Expert: Daphne E Brown MS CPRP - 5/31/2004

Question
Dear Ms Brown,
           I was hoping you could help me in deciding the best approach to exercise for weight loss. I know that my target heart rate for fat loss is about 140. I can reach that easily jogging at 5mph on a flat plane with my treadmill. I have also tried raising the platform to an incline of 15 inches and walking at 3mph my heart rate was at 165. Needless to say it was more difficult. My question is which exercise burns more fat?
                      Respectfully yours,
                      Pablo Callejas

Answer
**suggestions offered here may or may not help you.  Please contact your physician when adding or changing an exercise/nutrition regimen**

HI Pablo.
Keep in mind.  ALL CARDIOVASCULAR EXERCISE UTILIZES FAT STORES (burning fat).  The difference between low intensity cardiovascular exercise and higher intensity cardiovascular exercise is the RATE at which calories are burned and where more calories are taken from (either the blood stream or from fat stores).  Are you with me so far??

Way back in the late eighties/early nineties, there was some research done to determine what percentage of fat stores were burned.  For most people, the harder and longer your cardiovascular workout is, the higher the percentage of CARBOHYDRATES are burned.  Needless to say, some really slick marketers said, "AH HA! We can tell people that if they don't work as hard or as long, they will burn more fat".  

If you think about it, this sounds really silly.   If I am working at a high heart rate for a long bout of time, say maintain my heart rate 165 for 20 minutes as opposed to 20 minutes at 140 heart rate, I will burn more calories, RIGHT?  The only difference is that a higher percentage of those calories will come from fat if I exercise at 140.  BUT I will BURN MORE FAT CALORIES working harder, even though the PERCENTAGE is LOWER at 165 bpm.  Does that make sense??  Anyway, there is NO SUCH THING as a "FAT BURNING ZONE".

Back to your question.  I can't really tell you accurately, which exercise makes you burn more fat because you haven't given me specifics (age, fitness level, medical/physiological issues, etc.).  I would guess to say the latter, where your heart rate goes to 165 bpm.  But if 140 bpm is part of your THR, by all means, exercise at that rate.  YOU WILL STILL "BURN" FAT!!  Fat calories will just be a higher percentage of the total number of calories that you burn.

Hope this helps, and DON'T BE FOOLED BY THE HYPE!!  Please feel free to check with other allexperts to get their take on it.  

Congratulations on a healthy lifestyle!!
Sincerely, Daphne