Influence of nutrition pattern on exercise performance, inflammation and muscle damage biomarkers in a non-trained healthy young cohort

Background. Physical exercise induces muscle damage and inflammation, particularly in non-trained individuals, leading to reduced performance. This study explores the influence of dietary patterns on exercise outcomes and systemic physiological biomarkers in this population. Methods . This is an observational study with a transversal design complemented by prospective short-term follow-up to assess the effect of diet on exercise-induced inflammation and muscle damage. Recreationally active volunteers (45 females and 33 males) answered a food frequency questionnaire corrected by FETA. A step-exercise was performed until exertion and plasma samples were obtained before (basal) and 2h and 48h post-exercise. Muscle damage enzymatic biomarkers (creatine kinase, CK; lactate dehydrogenase, LDH activities) were evaluated through commercial kits and spectrophotometry, while cytokines (IL-1a, IL-1b, IL-6, MCP-1, TNFa, IL-1ra and IL-10) were assessed by multiplex ELISA. Principal components analysis (PCA) and structural equation models were used to evaluate associations between variables. Results . A dietary pattern characterized by higher intakes of proteins, fats, and carbohydrates positively influenced physical performance through muscle mass. PCA evidenced 2 inflammation scores (PC1 and PC2) which explained most of cytokine´s variance with opposing correlations with nutrients. PC1 had a negative correlation with proteins, unsaturated fats, folates and vitamin D, while PC2 had positive correlations with simple sugars, saturated fats, insoluble fiber and folates. Exercise volume influenced early systemic inflammation but had no effect on CK or LDH. No sex differences, other than muscle mass, were detected in the population. Conclusions . In non-trained population, nutrient-rich dietary patterns, particularly those high in healthy fats, enhance exercise performance, and have an indirect impact on inflammation, without affecting muscle damage biomarkers or showing sex-based differences.