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Background: Antioxidant supplementation has become a common practice among athletes to theoretically achieve a reduction in oxidative stress, promote recovery and improve performance. Objective: To assess the effect of antioxidant supplements on exercise. Methods: A systematic literature search was performed up to January 2019 in MEDLINE via EBSCO and Pubmed, and in Web of Sciences based on the following terms: “antioxidants” [Major] AND “exercise” AND “adaptation”; “antioxidant supplement” AND “(exercise or physical activity)” AND “(adaptation or adjustment)” [MesH]. Thirty-six articles were finally included. Results: Exhaustive exercise induces an antioxidant response in neutrophils through an increase in antioxidant enzymes, and antioxidant low-level supplementation does not block this adaptive cellular response. Supplementation with antioxidants appears to decrease oxidative damage blocking cell-signaling pathways associated with muscle hypertrophy. However, upregulation of endogenous antioxidant enzymes after resistance training is blocked by exogenous antioxidant supplementation. Supplementation with antioxidants does not affect the performance improvement induced by resistance exercise. The effects of antioxidant supplementation on physical performance and redox status may vary depending on baseline levels. Conclusion: The antioxidant response to exercise has two components: At the time of stress and adaptation through genetic modulation processes in front of persistent pro-oxidant situation. Acute administration of antioxidants immediately before or during an exercise session can have beneficial effects, such as a delay in the onset of fatigue and a reduction in the recovery period. Chronic administration of antioxidant supplements may impair exercise adaptations, and is only beneficial in subjects with low basal levels of antioxidants.

Background: Several drugs have been currently approved for the treatment of obesity. The pharmacokinetic of liraglutide, as well as the treatment of type 2 diabetes mellitus, have been widely described. Objective: To analyze the published systematic reviews on the use of liraglutide for the treatment of obesity. Methods: Systematic reviews were found out through MEDLINE searches, through EBSCO host and the Cochrane Library based on the following terms: "liraglutide" as major term and using the following Medical Subject Headings (MesH) terms: "obesity", "overweight", "weight loss". A total of 3 systematic reviews were finally included to be analyzed. Results: From the three systematic reviews selected, only two included the randomized clinical trials, while the third study reviewed both randomized and non-randomized clinical trials. Only one review performed statistical tests of heterogeneity and a meta-analysis, combining the results of individual studies. Another review showed the results of individual studies with odds ratio and confidence interval, but a second one just showed the means and confidence intervals. In all studies, weight loss was registered in persons treated with liraglutide in a dose dependent form, reaching a plateau at 3.0 mg dose, which was reached just in men. Most usual adverse events were gastrointestinal. Conclusion: More powerful and prospective studies are needed to assess all aspects related to liraglutide in the overweight and obesity treatment.