BMR (men and women) = 370 + (21.6 X lean mass in kg)
Example:
You are male
You weigh 172 lbs (78 kilos)
Your body fat percentage is 14% (24.1 lbs fat, 147.9 lbs
lean)
Your lean mass is 147.9 lbs (67.2 kilos)
Your BMR = 370 + (21.6 X 67.2) = 1821 calories
Now that you know your BMR, you can calculate TDEE by multiplying your BMR by the following activity factor.
Activity factor
Sedentary =BMR X 1.2
Lightly active = BMR X 1.375
Moderately active = BMR X 1.55
Very active = BMR X 1. 725
Extremely active =BMR X 1.9
Continuing with the previous example:
You are a 172 lb. male with 14% body fat and a BMR of 1821
Your activity level is moderately active (work out 3-4 times
per week)
Your activity factor is 1.55
Your TDEE = 1.55 X 1821 = 2822 calories
Once you've determined your TDEE, the second step is to increase your calories high enough above your TDEE that you can gain weight. It is a basic law of energy balance that you must be on a positive calorie balance diet to gain muscular bodyweight. If you consume the exact amount of your TDEE you will simply maintain your weight. Generally speaking, you'll need to add another 300-500 calories per day onto your TDEE in order to gain weight. To be more specific, add a minimum of two calories per pound of bodyweight on top of your TDEE to determine your optimal caloric intake to gain weight.
Continuing with our example:
Your weight is 172 lbs.
Your TDEE is 2822 calories
Your additional calorie requirement for weight gain is 2
X 172 = 344
Your optimal caloric intake for weight gain is 2822 + 344
= 3166
Using the formulas above, we have determined that our "typical"
172 lb. moderately active male will need 3166 calories to
gain weight. Keep in mind that this is merely an estimate:
All calorie expenditure formulas are estimations. Due to
genetic factors, there may be a 20% variance of BMR either
way. Age is another factor that you may want to take into
consideration.
According to Dr. William Evans, PhD., one of the world's leading authorities on exercise and aging, we may need as much as 100 calories less per day per decade to maintain our body weight. Also consider that certain athletes train so frequently and so intensely that their TDEE can be off the normal activity scale limit of 1.9. Daily energy expenditure can be much higher for competitive athletes or extremely active individuals. Some triathletes and marathon runners have been reported to require as many as 5000-6000 calories per day or more just to maintain their weight!
Don't just focus on gaining weight. It doesn't do you any good to gain weight if most of it is fat. The goal of a weight gain program is to gain lean muscle mass with little or no increase in body fat. If you have access to body fat testing, get it done every 1 -2 weeks. If you find yourself gaining fat, first add in 20-30 minutes of cardio 3-4 days per week. If, after adding cardio you still gain fat and the quality and quantity of calories is correct, then you will need to begin cycling your calories up and down in a "zig-zag" fashion. Three high calorie days at your optimum calorie intake for weight gain, followed by three lower calorie days at or slightly below your maintenance level (TDEE) will allow you to add solid weight while keeping your body fat in check.
Using these calorie guidelines, you can expect to gain muscular bodyweight at a rate of 1/2 to 1 lb. per week, or slightly slower if you are female. If two weeks go by and you haven't gained any weight, you're doing something wrong; most likely, you're not eating enough and you should increase your calories. After 3 - 4 months, the rate of muscle gain tends to slow down closer to 1/2 pound per week. Eventually, as you get closer and closer to your genetic limit for carrying muscle mass, the rate of muscle gain will slow down to 1/4 lb per week. Even at this rate, that's still 13 pounds of solid muscle per year.
In Part Two of "How to Gain Lean Bodyweight" will discuss meal frequency, meal ratios, caloric density and proper food choices for packing on the muscle.
>> Click here for Tom Venuto's Burn the Fat Feed the Muscle program
