Institute of Biotechnology, University of Caxias do Sul, Caxias do Sul, RS, Brazil.
Lasers Med Sci. 2012 Jan;27(1):231-6. doi: 10.1007/s10103-011-0955-5. Epub 2011 Jul 8.
The aim of this work was to evaluate the effects of low-level laser therapy (LLLT) on exercise performance, oxidative stress, and muscle status in humans. A randomized double-blind placebo-controlled crossover trial was performed with 22 untrained male volunteers. LLLT (810 nm, 200 mW, 30 J in each site, 30 s of irradiation in each site) using a multi-diode cluster (with five spots - 6 J from each spot) at 12 sites of each lower limb (six in quadriceps, four in hamstrings, and two in gastrocnemius) was performed 5 min before a standardized progressive-intensity running protocol on a motor-drive treadmill until exhaustion. We analyzed exercise performance (VO(2 max), time to exhaustion, aerobic threshold and anaerobic threshold), levels of oxidative damage to lipids and proteins, the activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), and the markers of muscle damage creatine kinase (CK) and lactate dehydrogenase (LDH). Compared to placebo, active LLLT significantly increased exercise performance (VO(2 max) p = 0.01; time to exhaustion, p = 0.04) without changing the aerobic and anaerobic thresholds. LLLT also decreased post-exercise lipid (p = 0.0001) and protein (p = 0.0230) damages, as well as the activities of SOD (p = 0.0034), CK (p = 0.0001) and LDH (p = 0.0001) enzymes. LLLT application was not able to modulate CAT activity. The use of LLLT before progressive-intensity running exercise increases exercise performance, decreases exercise-induced oxidative stress and muscle damage, suggesting that the modulation of the redox system by LLLT could be related to the delay in skeletal muscle fatigue observed after the use of LLLT.
本研究旨在评估低水平激光疗法（LLLT）对人体运动表现、氧化应激和肌肉状态的影响。采用随机双盲安慰剂对照交叉试验，对 22 名未经训练的男性志愿者进行了研究。在每次下肢的 12 个部位（股四头肌 6 个部位，腘绳肌 4 个部位，腓肠肌 2 个部位）使用多二极管簇（每个部位 5 个点-每个部位 6J）进行 LLLT（810nm，200mW，每个部位 30J，每个部位 30s 照射），照射前 5 分钟在电动跑步机上进行标准化递增强度跑步方案，直至力竭。我们分析了运动表现（最大摄氧量、力竭时间、有氧阈和无氧阈）、脂质和蛋白质氧化损伤水平、抗氧化酶超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的活性以及肌肉损伤标志物肌酸激酶（CK）和乳酸脱氢酶（LDH）的水平。与安慰剂相比，活性 LLLT 显著增加了运动表现（最大摄氧量，p=0.01；力竭时间，p=0.04），而不改变有氧和无氧阈。LLLT 还降低了运动后的脂质（p=0.0001）和蛋白质（p=0.0230）损伤，以及 SOD（p=0.0034）、CK（p=0.0001）和 LDH（p=0.0001）酶的活性。LLLT 应用不能调节 CAT 活性。在递增强度跑步运动前使用 LLLT 可提高运动表现，降低运动引起的氧化应激和肌肉损伤，表明 LLLT 对氧化还原系统的调节可能与使用 LLLT 后观察到的骨骼肌疲劳延迟有关。
