How to determine your Resting Metabolic Rate
How to determine your Resting Metabolic Rate

This post will show you How to determine your Resting Metabolic Rate.

I have written before about Basal Metabolic Rate (BMR) or Resting Metabolic Rate (RMR) in my CITY Interval workout plan. What I didn’t really explain was how to determine what your RMR is.

How to determine your Resting Metabolic Rate

What is BMR again?

Before I show you how to calculate your RMR, first I will again point out what your resting metabolic rate is. Basal metabolic rate is the “official” name of your resting metabolic rate. BMR’s definition is “The amount of energy expended while at rest in a neutrally temperate environment in a post-absorptive state.”

What this means to a normal human is how many calories your ass burns up after you have fasted for 12 hours.

The “Post-Absorptive” state is the 12 hour part, since you eat every 2 to 3 hours (right?); and your body metabolizes different foods at a different rate, depending on what you’re doing. BMR is used as a standard of the amount of calories that you need in order to keep you healthy. For example, let’s say your BMR/RMR is 1800 calories. These 1800 calories are what you need for a proper functioning of all your vital organs such as your heart, liver, kidneys, skin, etc., etc.

How to calculate your BMR/RMR

Little girls first.

This is the formula women use to calculate their BMR/RMR

655 + (weight in kilograms x 9.6) + (height in centimeters x 1.8) – (age x 4.7)

So if you live in a country like America where we use pounds and inches to calculate weight and height instead of kilograms, here is a conversion method.

To convert kilograms to pounds.

1lb = .045kg or just divide your pounds by 2.2.

To convert inches to centimeters

1in = 2.54 or just multiply your inches by 2.5

A random example: Lets say you’re name is Ann and you are a 44 year old woman who weighs 138 pounds and is 5 foot 7 inches.

Weight: 138lbs / 2.2 = 62.72kg x 9.6 = 602.112

Height: 5’7″ = 67 inches – 67 x 2.5 = 167.5 or 168cm (I authorize this .5cm)

Age: 44 x 4.7 = 206

(655 + 602.112 + 168) – 206 = 1219 calories (BMR/RMR)

For my boys, here is your formula:

66 + (weight in kilograms x 13.7) + (height in centimeters x 5) – (age x 6.8)

A totally random example: You’re name is Lloyd and you’re a 34 year old male who is 6’2 and 185 pounds.

Weight: 185lbs / 2.2 = 84kg

Height: 6’2 = 74 inches – 74 x 2.5 = 185cm

Age: 34 x 6.8 = 231

(66 + 1151 + 925) – 231 = 1911 calories (BMR/RMR)

Even simpler method:

An even more simplified (crude) version of calculating your BMR/RMR is to take your current weight and multiply it by 10.

So the same woman a 138 pounds her BMR/RMR would be 1380 calories

The same man at 185 pounds his BMR/RMR would be 1850 calories

How to calculate the value of your daily activities.

Unless you’re just a total lazy ass, you don’t usually sit around all day doing jack. Even if you are a couch potato, you do spend time walking to the refrigerator or cabinets looking for a beer or a bag of Doritos.

If you don’t even do that, you need to get your fat ass up and start moving. If you don’t know what to do, just go outside and start walking. Yeah people will laugh, point and gawk, but whatever; you’ll live to tell about it.

Doing half ass cardio

As a rule of thumb, if you do some half ass cardio, by half-ass I mean moderate, meaning you’re not really going for it, but you struggle to have a conversation while doing it; you will burn about 2/3’s your bodyweight in calories every 10 minutes. So that means that if you half ass a treadmill workout and you weigh 185 pounds you burn about 123 calories every 10 minutes.

So what does half-assed on a treadmill mean? Well that depends on how good of shape you are in or not in. For me, I’m in decent cardiovascular shape so that would equate to about 7 miles per hour on a treadmill at a 2.5 incline. That’s an ultra half-assed workout; I could probably do that speed for an hour or more if I really wanted to.

How to determine your Resting Metabolic Rate

Calculating your caloric need

To guesstimate what you need to support your level of activity (or non-activity), use the criteria outlined below.

  • If you’re a couch potato and your idea of exercise is to have somebody give you a piggy-back ride to your minivan (cuz walking is way overrated), then drive to a local Krispy Kreme donut shop, you add 20% to your BMR/RMR
  • If you’re not a couch potato but not quite a gym rat; you sit in a cubicle everyday but workout 2 or 3 times per week, then add 40% to your BMR/RMR
  • If you’re a straight up gym rat (a person who loves to workout) and do it several time per week then add 60% to your BMR/RMR

Notes: 1 pound of fat is the equivalent to about 3,500 calorie. If your goal is to lose weight, start working out and use the guide I just outlined then cut about 500 calories from that total.

Ann as an example:

We will use Ann again as an example. Ann works in a cubicle but also works out 3 times per week. This would put her smack in the middle at +40% BMR. So her diet would include 1219 calories (using example #1) or 1380 (using example #2) + an additional 40%. If using example #1 that would be an additional 484 calories, or 552 additional calories if using example #2.

Warning: Don’t think that cutting more than 500 calories will give you better results; it won’t and will be a detriment to you losing weight.

Warning #2: Don’t go under 1300 calories per day, you need this much to keep yourself healthy.

This concludes my post on How to determine your Resting Metabolic Rate.


Charles Lloyd
Charles Lloyd

Self processed fitness missionary and author of most of the ridiculous fitness articles written on Charles Lloyd Fitness.com. I am not really a writer, but a workout fiend who happens to have a blog. The single mission of this website is very simple: Get You In Shape. I have been blessed with the gift of good health and want to share it with you. Join Me.

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