Step 1 – Figuring Out Calorie Needs. Luke’s first step was to figure out how many calories his body burned each day. To figure this out, we used two equations. The first one, The Harris-Benedict Equation, is the most popular and easiest to use. It takes into account weight, height, gender, age and physical activity level. Unfortunately, since it doesn’t measure body composition, it isn’t the most accurate. The next equation we used was The Katch-McArdle. This equation only takes into account lean body mass (total body weight minus total fat weight).
- Harris-Bennedict: BMR = 66 + (6.23 x weight lbs) + (12.7 x height inches) – (6.76 x age)
- Luke’s BMR = 66 + (6.23 x 220) + (12.7 x 73) – (6.76 – 22) = 2215
- Katch-McArdle: BMR = 370 + (21.6 x lean body mass lbs / 2.2)
- Luke’s lean body mass = 220 x .17 (his body fat percentage) = 37 pounds of fat. 220 – 37 = 183 lean body mass
- Luke’s BMR = 370 + (21.6 x 183 / 2.2) = 2166
- Calorie Calculator
Both of these equations estimate basal metabolic rate (BMR) which is only the calories your body needs each day to stay alive. They don’t factor in physical activity. To do that, we used the physical activity multiplier.
- Little to no exercise: BMR x 1.2
- Light Exercise (1-3 days per week): BMR x 1.375
- Moderate exercise (3–5 days per week): BMR x 1.55
- Heavy exercise (6–7 days per week): BMR x 1.75
- Very heavy exercise (2x per day, very intense workouts): BMR x 1.9
The multiplier works by matching your activity level with the corresponding number. The best description that matched Luke’s activity level was heavy exercise, 6-7 days per week (1.75).
- Harris-Bennedict BMR: 2215 calories x 1.75 = 3876 calories per day
- Katch-McArdle BMR: =2216 x 1.75 = 3790 calories per day
Since both equations gave us similar results, we went with 3,800 calories per day. That’s the amount of energy that his body needed to maintain his weight of 220 pounds. If he didn’t want to lose any weight, he would have needed to eat 3,800 calories per day.
To begin Luke’s weight loss, our first order of business was to put him into a calorie deficient state. Since we knew his body burned 3,800 calories per day, weight loss would require him to eat less than that to be successful.
One pound of body fat contains about 3,500 calories. To lose one pound, you need to create a calorie deficit of 3,500 calories. Since it’s not possible to have that sort of calorie deficit in one day or even a few days,spread the calorie deficit over the span of a week. To lose one pound in a week, you need to create a calorie deficit of 3,500 calories per week or 500 calories per day (3,500 calories / 7 days per week = 500 calories per day). To lose 2 pounds per week, double the deficit to 1,000 calories per day.
Luke started off eating 3,200 calories per day. Cutting 1,000 calories per day out of a diet could lead to a slow down in metabolism which would impede weight loss. The body’s metabolic rate isn’t set in stone. It’s fluid and can adjust to changes in calorie intake. If you cut your calories drastically, your body will react with a slowdown in it’s metabolic rate to preserve energy. This 600 calorie per day deficit would lead to weight loss of about 1 pound per week.
Step 2 – Counting Calories. When I first suggested to Luke that he count his calories, he probably thought I was crazy. But after explaining that counting calories was one of the only ways to guarantee your success, he quickly incorporated it into his routine. The problem that counting calories solves is that we tend to underestimate how much we eat. Underestimation of calorie intake leads to eating more calories than you’re supposed to which can turn into unwanted weight gain.
Luke chose to count calories by writing down everything he ate in a small notebook. He carried the notebook around with him to allow for the annotation of any snacks and unplanned meals he had throughout the day. Accounting for all the calories he ate was important because a shift in a few hundred calories could have sent his weight loss plan off, especially if that shift happened everyday. In Iraq, every food item had a nutrition label that listed calorie content. This made counting calories fairly easy. In the real world, a small calorie “dictionary” such as Calorie King or a smart phone app would make tracking your intake easier.
To ensure that he didn’t go over his daily calorie allotment, we planned out his intake for each meal rather than just state a daily goal. We started by subtracting the calories his mandatory daily protein shakes (see supplements below) from his total calorie intake. His post workout protein shake contained 650 calories and his nighttime protein shake contained 250 calories.
- Calories from food = 3,200 – 650 (post workout protein shake) – 250 (nighttime protein shake) = 2,300 for food and snacks
Since breakfast was served too early, Luke survived off of protein shakes, snacks and two meals: lunch and dinner. We gave each meal 1,000 calories which allowed for 300 calories of snacks throughout the day. Not only did he know how many calories he needed each day, he knew how many calories he could eat at each meal and how many he had left over for snacks. This ensured that he would neither go over his allotment or come up short at the end of the day. Here is another breakdown of what his day looked like:
- post workout protein shake (breakfast): 650 calories
- lunch: 1,000 calories
- snacks: 300 calories
- dinner: 1,000 calories
- nighttime protein shake: 250 calories
- total: 3,200 calories
Table of Contents
Part 1: Calories