Commentary: Metabolomics-Based Studies Assessing Exercise-Induced Alterations of the Human Metabolome: A Systematic Review - Castro, Alex; Duft, Renata Garbellini; Zeri, Ana Carolina de Mattos; Cavaglieri, Claudia Regina; Chacon-Mikahil, Mara Patrícia Traina (Frontiers in Physiology, 2020)