Does a 20-minute workout of cardio/aerobic exercise in the morning on an empty stomach cause fat loss faster than aerobic/cardio training later in the day?
Aerobic exercise uses a faster energy burning system, which is fueled by carbohydrates. The faster you’re moving, the more energy required, and that primary source of fuel is carbohydrate; so 20 minutes in the morning, although on and empty tank, the carbohydrates from the day before is being used and there is a lesser contribution of fat as fuel. So slowing down to a conversational jog or speed walk of 4 to 5 mph, will have a greater contribution of fat as fuel.
