Lipid metabolism during exercise I: Physiological and biochemical characterization of normal healthy male subjects in relation to their physical fitness

On the basis of maximal oxygen uptake (\(\dot V\)O2 max) 18 normal, healthy men were divided into two groups of equal size: moderately trained subjects (MTR) each having \(\dot V\)O2 max below 65.0 ml·min−1·kg−1 body weight (54.0±8.3) and well trained subjects (WTR), whose \(\dot V\)O2 max exceeded 65.0 ml·min−1·kg−1 body weight (69.2±4.1). The WTR group had slightly (non significant, n.s.) higher percentage of slow twitch, oxidative (SO) fibers in M. vastus lateralis and higher (n.s.) activities of cytochrome c oxidase (CytOx), succinate dehydrogenase (SDH), 3-hydroxyacyl-CoA-dehydrogenase (HADH), and citrate synthase (CS), while lactate dehydrogenase (LDH) activity was lower (n.s.). In th…