrain mobilization while the placebo group received placebo laser. The study involved sixty patients; thirty in each group, which were selected from the general population. Each patient was treated five times within a three week period.

Effect of Gallium Aluminum Arsenide Triple-Diode Laser on Median Nerve Latency in Human Subjects

The purpose of this study was to determine the effect of a continuous-wave gallium aluminum arsenide (GaAlAs) triple-diode laser (830 nm, 90 mW) on median nerve motor and sensory evoked potential latencies. This investigation attempted to determine whether the location of treatment, in an area where the median nerve was either superficial or deep, influenced the effectiveness of the laser treatment. Forty-two healthy adult volunteers were randomly assigned to receive 12 J of GaAlAs laser treatment or placebo laser treatment at a single point on the wrist or forearm. The results of this study indicated no difference between the pre- or posttreatment latency measurements in either the placebo laser or the GaAlAs laser group. Motor and sensory latencies varied significantly by location of treatment, but there was no significant interaction between laser treatment group and location. GaAlAs triple-diode laser treatment did not significantly affect median nerve motor or sensory latency.