Eating "under BMR"

[GoldenArmKid]

Something has kind of bothered me for a bit. When on a cut people usually reccomend that you eat about 200-500 calories under your BMR. But is this with activity levels factored in?

For instance if my BMR is at 1800 or something am I eating about 200 calories under that on a cut?

OR

With activity factored in (making my daily required calories about 2150 at worst/sedentary)?

[Ryan314]

It's BMR plus your activity factor.

BMR alone is what you'd burn if you were sedentary all day long.

[ajm422]

Basal Metabolic Rate (BMR) is what your body uses to keep yourself alive. Things like your heart beating (while sedentary), breathing (while sedentary), thinking (while watching reality TV), and all other background processes where your body is not doing anything. On top of this, you have to factor in activity, the thermic effect of food, etc. You're looking for Total Energy Expenditure (TEE). See this sticky for a complete rundown: http://forum.bodybuilding.com/showth...hp?t=121703981

[nobrah]

When on a cut people usually reccomend that you eat about 200-500 calories under your BMR.

I've never seen that recommendation. It's always in relation to your TDEE, which is BMR plus activity. Eating under your BMR is a bad idea in general because your body is getting insufficient nutrients for survival. It shouldn't be done for long, much less the usual length of a cut, which is on the order of months.