The Rating of Perceived Exertion is Able to Differentiate the Post-Matches Metabolomic Profile of Elite U-20 Soccer Players

The study aimed to assess the metabolic impact of elite Brazilian U-20 players using the rating of perceived exertion scale (RPE) to discriminate metabolomics sensitivity post-two soccer games separated by a short recovery interval. Urine was collected immediately and then 20 h after two soccer matches of elite Brazilian U-20 players. RPE was collected after games. The spectra were pre-processed using TopSpin®3.2 software. Chenomx®software was used to identify metabolites in the urine through the available database. The results showed that the metabolic pathways related to energy production, cellular damage, and organic stresses were changed immediately after the game. 20 h after the games, antioxidant and anti-inflammatory pathways related to cell recovery were identified (e.g., gallic acid, ascorbate, and betaine). The matrix of positive correlations between metabolites was more predominant and stronger after game 2 than game 1. T-distribution registered metabolites discriminated below and above 7 on the RPE scale. Athletes with higher RPE values showed a high metabolite profile related to muscle damage (e.g., creatine, creatinine, and glycine) and energy production (e.g., creatine, formate, pyruvate, 1,3 dihydroxyacetone) 20 h post-soccer match. There was a different metabolic profile between athletes with higher and lower RPE values. Metabolomics analysis made it possible to observe the metabolic impacts of energy production and muscular damage. RPE identified internal load changes within the group as a result of match intensity in soccer. The correlation matrix indicated a greater predominance of positive and strong correlations between metabolites in the second game compared to the first game.