An optimal recovery between training sessions is of similar if not greater importance as the training content and program of the training, itself. One of the most used strategies for improving recovery is the ingestion of supplements. The present study aimed to evaluate the effect of 5 mg oral melatonin supplementation on the recovery from repeated sprint (RSA) of performance and biochemical responses (i.e. oxidative stress, leukocytosis cellular damage) after an intensive training camp (TC). Twenty soccer players performed an RSA test before and after an intensive six-day TC associated with nocturnal melatonin (n = 10) or placebo (n = 10) ingestion. Resting and post-RSA test blood samples were obtained before and after the TC. Compared to placebo, melatonin intake decreased resting oxidative stress markers (i.e, advanced oxidation protein products), leukocytosis (i.e. white blood cells (WBC), neutrophils (NE)) and biomarkers of cellular damage (i.e. creatine kinase (CK)). It also lowered post-exercise leukocytosis (i.e. WBC, NE, lymphocytes (LY), monocytes (MO)) and biomarkers of cellular damage (i.e. CK, aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT)) and raised the activity of the main antioxidant enzymes (i.e. glutathione peroxidase (GPx), glutathione reductase (GR)). In addition, compared to placebo, melatonin reduced the deterioration of the best and total time during the RSA test after the TC. In conclusion, nocturnal melatonin supplementation during an intensive TC alleviated oxidative stress, leukocytosis and cellular damage and improved recovery of RSA performance in soccer players.

培训课程之间的最佳恢复与培训本身的培训内容和计划相比，具有甚至更高的重要性。摄取补品是改善康复的最常用策略之一。本研究旨在评估5 mg口服褪黑激素对强化训练营（TC）后从反复冲刺（RSA）的表现和生化反应（即氧化应激，白细胞增多症细胞损害）恢复的影响。20名足球运动员在与夜间褪黑素（n = 10）或安慰剂（n = 10）摄入有关的强化六天TC前后进行了RSA测试。在TC之前和之后获取静息和RSA测试后的血液样本。与安慰剂相比，褪黑激素的摄入降低了静息氧化应激指标（即高级氧化蛋白产物），白细胞增多症（即白细胞（WBC），中性粒细胞（NE））和细胞损伤的生物标志物（即肌酸激酶（CK））。它也降低了运动后白细胞增多（即，WBC，NE，淋巴细胞（LY），单核细胞（MO））和细胞损伤（生物标志物即。CK，谷草转氨酶（ASAT），谷丙转氨酶（ALAT）），提高了活性主要抗氧化酶（即。谷胱甘肽过氧化物酶（GPx），谷胱甘肽还原酶（GR））。此外，与安慰剂相比，褪黑素减少了TC后RSA测试期间最佳和总时间的恶化。总之，在强化TC期间夜间补充褪黑素可减轻足球运动员的氧化应激，白细胞增多和细胞损伤，并改善RSA表现。