2. Materials and Methods
Skeletal muscle
Subjects and study protocol. The analysis described in this paper was part of the ‘iReAct’ (individual response to physical activity) study that has previously been described [Skeletal muscle biopsies. Before (pre) and two hours after the end of the reference training at baseline (post), fine-needle skeletal muscle biopsies were taken from the miR isolation. Total RNA, including small RNA species, was isolated from skeletal muscle tissue using the miRNeasy Micro Kit (Qiagen, Hilden, Germany), according to the manufacturer’s instructions.miR microarray analysis. Microarray analysis was carried out on samples obtained before and after the reference training from Reverse transcription and qPCR analysis. Reverse transcription was carried out using the miRCURY LNA RT Kits (Qiagen, Hilden, Germany), according to the manufacturer’s instructions. For qPCR analysis, the miRCURY LNA miRNA PCR Assays (Qiagen, Hilden, Germany) in conjunction with primers specific for individual miRs, were employed. Due to technical issues, qPCR analysis was not possible with samples of one of the subjects; so, only data from Statistical analysis. Statistical analysis was carried out using IBM SPSS Statistics Version 27.0 (IBM, Armonk, NY, USA). Data were tested for normal distribution using the Shapiro–Wilk test. For normally distributed data, mean values were compared between groups using t-tests for paired samples. Otherwise, Wilcoxon signed-rank tests were employed. Correlation analyses were carried out by means of the Spearman method, observing Cohen’s guidelines for evaluating the correlation coefficient r [KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis. KEGG pathway analysis was carried out using the TarBase v7.0 database within the online platform DIANA-miRPath v3.0 [