Monday, May 30, 2011

Do You Burn As Much Fat with Two Small Workouts As One Big One?

Happy Memorial Day, readers!

Today's question is a bit of a controversial one amongst dieters and those exercising for fat loss.  This question is, will a person burn the same amount of body fat by doing two small workouts instead of one big one?  Let's look at an example, below:

John Doe normally does 60 minutes of cardiovascular exercise each day.  He is considering splitting this into two 30 minute workouts.  Will John burn the same amount of fat this way?

The answer?  John will  likely burn about the same number of calories in both scenarios.  And, by splitting the workout into two smaller workouts, he will get added health benefits, improved post-exercise metabolic factors, and will generally reduce feelings of hunger more effectively than with his current hourlong exercise session.  However, there is a big downside...

After roughly 20-30 minutes of cardiovascular exercise at the appropriate intensity for fat loss, a person starts to burn a higher percentage of calories from stored fat.  You see, when you train your cardiovascular energy system, you don't burn every calorie from stored fat.  A bout that burns 1000 calories will not burn all 1000 calories from fat, but after 20-30 minutes, that percentage of calories burned from fat vs those burned from other sources will be higher and higher.  The story gets better:  After about 45 or 50 minutes, we'll see an even higher percentage of calories burned being stored from fat, and fewer and fewer from stored glycogen.

So, what does this mean for John Doe?  Absolute, maximum fat calories will be more greatly burned in the longer sweat-session than in the two shorter sessions, combined.  If John's sole aim is to burn as much body fat as possible, then he should stick to his current hourlong exercise session.  But, if John is bored with his routine and seeking a change that will still burn a great number of calories (and, generally, a decent percentage of those calories from stored fat), then splitting up his workout may be a good idea to avoid boredom and eventual burnout.  And again, the health benefits and metabolic benefits are often improved by exercising more frequently.

Do you have a question for an exercise physiologist from Perfect Personal Training?  We love to help!  Just post a comment below or call 877-698-3648 with your question, and we'll give you an in-depth and well-researched answer.  For more continued and personalized advice, we recommend working with a degreed and top-certified Perfect Personal Trainer.  Thank you for reading, and have a great new week!

* The Perfect Fathers' Day gift:  In-Home Exercise & Nutrition  *