Thursday, October 1, 2009

Basal Metabolic Rate - Calculation

I don't remember which source this came from...but I believe it's from one of my  bariatric surgery workbooks.

BMR=Basal Metabolic Rate
This is the number of calories you burn in a day doing living activities (breathing, burping, passing gas, swallowing, ect).  To calculate this (roughly)

women:  BMR=655 + (4.35 X weight in pounds) + (4.7 X height in inches) - (4.7 X age in years)

men:  BMR=66 + (6.23 X weight in pounds) + (12.7 X height in inches) - (6.8 X age in years)

For me it would look like this:

655 + (4.35 X 180) + (4.7 X 65) - (4.7 X 44) = 1536

Take your BMR and apply it to the activity level below:

Sedentary lifestyle (little/no exercise) = BMR x 1.2
Light active lifestyle (light exercise/sport) = BMR X 1.375
Moderately active = BMR X 1.55
Very active = BMR X 1.725
Extra Active = BMR X 1.9

For me:

1536 X 1.2 (sedentary) = 1843
1536 X 1.375 (light activity) = 2112

This final calculation indicates the numbers of calories I need to take in to maintain my current weight at my current activity level. lose weight, I need to take in less than the 1843 (sedentary) or 2112 (light activity) calories.  Notice then, the more activity that you do, the more calories you need...even to lose weight!!  The bigger the calorie deficit, the faster you lose weight (it would stand to deduct)...however, we must use our heads (mine included...I don't practice what I always preach) and not undercut to many calories especially if you are involved in activities like cycling, spinning and running.

You also need to note that part of the BMR is based on your current weight, so as you lose weight, the equation needs to be revisited and adjusted.

I think this calculates a little bit high but it gives a rough estimate.  If anyone has further information, please feel free to share as I am not the end all in any subject.  This number seems to correlate well (BMR) to the scale I have at home that calculates this (although I don't know how it figures this).

Alright....enough for now! 


1 comment:

Anonymous said...

It's me again...I ran your numbers and they seem a bit "rough" to me. You can go to local fitness centers that will do a diagnostic test on you to determine exactly what your BMR is. The formula you wrote gives you a rough ballpark, but for $30 you can know exactly where you stand. With the drastic procedures youve had done and the abnormal activity you have this may be money well spent. The numbers I ran, I was off by 300 calories from a BMR diagnostic test I did several months ago If you take those 200-300 calories over each week over a month, this adds up to quite a difference. It seems like you've taken a lot of steps to lose weight and stay active. Why not take an additional step to know just exactly what your body is burning. It can be done and be pretty exact. This would give you your baseline you need.
I'm glad to see you admitted you were over reacting. This is what got you introuble. You need a systematic, delibrate and confident approach.

Keep posting and keep the faith...
there's nothing you can't do when you put your mind to it. Someone said that...I'm sure. Anyways...I'm out until next time.
Be Balanced (B.B.)