We were months into our deployment, and we all wanted to go home.
For several months, my crew and I (U.S. Coast Guard) had been floating out in the Caribbean sea, each of us doing our part for the mission.
As an Intelligence Analyst, it was my job to obtain any and all reports for the region in order to figure our the routes that the drug-laden cartel boats were using. Now, most of our patrols were very successful, with our ships interdicting thousands of pounds of cocaine.
However, for whatever reason, this mission had been abnormally dry. That is until one night, a few weeks before we were set to return to our homeport in Key West, we received an intelligence report from one of our intel centers that indicated a drug boat was en route miles off from our position.
Now, this was unusual, given that the center giving us the report didn’t normally send them to us. However, with no other leads, we mobilized and headed towards the position. Several hours later, as we approached its position about 10 nautical miles out, we launched our helicopter to obtain visual confirmation of our intel.
As they flew off to the last known position of the target, we awaited their acknowledgement over comms to go into official ready position. What followed next was disastrous.
The intelligence we were given had been faulty.
Instead of chasing a cartel boat full of drugs, we had inadvertently been tracking an allied naval warship for hours. My Commanding Officer was understandably angry and embarrassed. And although the intel report had not come from me, so was I.
It was an object lesson on how faulty intelligence, faulty metrics, and unknown information can have us spinning in circles. Which leads us into the next “secret” of fat loss: objective measurements via our BMR, or Basal Metabolic Rate.
So what is that? Why is it important?
Unlocking Your BMR: Defined
Basal Metabolic Rate (BMR) is the amount of energy your body needs to maintain basic physiological functions such as breathing, circulation, and cell production, even when you are at rest. Your BMR is the largest contributor to your total daily energy expenditure (TDEE) and can play a significant role in weight management.
Put another way, knowing your BMR is important because it helps you understand how many calories your body needs just to live. It provides a baseline calorie requirement, which can then be adjusted based on your physical activity level.
If you know your body needs 1500 calories a day just to live, breathe, and maintain all your bodily functions, you won’t be so inclined to fall for those 500 calorie fad diet scams. You’ll also have a baseline number to stay above when going into any cutting or dieting phase. Without accurate intel, you’ll do nothing but run in diet circles.
Unlocking Your BMR: The Formulas
Great, so you know BMR is important. The pros, athletes, and celebrities almost always hire people to figure out their BMR and numbers before putting them into a specific weight loss or muscle mass regimen. But how do we get our number? Enter the formulas.
There are several formulas used to calculate BMR (five of note), each with their own strengths and limitations. Here are five of the most commonly used ones:
- The Harris-Benedict Formula
- The Harris-Benedict Formula was developed in 1919 and is considered one of the oldest and most widely used BMR formulas.
- It takes into account gender, height, weight, and age to calculate BMR.
- The formula is as follows:
- For men: BMR = 66 + (13.7 x weight in kg) + (5 x height in cm) – (6.8 x age in years)
- For women: BMR = 655 + (9.6 x weight in kg) + (1.8 x height in cm) – (4.7 x age in years)
- The Mifflin-St Jeor Formula
- The Mifflin-St Jeor Formula is a newer formula developed in 1990 and is considered one of the most accurate BMR formulas.
- It is similar to the Harris-Benedict Formula, but with slight variations to the equations. The formula is as follows:
- For men: BMR = 10 x weight in kg + 6.25 x height in cm – 5 x age in years + 5
- For women: BMR = 10 x weight in kg + 6.25 x height in cm – 5 x age in years – 161
- The Katch-McArdle Formula
- The Katch-McArdle Formula is a more specific formula that takes into account the person’s body fat percentage.
- This formula is more accurate for athletes and bodybuilders who have a lower body fat percentage.
- The formula is as follows: BMR = 370 + (21.6 x lean body mass in kg)
- The Schofield Formula
- The Schofield Formula was developed in 1985 and is based on World Health Organization data.
- It takes into account gender, weight, height, and age to calculate BMR. The formula is as follows:
- For men: BMR = 22 x weight in kg + (height in cm x 0.7) + (age x 5) + 1,000
- For women: BMR = 22 x weight in kg + (height in cm x 0.7) + (age x 5) + 600
- The Cunningham Formula
- The formula was developed by Dr. Lawrence J. Cunningham in the 1980s and considered less accurate than other BMR formulas because it doesn’t take age, height, or gender into account. It is based on the assumption that the BMR of an individual is proportional to their total body mass and fat-free mass. The formula is given as follows: BMR = 500 + (22 x lean body mass in kilograms)
Unlocking Your BMR: So Which Is Best?
It is difficult to determine which BMR formula is the “best” as it depends on the individual’s unique circumstances and body composition.
Each formula has its own strengths and limitations and the accuracy of the estimated BMR can vary depending on the specific formula used.
For example, the Mifflin-St Jeor formula is considered to be one of the most accurate equations for estimating BMR, but it does not take into account an individual’s body fat percentage. The Katch-McArdle formula, on the other hand, takes into account body fat percentage, but is not as accurate for individuals with high body fat levels. The Schofield formula is based on a large database of measured BMR values, but may not be as accurate for individuals with unusual body compositions.
Ultimately, it is best to consult with your coach, or pick a standard formula with the greatest amount of accuracy (Mifflin-St Jeor). Additionally, it is good to use a combination of different formulas, or at least compare them together to spot the differences. The Ultimate Macro Tracker calculator has each of these formulas built in so you can compare and contrast.
Unlocking Your BMR: What’s next?
Once you have your BMR, the next step is to calculate your maintenance calories. Your maintenance calories are the number of calories you need to consume in a day to maintain your current weight. Why is that important? You want a foundational starting point before you cut calories or add calories to bulk. Once you have your maintenance calories, you can easily start cutting or bulking with a high degree of accuracy.
To determine your maintenance calories using your BMR, you need to take into account your physical activity level. Start with this:
- Calculate your BMR: See Above.
- Adjust for physical activity level: To account for the calories burned through physical activity, you need to multiply your BMR by an activity factor. For example, if you have a sedentary lifestyle, you would multiply your BMR by 1.2; if you have a light active lifestyle, you would multiply it by 1.375, and so on.
- Add the two numbers: The result is the number of calories you need to consume daily to maintain your current weight.
For example, if your BMR is 1500 calories and you have a moderate physical activity level, multiplying 1500 by 1.55 gives you a total of 2325 calories, which is your maintenance calorie intake.
Again, this is important: your maintenance calorie intake is a starting point for developing a balanced diet plan.
If you consume more calories than your maintenance level, you’ll gain weight. If you consume fewer calories, you’ll lose weight. Once you understand this, you can break up your maintenance calories into specific macro ratios (proteins, carbs, fats) and then start cutting (start with 100-200 calories from your maintenance number and go from there).
If you need help with this, my Ultimate Macro Tracker is a month away from release. Keep your eyes peeled!