Description:Hypoxia-inducible factor (HIF)-1a is continuously synthesized and degraded in normoxia, whereas during hypoxia, HIF1a stabilization restricts cellular oxygen utilization. Less is known about HIF1a function(s) and sex-specific effects during normoxia in the basal state. Since skeletal muscle is the largest protein store in mammals and protein homeostasis has high energy demands, we determined HIF1a function at baseline during normoxia in skeletal muscle with the use of untargeted metabolomics.