Research Corner - Q&A What is the Fat Burning Zone? by Dr. Rob Orr | Date Released : 30 Apr 2005 0 comments Print Close Question: What exactly is the Fat Burning Zone? Answer: The Fat Burning Zone is claimed to be the optimal training intensity for burning fat: an intensity between 60 and 75 percent of your predicted maximum heart rate (208 minus Age (0.7)). The theoretical reason behind this argument is based on a principal whereby, the lower the exercise intensity, the greater the percentage of energy requirements is met by fat. Inversely, in the Cardio Training Zone (between 70 and 85 percent, depending on references), the main energy supply comes from carbohydrates. The reason for the shift is due to difficulty in obtaining, transporting and utilizing sufficient oxygen at higher intensities to metabolize fat (which has a higher hydrogen component than carbohydrates), leading to the use of carbohydrates as a preferred fuel source. This is the portion of information most often used to justify low intensity Fat Burning Zone training. Consider this: When sleeping, over 90 percent of energy used comes from fat stores. With this in mind, why train at all? Herein lies the flaw in the "fat burning zone" argument - the disregard for the total amount of calories consumed. Let us say that Subject A ran or walked at 65 percent (in his Fat Burning Zone) for 30 minutes and burned 400 calories; 60 percent of these calories are made up from fat, which means that 240 calories of the overall 400 calories burned are from fats. However, if this same person trained in his Cardio Zone at 75 percent and burned an estimated 700 calories, the now lower 40 percent of fat calories burned equals 280 calories with the overall total being 700 calories burned. This shows that not only are more fat calories consumed but so too are the total amount of calories. Remember: a key concept behind fat loss is in creating a calorie deficit (more energy out than in). There are benefits of low intensity training, however. If you were to train for longer in the Fat Burning Zone (compared to Cardio Zone), a greater percentage of fat would be burned from higher total values. For example, if Subject A were to instead run or walk at 65 percent for an hour, the total calories burned would equal 800, with fat making up 480 calories. Furthermore, injury or a poor fitness base may mean that high intensity training is inappropriate at a given stage in a training program. Conversely, higher intensity training has benefits in terms of a proposed increase in metabolic rate and hunger suppression following high intensity sessions. So which to use? As with any training program, the purpose of the training and history of the client are paramount considerations. Applying the basic concept of periodization to fat loss, low intensity exercise of long duration can be used to develop an initial training base (and anatomic adaptation) with gradual progression to higher intensity, shorter duration sessions. If already fit, periodized cycles can be shorter (e.g., two weeks low intensity, one week medium intensity, one week very high intensity) or even interspersed in a single session (e.g., 10 minute run at 80 percent followed by 30 minute cycle at 60 to 70 percent). So forget the hype, stick to the facts. Fat loss is simple: input versus output. Back to top About the author: Dr. Rob Orr Dr. Rob Orr joined the Australian Army in 1989 as an infantry soldier before transferring to the Defence Force Physical Training Instructor (PTI) stream. Serving for 10 years in this stream, Rob designed, developed, instructed and audited physical training programs and physical education courses for military personnel and fellow PTIs from both Australian and foreign defence forces. Rob subsequently transferred to the physiotherapy stream where his role included the clinical rehabilitation of defense members and project management of physical conditioning optimisation reviews. Serving as the Human Performance Officer for Special Operations before joining the team at Bond University in 2012, Rob continues to serve in the Army Reserve as a Human Performance Officer and as a sessional