Fasted cardio is when you do your aerobic exercise session either first thing in the morning before eating anything or 3-4hrs after your last meal Some people believe this is a horrible idea as your body could potentially seek energy in your existing muscle mass. For much of the fitness community, retaining existing muscle mass is of paramount importance.
Others see fasted cardio as an opportunity to burn calories more likely to come from stored fat rather than carbohydrate either stored or in the blood. For the majority of the population burning fat is of paramount importance.
Who is right? The answer, like many topics in exercise physiology, is not so simple or universal. Whether or not fasted cardio is for you depends on your goals. If you currently have good body composition (i.e. Under 10-12% body fat for men, under 15-18% for women), fasted cardio may not be necessary as recovery from muscle building workouts is important and fasted cardio could compromise this. However it could still be beneficial as I will discuss in a sec. If you are overweight and your main objective is losing body fat then fasted cardio is a good way to optimize your time as fasted cardio will target fat stores easier. My advice when doing fasted cardio is to keep the intensity a bit lower than you would during a normal cardio session. The intensity should be very low between 120-130bpm for most people.
For anyone very concerned about burning muscle mass during these sessions, you could take 5-10g of branch chain amino acids with water before the session. To also enhance these sessions take some caffeine (in pill form to avoid calories). More about caffeine in future Training Tips.
Don’t forget! Just because you burn 300calories in your fasted cardio session doesn’t mean you can add 300cals to your breakfast! Your diet is the most important aspect of your fat loss plan!
Stay healthy y’all and Trust Your Struggle!