Cardio is done to improve cardio vascular fitness and burn calories. It will HELP with a calorie deficit and for some that do a lot of cardio, allow one to eat more versus someone at the same weight who does little or no cardio at all.
Like all other physical activity, GLYCOGEN will be the first thing burned before fat is even touched (ratio will vary more to fat if duration extended and/or intensity is lower) so the addage that one
needs to do cardio to burn fat is a myth. You burn fat with a calorie deficit. Don't believe it? Do whatever cardio you want, but eat your TDEE. You'll more likely keep the same bodyfat percentage if you keep doing that.
A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 30 years and have studied kinesiology and nutrition