Hey, there. I recently had a rather…ummmm…frustrating revelation. I stopped losing weight, and for a gal who gained 50+ pounds per baby, well, that’s not good. So I did some soul searching and discovered that even though I’m breastfeeding, I’m eating way more calories than my body needs.
How did this happen?
Why I’m so glad you asked! I was relying on my BMR that I’d calculated over 5 years ago. OOPS. Time to go back to the drawing board! Since I’m taking a second look at this, I wanted to be sure to share this with y’all, too.
What Is Basal Metabolic Rate?
Your Basal Metabolic Rate (BMR) is the amount of calories that your body needs to lay in bed all day and do nothing (wouldn’t that be nice!). This is the amount of calories that you MUST EAT in order to maintain your body’s mass at rest. BMR does NOT include your daily activities.
To Determine Your BMR, Use This Equation
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 )
But Wait! There’s More!
After you know your BMR, you need to find out what your Total Daily Energy Expenditure (TDEE) is. This is calculated by multiplying your BMR by your Activity Metabolic Factor (AMR).
Your AMR is determined by your activity level during an average day. In general, most people will find that their AMR to be 1.2 (sedentary). It is important to remember that AMR does NOT include your calories burned through exercise.
Exercise increases your overall energy expenditure and should be added to your TDEE. For example, I work from home and chase two boys, so I would be considered “lightly active”, but when I exercise, I can add the number of calories I burn during my workouts to my TDEE. This increases my daily calorie expenditure. I find it easiest to view exercise as an “out of the ordinary” activity. Let’s make it simple:
BMR x AMR + calories burned through exercise – calories consumed = DAILY DEFICIT (DD)
Do You Have A Heart Rate Monitor?
If not, you should. Personally, I think that it is important that I make mention of the fact that I use a Polar FT4 Heart Rate Monitor to determine the exact amount of calories that I burn through exercise. Whenever I workout, I wear it. This way, I get an accurate picture of my daily expenditure.
If you DO NOT have a HRM, well…think about getting one.
In the meantime, here’s a breakdown of the different “types” AMR:
- Sedentary = BMR X 1.2 (little or no exercise, desk job)
- Lightly active = BMR X 1.375 (light exercise, approx. 1-3 days/wk)
- Mod. active = BMR X 1.55 (moderate exercise, approx. 3-5 days/wk)
- Very active = BMR X 1.725 (hard exercise, approx. 6-7 days/wk)
- Extra active = BMR X 1.9 (hard exercise 7 days a week, physical job, training more than 1x/day)
If your AMR is anything BESIDES 1.2, here is the calculation that you will need to use:
BMR X AMR – calories consumed = DD
Creating a calorie deficit is actually fairly simple. In order to lose weight, you HAVE TO consume less than you burn. It all comes down to CALORIES OUT – CALORIES IN. In order to lose, you have to know what your deficit is every day (even your rest days), and you can accomplish this through journaling. In order to lose a pound a week, you need to burn 3,500 (1 pound = 3500 calories) calories in that week. This breaks down to approximately 500 calories per day. This can be accomplished one of three ways:
- 1. Create a 500 calorie deficit from your diet every day
- 2. Create a 250 calorie deficit from your diet and burn 250 through exercise per day
- 3. Burn 500 calories per day through exercise alone
I am blogging about this because it is SO VERY IMPORTANT to understand that you MUST EAT in order to lose. If you do not consume enough calories, your body will go into a “starvation mode” where you will be losing muscle, not fat.
If you continue to consume below your BMR for too long, then your body will eventually stop losing altogether. This severely inhibits your metabolism and could potentially cause long term damage. I want everyone to understand that food is FUEL that your body needs, ESPECIALLY if you are working out.