Abstract:
Exercise overproduces oxygen reactive species (ROS) and eventually exceeds the body\'s antioxidant capacity to neutralize them. The ROS produce damaging effects on the cell membrane and contribute to skeletal muscle damage. Selenium (Se), a natural mineral trace element, is an essential component of selenoproteins that plays an important role in antioxidant defense. The activity of the enzyme glutathione peroxidase (GPx), a highly-efficient antioxidant enzyme, is closely dependent on the presence of Se. These properties of Se may be potentially applicable to improve athletic performance and training recovery. We systematically searched for published studies to evaluate the effectiveness of Se supplementation on antioxidant defense system, muscle performance, hormone response, and athletic performance among physically active individuals. We used the Preferred Reporting Elements for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and searched in SCOPUS, Web of Science (WOS), and PubMed databases to identify published studies until March 2020. The systematic review incorporated original studies with randomized controlled crossover or parallel design in which intake of Se administered once a day was compared with the same placebo conditions. No exclusions were applied for the type of physical exercise performed, the sex, nor the age of the participants. Among 150 articles identified in the search, 6 met the criteria and were included in the systematic review. The methodological quality of the studies was evaluated using the McMaster Critical Review Form. Oral Se supplementation with 180 µg/day or 240 µg/day (selenomethionine) and 200 µg/day (Sodium Selenite), significantly decreased lipid hydroperoxide levels and increased GPx in plasma, erythrocyte, and muscle. No significant effects were observed on athletic performance, testosterone hormone levels, creatine kinase activity, and exercise training-induced adaptations on oxidative enzyme activities or on muscle fiber type myosin heavy chain expression. In addition, Se supplementation showed to have a dampening effect on the mitochondria changes in chronic and acute exercise. In summary, the use of Se supplementation has no benefits on aerobic or anaerobic athletic performance but it may prevent Se deficiencies among athletes with high-intensity and high-volume training. Optimal Se plasma levels may be important to minimize chronic exercise-induced oxidative effects and modulate the exercise effect on mitochondrial changes.
摘要:
运动会过度产生氧反应物质(ROS),并最终超过身体的抗氧化能力来中和它们。ROS对细胞膜产生破坏作用并有助于骨骼肌损伤。硒(Se),一种天然矿物质微量元素,是硒蛋白的重要组成部分,在抗氧化防御中起着重要作用。谷胱甘肽过氧化物酶(GPx)的活性,一种高效的抗氧化酶,与Se的存在密切相关。Se的这些特性可能潜在地适用于改善运动表现和训练恢复。我们系统地搜索已发表的研究,以评估补充硒对抗氧化防御系统的有效性,肌肉性能,激素反应,以及身体活跃的个体的运动表现。我们使用系统审查和荟萃分析(PRISMA)指南的首选报告要素,并在SCOPUS中进行搜索,WebofScience(WOS),和PubMed数据库,以确定已发表的研究,直到2020年3月。系统评价将原始研究与随机对照交叉或平行设计相结合,其中将每天服用一次的硒摄入量与相同的安慰剂条件进行比较。没有对进行的体育锻炼类型进行排除,性,也不是参与者的年龄。在搜索中确定的150篇文章中,6符合标准,并被纳入系统评价。使用McMaster关键审查表评估研究的方法学质量。口服硒补充剂180µg/天或240µg/天(硒代蛋氨酸)和200µg/天(亚硒酸钠),血浆中脂质过氧化氢水平显着降低,GPx增加,红细胞,和肌肉。对运动表现没有显著影响,睾酮激素水平,肌酸激酶活性,和运动训练对氧化酶活性或肌纤维型肌球蛋白重链表达的适应。此外,硒补充对慢性和急性运动中的线粒体变化具有抑制作用。总之,使用硒补充剂对有氧或无氧运动表现没有益处,但可以防止高强度和高容量训练的运动员缺乏硒。最佳的硒血浆水平对于最大程度地减少慢性运动引起的氧化作用和调节运动对线粒体变化的影响可能很重要。