What is Basal Metabolic Rate (BMR) in Bodybuilding?
Basal Metabolic Rate (BMR) is the number of calories your body burns at rest to maintain basic life-sustaining functions such as breathing, circulation, and cell production. For bodybuilders and athletes, understanding BMR is crucial as it forms the foundation of your total daily energy expenditure (TDEE). Your TDEE is the total number of calories you burn in a day, and it includes your BMR plus the calories burned through physical activity, digestion, and other non-resting activities.
In bodybuilding, accurately calculating your BMR helps you tailor your caloric intake for either muscle gain (bulking) or fat loss (cutting). If your goal is to build muscle, you'll need to consume more calories than you burn (a caloric surplus). If your goal is to lose fat, you'll need to consume fewer calories than you burn (a caloric deficit). Your BMR is the baseline from which these adjustments are made.
Formulas for Calculating BMR
There are several popular formulas to estimate BMR. We'll use the Mifflin-St Jeor equation, which is widely considered one of the most accurate:
- For Men: BMR = (10 * weight in kg) + (6.25 * height in cm) – (5 * age in years) + 5
- For Women: BMR = (10 * weight in kg) + (6.25 * height in cm) – (5 * age in years) – 161
It's important to note that these are estimations. Factors like body composition (muscle mass burns more calories than fat mass), genetics, and hormonal status can influence your actual BMR.