lecturer and consultant. Rob is also the co-chair of Tactical Strength and Conditioning (TSAC) – Australia. Rob’s fields of research include physical conditioning and injury prevention for military and protective services from the initial trainee to the elite warrior. Generally focussing on the tactical population, Rob is actively involved in research with the Australian and foreign defense forces, several police departments (both national and international), and firefighters. The results of Rob’s work and academic research have been published in newspapers, magazines and peer-reviewed journals and led to several health and safety awards. In addition, Dr. Orr serves as the section editor for the Australian Strength and Conditioning Journal – TSAC Section and the shadow editor for the National Strength and Conditioning Association (NSCA) TSAC Technical Report. Rob is regularly invited to deliver training workshops and present at conferences both nationally and internationally. Full Author Details Related content Content from Dr. Rob Orr Does Muscle Weigh More Than Fat? Heath Williams | Articles Calorie Burn Before or After Eating Dr. Rob Orr | Articles BMR and Obesity Dr. Rob Orr | Articles Aerobic vs. Weight Training Jeff Thaxton | Articles Safe Weight Loss Guidelines Amy Moran | Articles Weight Loss Difficulties Craig Burris | Articles Line drills part 2 Dr. Rob Orr | Articles Line drills part 1 Dr. Rob Orr | Articles Injuries Typical of Tactical Populations and Their Recovery Dr. Rob Orr | Articles Optimizing the Conditioning of New Tactical Trainees Dr. Rob Orr | Articles Muscle Contractions, Part 3: How to Use Them - Practical Dr. Rob Orr | Articles Muscle Contractions, Part 2: How to Use Them - Theory Dr. Rob Orr | Articles Muscle Contractions, Part 1: Different Types Dr. Rob Orr | Articles Treadmill Running - A Review Dr. Rob Orr | Articles The Functional Continuum Dr. Rob Orr | Articles The Art of Spotting - Part 1 Dr. Rob Orr | Articles Surfer with Scoliosis Dr. Rob Orr | Articles Weighted Vests Dr. Rob Orr | Articles Group Power Classes Dr. Rob Orr | Articles Resistance Training Programs – Part 2 Dr. Rob Orr | Articles Resistance Training Programs – Part 1 Dr. Rob Orr | Articles Healthy Weight Gain Dr. Rob Orr | Articles Calorie Burn Before or After Eating Dr. Rob Orr | Articles BMR and Obesity Dr. Rob Orr | Articles Line Drills - Part 2 Dr. Rob Orr | Articles Best Time of Day to Exercise Dr. Rob Orr | Articles Line Drills - Part 1 Dr. Rob Orr | Articles Paddle Board Racing Dr. Rob Orr | Articles Optimizing Workout Routines Dr. Rob Orr | Articles Hypoxic Work in the Pool Dr. Rob Orr | Articles Run and Bike Cross Training Dr. Rob Orr | Articles Programming for Partner Training Dr. Rob Orr | Articles Periodized Programs - Part 3 Dr. Rob Orr | Articles Blurred Vision with Cardio Dr. Rob Orr | Articles Periodized Programs - Part 2 Dr. Rob Orr | Articles How Fast Can the Heart Beat? Dr. Rob Orr | Articles Floaters and Sinkers in Water Dr. Rob Orr | Articles Periodized Programs - Part 1 Dr. Rob Orr | Articles Karvonen vs. 220–Age Heart Rate Training Dr. Rob Orr | Articles Fartlek Training for Group Exercise Dr. Rob Orr | Articles Walk Test on Treadmill Dr. Rob Orr | Articles Weights vs. Cardio for Weight Loss Dr. Rob Orr | Articles What is the Fat Burning Zone? Dr. Rob Orr | Articles Treadmill vs. Land Walking/Running Dr. Rob Orr | Articles Max Heart Rate Testing Dr. Rob Orr | Articles Running/Walking vs. Cycling, Swimming Comparison Dr. Rob Orr | Articles High Altitude Hiking Dr. Rob Orr | Articles Metabolic Conditioning Dr. Rob Orr | Articles Fartlek Training for Group Exercise Dr. Rob Orr | Articles Circuit Training Variations - Part 2 Dr. Rob Orr | Articles Circuit Training Variations - Part 1 Dr. Rob Orr | Articles Lactic Acid and Fat Burning Dr. Rob Orr | Articles Energy Expenditure for Running Dr. Rob Orr | Articles Designing Effective Circuits Dr. Rob Orr | Articles The Functional Continuum Dr. Rob Orr | Articles Heat Balance Dr. Rob Orr | Articles Anaerobic and Aerobic Conditioning Dr. Rob Orr | Articles Swimming Dr. Rob Orr | Articles Please login to leave a comment Comments (0) Back to top