Leal Junior Ernesto Cesar Pinto, Lopes-Martins Rodrigo Alvaro Brandão, Vanin Adriane Aver, Baroni Bruno Manfredini, Grosselli Douglas, De Marchi Thiago, Iversen Vegard V, Bjordal Jan Magnus
Laboratory of Human Movement (LMH), University of Caxias do Sul, Rua Francisco Getúlio Vargas, 1130, Caxias do Sul, 95070-560, Rio Grande do Sul, Brazil.
Lasers Med Sci. 2009 May;24(3):425-31. doi: 10.1007/s10103-008-0592-9. Epub 2008 Jul 23.
This study aimed to investigate the effect of 830 nm low-level laser therapy (LLLT) on skeletal muscle fatigue. Ten healthy male professional volleyball players entered a crossover randomized double-blinded placebo-controlled trial. Active LLLT (830 nm wavelength, 100 mW output, spot size 0.0028 cm(2), 200 s total irradiation time) or an identical placebo LLLT was delivered to four points on the biceps humeri muscle immediately before exercises. All subjects performed voluntary biceps humeri contractions with a load of 75% of the maximum voluntary contraction (MVC) force until exhaustion. After active LLLT the mean number of repetitions was significantly higher than after placebo irradiation [mean difference 4.5, standard deviation (SD) +/- 6.0, P = 0.042], the blood lactate levels increased after exercises, but there was no significant difference between the treatments. We concluded that 830 nm LLLT can delay the onset of skeletal muscle fatigue in high-intensity exercises, in spite of increased blood lactate levels.
本研究旨在探讨830纳米低强度激光疗法（LLLT）对骨骼肌疲劳的影响。十名健康的男性职业排球运动员参与了一项交叉随机双盲安慰剂对照试验。在运动前，将活性LLLT（波长830纳米，输出功率100毫瓦，光斑大小0.0028平方厘米，总照射时间200秒）或相同的安慰剂LLLT照射到肱二头肌的四个点上。所有受试者以最大自主收缩（MVC）力量的75%进行肱二头肌的自主收缩，直至力竭。活性LLLT治疗后，平均重复次数显著高于安慰剂照射后[平均差异4.5，标准差（SD）±6.0，P = 0.042]，运动后血乳酸水平升高，但两种治疗之间无显著差异。我们得出结论，尽管血乳酸水平升高，但830纳米LLLT可延缓高强度运动中骨骼肌疲劳的发生。
