AUTHOR=Jasker Bryan , Dodd Daniel , Peek Clara B. , Griffith Garett J. TITLE=Development of the MetFlex Index™: associations between cardiometabolic risk factors and fitness using a novel approach with blood lactate JOURNAL=Frontiers in Physiology VOLUME=Volume 16 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2025.1546458 DOI=10.3389/fphys.2025.1546458 ISSN=1664-042X