Why does varied speed running burn fat?
if you are talking about high intensity interval training, than it burns fat because it elevates your heart rate and because during the intense bouts, you are giving it your all, whether your “all” is my walk, or you are faster than michael johnson, you are giving it your best sprint and ayt the end, you should be outta breath. so, it should give you an afterburn effect unlike the monotonous slow steady long duration bull**** jogging or walking. you might be burning alot less or maybe equal to what you do doing the long duration jogs but you get an afterburn efftect and it is usually shorter. a HIIT session should be 10-20 minutes long depending how hard you work or your goals. also, HIIT doesnt use fat as a main source of energy. because you are “intensly” running, your body uses carbs stored in muscles as main source of energy. so the long and slow steady jogs uses mainly fat and some carbs for energy but you get no after burn effect and the loads of calorie burning slows down to reg
