INTRODUCTION The design of training programs for football players is not straightforward due to intra- and inter-individual variability that leads to different physiological responses under similar training loads. OBJECTIVE To study the association between the external load, defined by variables obtained using electronic performance tracking systems (EPTS), and the urinary metabolome as a surrogate of the metabolic adaptation to training. METHODS Urine metabolic and EPTS data from 80 professional football players collected in an observational longitudinal study were analyzed by ultra-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry and assessed by partial least squares (PLS) regression. RESULTS PLS models identified steroid hormone metabolites, hypoxanthine metabolites, acetylated amino acids, intermediates in phenylalanine metabolism, tyrosine, tryptophan metabolites, and riboflavin among the most relevant variables associated with external load. Metabolic network analysis identified enriched pathways including steroid hormone biosynthesis and metabolism of tyrosine and tryptophan. The ratio of players showing a deviation from the PLS model of adaptation to exercise was higher among those who suffered a muscular lesion compared to those who did not. CONCLUSIONS There was a significant association between the external load and the urinary metabolic profile, with alteration of biochemical pathways associated with long-term adaptation to training. Future studies should focus on the validation of these findings and the development of metabolic models to identify professional football players at risk of developing muscular injuries.

中文翻译：

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尿液代谢组学分析，用于监测职业足球运动员的内部负荷。

引言由于足球运动员内部和个体之间的差异性导致在相似的训练负荷下产生不同的生理反应，因此针对足球运动员的训练计划的设计并不简单。目的研究外部负荷（由使用电子性能跟踪系统（EPTS）获得的变量定义）与尿液代谢组之间的关联，以替代代谢适应训练。方法采用观察性纵向研究收集的80名职业足球运动员的尿液代谢和EPTS数据，通过超高效液相色谱与电喷雾电离四极杆飞行时间质谱联用，并通过偏最小二乘（PLS）回归进行评估。结果PLS模型确定了类固醇激素代谢物，次黄嘌呤代谢物，乙酰化氨基酸，苯丙氨酸代谢的中间产物，酪氨酸，色氨酸代谢产物和核黄素是与外部负荷相关的最相关变量。代谢网络分析确定了丰富的途径，包括类固醇激素的生物合成以及酪氨酸和色氨酸的代谢。遭受肌肉损伤的人与未遭受肌肉损伤的人相比，表现出偏离PLS适应运动模型的运动员比例更高。结论外在负荷与尿代谢谱之间存在显着关联，其生化途径的改变与长期适应训练有关。