I have a friend, let’s call him Moe. Moe is 30 years old. Moe is not a low carb dieter. Moe has been inconsistent in his training for the past two years. Moe has recently taken up running again. Moe’s MAF number is 180 – 30 -5 = 145. Use the Heart Rate Calculator to see the numbers.
Moe took the same Vo2max test that I did at WVU Human Performance Lab. Here’s Moe’s fat/carb oxidation curves.
If Moe does MAF Heart Rate training at 135-145 is heart rate would be approaching his cross-over of fat/carbs kcals per minute. However, Moe wants to burn the maximum number of calories so he runs near his max heart rate. When he runs at a high heart rate, Moe is burning carbs and not much fat. Moe could adopt a low carb diet and run slower with the positive effect of increased fat loss and no need to burn carbohydrates.
Me vs Moe
I am 28 years older than Moe. Here’s my curve with my MAF Heart Range noted.
My max fat oxidation rate is around 11 kcal/sec. Moe’s max fat oxidation rate is around 9 kcal/sec. Moe’s max carb oxidation rate is 16 kcal/min vs my 24 kcal/min.