Calculations for getting this number vary wildly depending upon the person. For example, a 30 year-old, 6 foot man who weighs 180 pound is going to burn in the neighborhood of 1900 calories a day no matter what. A 30 year-old, 5-foot-6 woman who weighs 130 pounds is going to burn an average 1400 calories a day, give or take. How is this number determined, you ask? There are a number of different equations to calculate BMR, but I generally use the Harris Benedict Equation. This is how the Harris Benedict Equation works:
- Women: BMR= 655 + (4.35 x weight in pounds) + (4.7 x height in inches) - (4.7 x age in years)
- Men: BMR= 66 + (6.23 x weight in pounds) + (12.7 x height in inches) - (6.8 x age in years)
I'm aware that's an awful lot of math, but you can always go HERE and get the number for yourself without having to break out the calculator.
Is this number 100% accurate? Yes and no. The only thing this formula really doesn't take into account is lean body mass (muscle) vs. total body mass (fat and muscle). That's why it's always best to be honest when assessing your activity level when using the calculator I gave you the link to. If you don't exercise at all, your calorie intake should only be your BMR x 1.2. If you are in the weight room or on the field 6 or 7 days a week, you could be looking at a calorie range of BMR x 1.9.
The number you're given in the calculator is assuming you're only interested in maintaining your current weight. If you want to lose weight, I would recommend subtracting no more than 700 calories from this number. If you want to gain muscle mass, add 700. Any more than that, especially when losing weight, you run the risk of losing muscle and damaging your metabolism. If you're trying to gain muscle, too large of a surplus and you could easily gain as much fat as you do muscle.
Got it? I hope so. If not, contact me HERE and I'll be happy to answer any further questions! I'll be back tomorrow with another post. Until then, here's some Motivation Monday stuff for you!