Updated: Apr 18, 2019
While online macro calculators may be a great starting point for the individual who is new to tracking food, they may not be the best option, especially for experienced athletes. These calculators take factors like age, height, sex, lean body mass, body fat and activity level to predict your energy needs. This data provides a great starting point to calculate your basal metabolic rate (BMR), which is an estimate of the rate at which your body uses energy for vital functions such as breathing. Yes, your body REQUIRES a certain threshold of calories each day even if you lie in bed all day! Eating below this minimum daily requirement consistently can lead to chronically elevated cortisol levels (stress hormone) which create a multitude of issues! This minimum caloric need is then multiplied by another number based on your activity level to determine your total daily energy expenditure (TDEE), which is an estimate of the total calories you burn each day. These calculators do NOT take into account factors like your current health status, current diet composition, dieting history, training intensity to an extent, recovery needs for performance athletes, medications affecting your diet & metabolism, and genetics amongst other variables. Example: Me 28yrs old 5’6” 110lbs Activity level: low during post surgery recovery
Macro calculators estimate I should be eating between 1300-1400 kcal/day to MAINTAIN current body weight. I’ve been eating 2200-2400 kcal/day (actually higher than pre-surgery intake now bc low carb) and my body weight has not fluctuated above 110lbs.
Why? The macro calculators do NOT take into account that I have spent YEARS building up my caloric intake to support the amount of muscle mass that I’ve added onto my small frame (see post on nutritional periodization for more info on this). If I ate within the recommendation range of 1000 kcal UNDER what I’m currently consuming, I would have lost all my muscle mass within a few weeks. Instead, I have managed to hold onto most of my muscle mass with minimal activity output because I took MORE variables into account to program my unique maintenance caloric needs!