Association between skeletal musce metabolomics profile and cardiorespiratory fitness in young men

Abstract

High cardiorespiratory fitness levels (CRF) are strongly associated with reduction of risk of all-cause and cardiovascular disease mortality. CRF can be assessed by maximal oxygen uptake (VO2MAX) or maximal power output (MPO). Skeletal muscle is the main organ responsible for peripheral adaptations related to CRF improvement. In this sense, metabolomics has been pointing out as a potential tool to identify muscular metabolic signature in response to exercise and different phenotypes. Therefore, this study aimed to investigate metabolites in human skeletal muscle associated with CRF. Participated in this study 70 sedentary young men (18-30 years old). Vastus lateralis muscle biopsies were collected at fasting state (12 h). After 72 h, CRF was assessed by MPO, obtained during a maximal incremental test performed until voluntary exhaustion in cycle ergometer, followed by re-test 48 h later. Skeletal muscle samples were analysed through metabolomics (H1 NMR spectroscopy). Associations of baseline metabolites with MPO were explored via three analytical strategies: (1) correlations with gains in MPO; (2) significant difference between groups of and Low CRF and High CRF; and (3) metabolite contribution to significant pathways related to MPO. The significance level was P < 0.01 or false discovery rate of 0.1. From 70 identified metabolites, only Formate and NADP+ were supported by the three levels of evidence. Intrinsic CRF levels are associated with higher baseline metabolities.