Fat Burning Heart Zone

Hi,

I am 30 years old male, 171 cm height and 84 kgs. BMI is around 29. I need to lose some weight. I have been doing walking exercise for last 2 months and have been keeping my heart rate at around 120 bpm. Then I climb 10 flight of stairs which raises my heart rate to 132 bpm. But this is momentarily only. I walk for 45 minutes, 5 days a week.

I just wanted to ask that if I want to lose weight, then am I keeping my heart rate in the right zone? I do not want to jog or run. Normal to brisk walking is all that I want to do.

[gymdandee]

The body does burn a higher percentage of calories from fat in the 'fat burning zone' or at lower intensities.  But, at higher intensities, you burn a greater number of overall calories which is what you should be concerned about when trying to lose weight. The chart below details the fat calories expended by a 130-pound person during cardio exercise:

Low Intensity - 60-65% MHR High Intensity - 80-85% MHR
Total Calories expended per min. 4.86           6.86
Fat Calories expended per min.        2.43                 2.7
Total Calories expended in 30 min. 146                206
Total Fat calories expended in 30 min.  73                  82
Percentage of fat calories burned 50%         39.85%

From The 24/5 Complete Personal Training Manual, 24 Hour Fitness, 2000

In this example, the person burns more total calories and more fat calories at a higher intensity. This isn't to say that low intensity exercise doesn't have it's place. In fact, endurance workouts should be a staple of a complete fitness program along with shorter, higher intensity workouts or even interval workouts which are a great way to burn calories and build endurance.  To figure out your own intensity levels, start by calculating your target heart rate zone.

In order to figure out which zone you're in, you first need to figure out what your own target heart rate is. You can do this by using the Karvonen Formula. You can also use any number of target heart rate calculators to get your heart rate zone, but many of them do not incorporate your resting heart rate (which makes it a bit more accurate).

Below is an example of the Karvonen formula for a 23 year old person with a resting heart rate of 65 beats per minute (to get your resting heart rate, take your pulse for one full minute.)

220 - 23 (age) = 197
197 - 65 (resting heart rate) = 132
132   65% (low end of heart rate) OR 85% (high end) = 85.8 OR 112.2
85.8 + 65 (resting heart rate) = 150 112.2 + 65 (rhr) = 177
The target heart rate zone for this person would be 150 to 177

For this person to work in his 'fat burning' zone, he would need to stay around 150 beats per minute or lower. To work within his 'cardio' zone, he would need to work at 150 bpm or higher.  

[mindforge]

Won't losing fats result in weight loss too? I am not a "veteran exerciser" and don't want to push a lot. I need to lose fats' weight first and then move on to something vigorous.

[gymdandee]

Buy a pedometer and take 10,000 steps per day to help you lose weight

[Dr Arora]

Hi, your BMI should be less than 25 in order to make it normal. You are in overweight category. Your max heart rate could be approx 220 minus your age. Your target HR would be around 150-160 for your age. You should achieve your target heart rate slowly. The fact is that brisk walking will be sufficient to loose weight buy slowly. Until you achieve target heart rate you would not loose weight more than a slow pace. Please add some jogging to your brisk walking schedule. Regards

[mindforge]

Thanks Doctor. I am trying to up my heart rate. Now I am training at 120 - 132 bpm, which is around 60-70% of my max heart rate. Once I become fitter, I will try to touch 140-150 bpm. Anyways, I also have hyperthyroidism (current euthyroid after medications). This kind of helps in metabolism. On my last weight check-up, my weight has come down by 2 kgs (Around 4-5 lbs) in 2 months. I can accept this weight change. Gradual weight change is better for me than sudden as it will disturb my thyroid levels.

[djole123]

Fat - burning zone is a myth. There are a lot references witch confirm that aerobic training does not improve fat loss.  My philosophy for fat loss is - train to keep muscle mass - eat well to loose fat. Also the human body is not a calorie-meter. A lot overweigth people eat low amounts of food.