Today is the first day of the Summer Shred Dietbet. So I thought I'd start at the most logical place for people beginning any health journey.
Many of us have grown up with the simple understanding that "less calories in, more calories out" (or a caloric deficit) is the key to weightloss. And in the most simplistic terms, sure that's correct. “One pound of fat is around 3,500 calories, and safe fat loss is one to two pounds per week.” To lose one pound of fat per week, you'd need a 500-calorie deficit each day. True. But we are missing a key element. We are drilling this mantra into our own heads, our children's heads, the next generation's heads without presenting this basic piece of information.
YOUR BODY IS A MACHINE
Small words now. It needs fuel (food and nutrients). If you don't give it enough fuel, it can't work properly. So basically, the trick is determining how much fuel your premium, luxury, fine as heck automobile of a self needs to run properly!
First, let's talk about these pesky little calories. Calories aren't little fat bubbles that add up in your body. Calories refer to a unit of energy - how much "energy" your body can receive what you're taking into your body. Calories aren't bad for you. Your body needs calories for energy. (But eating too many calories — and not burning enough of them off through activity — can lead to weight gain. That's where we get our pesky little mantra about calories being bad)
So how do we determine "how much fuel" our bodies need so that our machine can run without having to keep a few spare fuel cans in our trunk (or on our love handles)?
OKAY - If you tuned out above, here's where you tune back in!
Calculating our BMR
First - we calculate our estimated BMR (Basal Metabolic Rate) or how many calories our bodies would need to run in the most relaxed sedentary mode, sleep - like temporary low power mode on your phone. This is crucial because the body burns energy ALL DAY LONG, even if you aren't doing anything. So if we are eating less than that required number, our body isn't getting enough fuel to simply exist and your machine isn't functioning properly (plus you're probably storing unnecessary fat).
So how do we do this? There are lots of different formulas but you're going to get roughly the same results.
You need your height, weight, age (BMR tends to decrease with age), and gender.
You can calculate for yourself using this formula:
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)
Or this one:
For women: BMR = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (years) – 161
For men: BMR = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (years) + 5
Or you can use a simple online calculator like this one or this one
Calculating Our TDEE
Second: Okay - so we know our BMR, or how many calories our body burns if we just rest. Now we need to know how many calories our bodies NEED! (STAY WITH ME!) We need to factor in our activity level so that we know how much energy our body is using when we are active - whether that's simply standing up to walk from our desk to the water fountain or climbing a mountain. We do this by finding our Total Daily Energy Expenditure (TDEE). TDEE is the most important bit of information available to us when trying to gain muscle or burn fat and lose weight, because it is the total number of calories we burn - so it includes sleeping, eating, moving, exercising, anything you do in your daily life. With our TDEE, we can estimate many calories to consume to burn body fat or gain (preserve) muscle.
BMR x activity factor
Amount of Exercise/Activity
|
Description
|
TDEE/ Maintenance
|
Sedentary
|
Little or no Exercise/ desk job
|
TDEE = 1.2 x BMR
|
Lightly active
|
Light exercise/ sports 1 – 3 days/ week
|
TDEE = 1.375 x BMR
|
Moderately active
|
Moderate Exercise, sports 3 – 5 days/ week
|
TDEE = 1.55 x BMR
|
Very active
|
Heavy Exercise/ sports 6 – 7 days/ week
|
TDEE = 1.725 x BMR
|
Extremely active
|
Very heavy exercise/ physical job/ training 2 x/ day
|
TDEE = 1.9 x BMR
|
Or you can use a simple online calculator like this one or this one.
OKAY- HAVE YOU GOT IT!?!?! This total right here, your TDEE, is how much fuel (or how many calories) your body needs to run at this age, weight, height, and activity level without losing or gaining weight.
In my next post, I'll talk about how to take your TDEE and adjust your caloric intake depending on your goals.