Morning Cardio Controversy: Does cardio in the morning on an empty stomach really burn more fat?

I read your article about doing cardio in the morning to lose more fat, but I recently read another article which said that cardio in a fasted state causes the body to go into survival mode and save the fat - which means you burn muscle. Both theories sound right to me depending on the angle I look from. Any thoughts?

Answer:
First of all, let me say that the fasted cardio in the morning theory IS controversial, and everything I write about it is strictly my personal opinion. However, I think my opinion is probably worth something because it's founded on 20 years of experience - both academic and "in the trenches" experience.

You're right that both theories have merit. Muscle loss could be an issue depending on the intensity and duration of your morning cardio session as well as your nutritional status. But why worry about it or sit around a table and argue about it? Why not tackle the issue of muscle loss head on? Simply measure your body fat and calculate your lean mass, then you'll know if you're losing muscle or not. Why guess?

Any discussion of muscle loss from cardio is strictly academic, UNLESS YOU ARE ACTUALLY MEAUSURING IT!!!!

Does morning cardio burn a greater amount of fat than cardio done at other times? Well, the bottom line when evaluating any training or nutritional practice is results - period! I don't care what any "expert" says or what any research study says - I measure my results carefully and if I'm getting results training or eating in a certain manner, I'm going to keep doing it. And so should you. I suggest you base all your decisions about your training and nutrition on results and results alone and forget about all these "gurus" arguing back and forth about who is right and wrong. You can't argue with results.

I Don't consider morning cardio an absolute necessity. I just consider it one aspect of your training program that you can experiment with to see if it produces better results for you. Speaking of results, I've reached 3.4% body fat with no drugs and almost no supplements and part of my strategy on "cutting" programs has always been morning cardio. My clients have also achieved great results. The Body for Life program (which also recommends early morning cardio), has also gotten great results for many people (and Bill Phillips is no slouch in the physique department himself).

Although most academic types don't believe in the morning cardio theory, there's plenty of research that supports it. I found it especially interesting that Dr. Mel Siff, Author of Facts and Fallacies of Fitness and moderator of the Supertraining Yahoo forum, included a brief section in his book called "Slim Before Breakfast." He quoted a study lending support to the a.m. cardio theory. Dr. Siff wrote;

"A study carried out at Kansas State University (Wilcox, Harford & Wedel Medicine & Science in Sports and Exercise, 17:2, 1985), indicates that a kilogram of fat will be oxidized sooner when exercising in the fasted condition in the morning than when doing the same exercise in the afternoon. By measuring respiratory gas exchange, caloric expenditure, and carbohydrate and fatty acid metabolism, these researchers showed that the mass of fat burned during aerobic exercise amounts to 67% of the total energy expenditure achieved when the same exercise is done later in the day or in the fed state."

The reason I mention this is because Dr. Siff wasknown as one of the most logical and scientific minded (skeptical) experts in the field.

Cardio and weightloss are covered in detail in my 340 page ebook Burn the Fat, Feed the Muscle (BFFM)