You’ve heard all the cliche’s, right? “Abs are made in the kitchen”, “Weight loss is 20% training, 80% nutrition” and the classic, “You are what you eat”. Here’s the thing about cliche’s…a lot fo them exist because they are true. At the end of the day, it all comes down to calories.
I think all of you understand that over eating will lead to weight gain. What I get asked a lot, though, is, “How do I know how much is too much?”. That’s what we’re going to talk about today:
- Basal Metabolic Rate: What is it and How to Calculate It
- Activity Multiplier Chart/ TDEE Equation
- Calculating Your Caloric Deficit
- How to Keep Track of Your Food Intake
THE ENERGY RULE: CALORIES IN VS. CALORIES OUT
The energy rule is the most important concept to understand when it comes to weight loss. We measure energy in calories. Calories going into your body cannot exceed the amount your body uses to function on an average daily basis.Calories going into your body cannot exceed the calories your body uses to function on an average daily basis. Click To Tweet
In other words, CALORIES ARE KING. If you eat more calories than you burn, your body turns excess calories into fat. Consume fewer calories than your body requires and your body will use stored fat as energy instead. Pretty simple, right?
In theory, it is simple. The confusion comes when you want to know how much energy you consume vs. how much energy you burn. The biggest problem here, in my experience, is that most people think they consume less than they actually do. Even worse, they also think they are more active than they actually are.
First off, if you want to make all of this really simple, I suggest getting a wearable device. Something like a FitBit that will give you a baseline of how many calories that you burn on average. If you don’t want to throw down money for that, or if you just want a better understanding of what it all means, read on.
Your Total Daily Energy Expenditure is how many calories that you burn on a average daily basis.
CALCULATING YOUR BMR
Calculating your BMR (Basal Metabolic Rate) is step one. This is how many calories your body requires to power all internal systems with no activity accounted for.
MEN: BMR = (10 x Weight in Kg) + (6.25 x Height in cm) – (5 x age in years) + 5
WOMEN: BMR = (10 x Weight in Kg) + (6.25 x Height in cm) – (5 x age in years) – 161
Knowing this comes in handy on days when you have very little activity. Sick days, long car rides, or just lazy days mean you’re burning probably just over your BMR.
CALCULATING YOUR TDEE
Now that we know how many calories your body needs to function without activity, we can consider the activity. There are two factors to consider:
- Normal daily activity (Non-Exercise Energy Thermogenesis or NEAT)
- Exercise-based activity
Using the activity multiplier chart below, you can account for the movement you get throughout the day. This is the part that sometimes trips people up. For example, I walk about 10,000 steps a day and weight train 5x a week, but am sedentary outside of that. I personally select the “Light Exercise” multiplier because my training isn’t high calorie burning.
Remember when you were sitting in high school algebra trying to figure out when the heck you were going to actually use algebra? Well here we are!
If you can tear yourself away from all the traumatic high school memories, I will give you an example to bring it all together
- Age/Sex: 35, Female
- Height: 5′ 4″
- Weight: 150 pounds
- Job: Desk Job, 8am-5pm
- Exercise: Nightly walks + Spin Class 1x week
(10 x 68.18) + (6.25 x 162.45) – (5 x 35) – 161 >>
(681.8) + (1,015.3125) – (175) – 161 = 1,361 CALORIES = BMR
1,361 x 1.375 = 1,871 CALORIES = TDEE
HOW TO CALCULATE CALORIC DEFICIT TO LOSE WEIGHT
You have now calculated how many calories you are expending. Now we turn to the other half of the Energy Rule. How do you figure out what you need to eat to lose weight? A really manageable deficit is from 10-15% of your TDEE.
To use our above example, Jane would be shooting for 1,590 – 1,688 calories per day.
A more aggressive approach would be 15-20%. So Jane would bottom out at 1,496 calories. I don’t recommend going over 20%, as it is typically not sustainable.
Your body will begin to adapt to your prescribed deficit, so it is wise to start at 10% and give yourself room to drop as your body responds.
You can, however add more activity to get a larger deficit. However, practice extreme caution here, as burnout is likely if you go too crazy.
HOW TO TRACK CALORIC INTAKE
I highly suggest getting a calorie counting app such as MyFitnessPal (what I use), My Macros+ or many others. These apps will help you figure out what you are eating and figure out where you can make adjustments to suit your goals.
In fact, simply tracking calories is one way to get a truly accurate account for maintenance calories (TDEE). This route require less math and more patience (3-4 weeks of honest tracking). Track what you normally eat and your corresponding weight and figure out the caloric intake that keeps your weight consistent.
QUICK TIP: People often skip condiments and cooking oils when tracking. These calories add up quickly and can deter your goals if overlooked.
We’ve gone over a lot here: BMR equations, TDEE equations, caloric deficit equations and how to track what you eat. I hope that I left you with some confidence of where to start your weight loss journey and how to be successful. Feel free to comment with any additional questions you have about any of these equations or concepts below. And if you have friends or family struggling with the same issues, share the post or images and tag me in the posts!