4.9. Statistical Analysis
For all variables, the assumption of normality of data distribution and homogeneity of variances were checked using the Shapiro–Wilk test and Levene test, respectively. To compare participant characteristics at baseline, one-way analysis of variance (ANOVA) was used. For the metabolomics data, all variables were Box-Cox transformed [After, to identify meaningful metabolic pathways influenced by IMT, all metabolites that showed significant main effects and interactions in LMM were listed for a metabolite set enrichment analysis (MSEA) based on established human metabolic pathways from the Small Molecule Pathway Database (SMPD) library. This analysis employed an algorithm for over-representation analysis and hypergeometric testing to assess whether specific metabolite sets were represented more than expected by chance within the given compound list [Univariate analysis was conducted using PASW statistics software version 25.0 (SPSS, Chicago, IL, USA), pathway analyses were performed using the MetaboAnalyst 5.0 webtool, and figures were elaborated using GraphPad Prism 9 or MetaboAnalyst 5.0.