Lactobacillus plantarum Supplementation on Sport Performance, Biomarkers of Intestinal Damage, and Oxidative Stress in Recreational Athletes

<b>Background:</b> In recent years, interest in probiotic supplementation has increased among athletes due to its potential benefits on sports performance. Thus, the aim of this trial was to investigate <i>Lactobacillus plantarum</i>'s effects on sports performance, intestinal damage, and oxidative stress biomarkers. <b>Methods</b>: Twenty-two physically active participants, nine females and thirteen males (age: 32.8 ± 5.2 years; height: 1.73 ± 0.1 m (meters); body mass: 72.2 ± 10.3 kg (kilograms) volunteered in this randomized, double-blind, placebo-controlled, parallel study. The participants performed a strenuous exercise session, and immediately after, their perceived exertion was assessed and blood samples were drawn to assess intestinal damage (IFABP: intestinal fatty acid binding protein) and oxidative stress (PC: protein carbonyls; TAC: total antioxidant capacity; total proteins; GSSG: glutathione disulfide; GSH: reduced glutathione and catalase). Twenty-four hours later, the participants ranked their recovery status and completed various sports performance tests: CMJ (countermovement jump), RAST (running-based anaerobic sprint), and YOYO IR1 (YOYO intermittent recovery test level 1). This was followed by a four-week supplementation period, in which the participants ingested one probiotic capsule per day containing 10 billion CFU (colony forming units) of <i>Lactobacillus plantarum</i> or a placebo capsule (dextrose). <b>Results</b>: The paired samples <i>t</i>-test revealed a significantly better result in the YOYO IR1 test in the probiotic group, while a significant reduction was observed in the TAC levels in the placebo group. <b>Conclusions:</b> The results suggest that <i>Lactobacillus plantarum</i> supplementation could increase YOYO IR1 sports performance test scores and may mitigate TAC value reduction.