I read a lot of blog posts and forum messages from people who feel confused and dismayed about plateaus and slow weight loss. Knowing your personal total calorie burn is important so you can figure out how much to eat - so you can set up an appropriate calorie deficit for losing, or set a target to maintain.
There are tools available here at SP for estimating your basal metabolic rate and calorie burn through exercise, etc. Unfortunately they can be wildly inaccurate because they are based on formulas for average humans and not based on YOU, individually.
If you like podcasts, there's a really good one by Leigh Peele about how estimating metabolism is almost more of an art than a science:
This topic comes up with such regularity that I've decided to write a blog post about it, so I can just refer people here when I see it again.
Here is how you calculate your own, individual daily calorie burn rate:
You take the calories eaten and compare it to what your weight is doing on the scale.
Suppose you are eating on average 1600 calories per day and losing about 1.6 pounds per week.
1.6 pounds is roughly equivalent to 3500 calories times 1.6 = 5600 calories. So if you're losing about 5600 calories per week, divide that by seven to figure out your daily average deficit. In this case that is about 800 calories.
So if you're taking in about 1600 calories per day and are 800 calories below your daily needs, that means your daily calorie needs are about 1600+800 = 2400 calories.
Suppose you're eating about 2000 calories per day and gaining about 0.5 pounds per week?
0.5 pounds times 3500 calories is about 1750 extra calories per week. Divide that by seven and it is about 250 calories extra per day.
Those numbers would mean that your total burn is about 2000 - 250 = 1750 calories per day.
Suppose you are eating about 2100 calories per day and have been at a plateau for about 2 weeks. That makes the math really easy. It means you're burning roughly what you're eating, 2100 calories.
This principle is laid out in beautiful detail in the Hacker's Diet online
We also have a Spark Team about this:
There are a few requirements to make this work. And you need to apply them consistently over weeks in order to figure out what is going on with your body.
1) You need to have a fairly consistent exercise routine. If you collect the numbers while training for a triathlon and then try to apply them during a 2 week cruise in the tropics, your estimates will be off.
2) You need to track your food. ALL of your food. And you need to track it accurately. If you don't know how much you are eating, you can't figure out how much you are burning. Because I love accuracy so much, I weigh everything I eat; using cups and teaspoons isn't as precise.
Here is a blog post about using a scale to track your food:
3) You need an accurate estimate of your weight. Daily fluctuations due to hydration can be as much as 2%. Weighing yourself once a week will help you see a downward or upward trend, but it won't take out the +/- 2% error problem for each measurement.
Because of this I like to use a weighted moving average of my daily weight. There are a number of free sites that can calculate this for you.
I personally like physicsdiet.com
but the site appears to be down at the moment.
There are links to iphone and Android apps that do this in the links at the Hacker's Diet spark team:
Or you can use the principles of the Hacker's Diet and make your own spreadsheet as I have done over at Google Docs: docs.google.com/spreadsh
However you do the tracking of your weight and food, you need to do it accurately and consistently. The better your data, the more clearly you will be able to understand the results.
So, after a week or so, figure out your average calories eaten and how much you're burning or storing based on your weight. With those numbers you can calculate an appropriate deficit. Most sources recommend a deficit of about 500 calories per day to lose about a pound a week.
We can safely lose about 1% - 1.5% of our weight per week. yourlife.usatoday
During the year that I lost 160 lbs I ran a deficit of more than 1000 calories per day without much problem.
Now that I'm back in maintenance range it's even more important to have accurate estimates for my calorie needs - I have to know how much to eat!
That first example above is actually me. I've been eating about 1600 calories per day and losing about 1.6 lbs per week. My plan is to raise my eating target by 100 calories each week. So next Monday I'll target 1700 calories per day and see what happens. The week after that I'll target 1800 calories per day.
Since I started about 800 calories below my needs it should take about two months to stabilize, assuming my activity levels remain about the same. I estimate that I'll lose about 7 more pounds during those two months, and it should taper off to almost no weight change from week to week.
If I get sidelined by injury or illness my burn rate will drop. If I end up being more active than this my burn rate will go up. So I'll be watching the numbers carefully.
Here is a graph of my estimated calorie intake and burn. You can see that it varies somewhat depending on my activity.
Just for reference, this is a typical week's exercise for me:
M - Tae Kardio at lunchtime, Body Pump Class in the evening
Tu - Spinning in the evening
W - Tae Kardio at lunchtime, Body Pump Class in the evening
Th - Tae Kardio at lunchtime, Spinning in the evening
F- Rest, stretching, sometimes a deep tissue massage
Sa - Playing outside (kayaking, XC skiing, snowboarding, road cycling, etc.)
Su - Playing outside (usually kayaking or road cycling)
*I wear 5 lbs on each ankle & wrist for Tae Kardio. I take the seat off the spin bike and do the whole class standing and hovering. I lift as heavy as I can in Body Pump without losing form.
Having said all this, I need to add a disclaimer that this whole endeavor is not really about the number on the scale at all. The number on the scale is just a convenient, rough indicator. What I really care about is body composition and athletic performance.
How you control that is with WHAT you eat, and HOW you burn your calories. And tracking it is a much more difficult can of worms.
Here's a blog post about tracking body composition: