
Originally Posted by
phate
close but not quite, you don't have to completely deplete glycogen stores to burn fat during cardio, your body will burn a percentage of fat, glycogen, and muscle(via gluconeogenesis) during cardio and that percentage depends on alot of variables such as, current glycogen storage state, intensity of cardio, duration of cardio, etc...
performing aerobic cardio on an empty stomach will shift that percentage in favor of fat, meaning you will burn more calories from fat, because of decreased glycogen stores and the fact that fat burning is best done in an oxygen and H2O saturated environment(yes that means stay hydrated as well)