Anyone interested in losing body fat who is not lifting weights should first take up a regimen of bodybuilding.
Worrying about details such as whether to do cardio fasted or fed is pointless if you’re not even taking advantage of the major body- composition improving benefits of weight training!
A common concern about doing cardio in the fasted state, especially if it’s done with high intensity, is the possibility of losing muscle. After an overnight fast, glycogen, blood glucose and insulin are all low.
Unfortunately, it may also be an optimum environment for burning muscle because carbohydrate fuel sources are low and levels of the catabolic stress hormone cortisol are high. It sounds like morning cardio might be a double-edged sword, but there are ways to avert muscle loss.
All aerobic exercise will have some effect on building muscle, but as long as you don’t overdo it, you shouldn’t worry about losing muscle. It’s a fact that muscle proteins are broken down and used for energy during aerobic exercise. But you are constantly breaking down and re-building muscle tissue anyway.
This process is called “protein turnover” and it’s a daily fact of life. Your goal is to tip the scales slightly in favour of increasing the anabolic side and reducing the catabolic side just enough so you stay anabolic and you gain or at least maintain muscle.
First , avoid excessive cardio. I suggest limiting your cardio on an empty stomach to 45 minutes, and then it would be “highly unlikely that amino acids will be burned as fuel.” also “a strong cup of coffee should facilitate a shifting to burn more fat and less glycogen. If you can spare glycogen, you’ll ultimately spare protein too.”
Second, give your body the proper nutritional support. Losing muscle probably has more to do with inadequate nutrition than with excessive aerobics. Provide yourself with the proper nutritional support for the rest of the day, including adequate meal frequency, protein, carbohydrates and total calories, and it’s not as likely that there will be a net loss of muscle tissue over each 24-hour period.
Third, keep training with relatively heavy weights, even during a fat loss phase. Using light weights and higher reps thinking that it will help you get more “cut” is a mistake: What put the muscle on in the first place is likely to help you keep it there.
Still petrified of losing your hard-earned muscle, but you’d like to take advantage of the fat-burning and metabolism-boosting effects of morning cardio? One strategy many bodybuilders use is to drink a protein shake or eat a protein only meal 30 minutes or so prior to the morning session. The protein without the carbs will minimize the insulin response and allow you to mobilize fat while providing amino acids to prevent muscle breakdown.
In conclusion, it seems that A. M. cardio has enough indisputable benefits to motivate most people to set their alarms early.
But let’s talk bottom line results here: Does doing morning cardio in a fasted state really result in more “real world fat loss” than cardio performed at other times of the day or after eating? I have to believe it does. Common sense, research and experience from many bodybuilding competions and success stories all tell me