I think that the Alpert number may not be right if you are on a Low Carbohydrate diet.
The Alpert number is the maximum rate of fat oxidation from a relatively moderately active person (Hypophagia – How much fat can I lose in a day?). It occurred to me that I can check this number from my own VO2max test.
- Looking at the REE at rest (REE from VO2max) it shows 2.16 kCal/min.
- From my Bod Pod results (Overshot My Recomp Goals – Part 1) my fat mass is 12.3 lbs.
- Multiplying my fat mass times the Alpert number is 381.3 kCals/day. That’s 15.88 kCal/hr or 0.26 kCal/min.
Yet, my REE was 2.1 kCal/min at and RER of 0.73 (90% fat) which is 1.9 kCal/min from fat oxidation. Flipping the number around that’s 1.9 times 60 times 24 = 2736 kCal per day from fat.
The smallest number I saw in the resting period was 1.209 kCal/min or 1740 kCal/day. dividing 1740 number by my fat weight in lbs is 141 kCal per lb of fat mass. That’s quite a bit more than the Alpert number.
The Minnesota Starvation (Ancel Keys) data was the basis of the Alpert number. Perhaps the difference is in the idea that I am not actually in starvation? And the Minnesota Starvation subjects were fed carbohydrates in their diet.
The Alpert number pretty closely matches my own experiences in Protein Sparing dieting.