Cardio Smart Watch

Short answer, the body fat of the person will be the main determinant of whether fasted cardio is important or not.

There are 3 primary steps in fat loss.

Mobilization, transport, oxidation.

Mobilization refers to actually getting stored fat (specifically fatty acids) out of the fat cell.

Transport refers to the actual transport of fatty acids (bound to albumin) within the bloodstream; this step can be an issue when folks are dealing with stubborn body fat (such as lower ab/low back fat in men and hip/thigh fat in women); blood flow is impaired in those areas.

Finally is oxidation which is the actual burning of fatty acids within tissues such as skeletal muscle, liver, and heart.

Individuals at the very end So, short answer, no it doesn’t matter if you do it fasted or not because the majority of the population is between very lean and obese, from about 15-35% body fat in men and 20-40% body fat in women there are really no issues. Mobilization is usually not a problem since the body hasn’t started to fight back, transport isn’t an issue since stubborn fat isn’t being targeted, and oxidation is rarely a problem since the defects show up at the extremes of obesity generally aren’t present of both spectrums will have their own set of issues with each of these steps but that is a topic for another time.

Calories in versus out matters more in this case.