Why Your BMR is Important for Weight Loss

(Last Updated On: August 11, 2011)

istock_000011742077xsmallHi Everyone! As I mentioned in last week’s article, the formula for losing weight is simple, you just have to create a calorie deficit by burning more calories than you consume. Now this week I want to share with you some very important information on how to best determine your caloric needs. So if you’re really serious about weight loss you need to keep reading because there is a lot of very valuable and helpful information here.

The secret to weight loss is really understanding your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE). Because there is so much great information to cover here, I’ve decided to divide this article into two parts. This week (part A) I’m going to focus mainly on your BMR, while next week I’ll discuss and explain your TDEE (Part B).

Ok, so let’s look at your BMR. Simply put, this is the number of calories you’d burn if you stayed in bed all day. It does not include exercise, typing on the computer, yard work, walking, talking, sitting, driving your car, shopping or even thinking for that matter. Yet, your BMR is important because it accounts for 60% to 70% of calories you burn each day. Wow, can you believe that!!! Nearly two thirds of the calories you burn every day are the result of your BMR which includes calories burned for basic bodily functions such as breathing, blood circulation and maintenance of body temperature. So many people don’t realize this but it is truly a key factor in weight loss. Now I bet I have your interest!!!

So since exercising only accounts for 10 to 20% of the calories you burn each day you need to look at ways of also increasing your BMR if you are serious about weight loss. There are many factors that determine your BMR, including your age, sex, height, weight, thyroid, diet , lean body mass and genetics, but unfortunately you only have control over a few of these factors.

Take diet for instance. Diet is something you can control and just about everyone knows their diet is important for weight loss, but did you know that reducing your calorie intake too much can result in your BMR dropping as much as 20 to 30%? You need to create a calorie deficit if you want to lose weight, but you have to be careful that you don’t reduce your calorie intake too much or your BMR will decrease. It doesn’t make sense to go on an extreme calorie reduction diet that causes your BMR to also decrease. The smarter way to lose weight is to reduce your calorie intake more moderately and then to also increase your calories burned by exercising more. The American College of sports medicine (ACSM) says that the daily calorie level consumed for women should never drop below 1200 calories per day and 1800 calories per day for men. In, some cases this may still even be too much of a reduction and could cause your BMR to drop significantly. I’ll go more into this in next week’s “Part B” of this article concerning your TDEE.

Your lean body mass is also a BMR factor you can control, in fact, it’s probably the most important. The lower you body fat the higher your BMR. By the way, statistically men have lower body fat than women and typically have a higher BMR of about 10 to 15%. Ok, so a special note to all the women out there…we need to work a little harder at keeping our BMR’s from dropping. But nonetheless, both men and women need to work at keeping their BMR working optimally and the two biggest things you can do to increase your lean body mass is to eat healthier and lift weights. I know, you’re probably thinking “what about cardio activities? Don’t they assist in weight loss and lean muscle mass?” Well in the short run, the answer is yes, since cardio exercise burns many calories at the exact time you are doing the activity. However, in the long run, strength training is better for weight loss because it causes people to burn extra calories not only during their workouts but also in their day-to-day activities, which get this, even includes sleeping! However, before I continue on with my point of strength training being a greater benefit to weight loss through developing lean muscle mass, I do not want to discourage or discredit the importance of doing cardiovascular activities. Cardio activities promote cardiovascular health which leads to a reduced risk for heart attacks and strokes and promotes an overall better quality of life…so keep doing your cardio!

Now that I have made that point clear, let’s get back to discussing the most prominent factor that affects your BMR….lean body mass. Simply put, the more muscle you have the more calories you will burn. I know from posts I receive in my discussion forums that many women are afraid of lifting heavy weights out of fear of gaining weight. Unfortunately, this myth really does a lot of damage by persuading a lot women not to strength train. The reality is that the only way to gain weight is to consume more calories than you burn. Weightlifting burns calories and does not cause weight gain. If you gain weight during a strength training program it is not from the weightlifting, but instead comes from the excess calories you have consumed or temporary water weight gain. Without a positive caloric balance it is impossible to gain bodyweight. Let’s look at it this way, regardless, if you weight train or not, you will gain weight if you consume more calories than you burn each day. These extra calories will mainly be turned into body fat by the person who does not train with weights, while the same extra calories consumed by the person who trains with weights will be used to create new muscle tissue. You might be thinking that you would rather do cardio instead of lift weights to burn those extra calories. But remember, lifting weights develops lean muscle mass and since muscle takes up about one third the space of fat, you will not only look leaner, but will also increase your BMR. Since your BMR is responsible for most of the calories you burn each day you would be foolish not to take advantage of the best way to increase it. And guess what? Increasing your lean body mass increases your BMR and that translates to burning more calories all day long, even while you’re sleeping. Do I have you searching for your hand weights yet?

But wait, there’s even more! As you age, incorporating a thorough weight lifting program becomes even more important because your BMR will decrease about 2% every decade after the age of 20. This may not seem like a lot, but a 2% decrease for a person with a BMR of 1500 means they would burn 30 calories per day less than they did the decade before. This translates into a weight gain of nearly 3 pounds per year without taking into account any increase in calories consumed or decrease in their activities or exercise routine. This best way to counter the decrease in your BMR as you age is to increase your lean body mass and turn your body into a fat burning machine all day long!

Ok, I’m going to stop here and let all of that info digest. In next week’s “Part B” of this article I will tell about how to determine your maintenance level (TDEE ) which is the total calories you burn each day after including all of your calories burned from your activities and exercise program. In the meantime make sure to check out our Workout Manager which now will calculate your BMR and TDEE automatically for you. Just make sure to first click on the “Settings” icon and answer the questions will you see. Don’t forget to click on the “Save” button. Lastly, click on the “Weigh In” icon and enter your current weight. When you return to the Workout Manager home page you will see your BMR and TDEE.

See you next week!

Cathe Friedrich

14 thoughts on “Why Your BMR is Important for Weight Loss

  1. Ahh…well, I knew lifting weights was better, but I didn’t exactly know why. This was enlightening, Cathe, thanks. I still don’t like weights.

  2. Thanks Cathe! I love weightlifting better than cardio. I do your STS 3 days a week and cardio twice a week. The info given today was great. I understood it a little but not to this extent. Thanks for posting this. It makes more sense now.

  3. Hello Beautiful Cathe!! 🙂

    Wouldn’t expect anything less than superb from you – that includes your articles!

    I’m a former runner. Have been a runner most of my life. Of course that was my only cardio until I injured my right knee two years ago. Thanks to the injury every time I run I get re-injured. Apparently it’s chronic. At first I was disappointed but thankfully I bounce like a rubber ball and was back into the fitness groove in no time.

    Because I had lost two inches of muscle in the upper leg portion of my injured leg, weight training was a must. My butt muscles were also weakened as a result. Unfortunately because I suffered mild depression from not being able to get around and exercise (I normally live a very active life) I wasn’t able to motivate myself. Because I’m so picky (a former strength trainer myself) I didn’t want to turn to just anyone. Thankfully, I found you!

    Immediately I set about building my library and now own the complete STS, Core Max, Abs Circuits, Butts & Gutts (my fave!), Boot Camp & Muscle Endurance, Gym Style Chest & Triceps, and Gym Style Back, Shoulders, & Biceps.

    Being a previous strength builder and trainer myself, I already had most of the equipment and only needed the high stepper platform, which I purchased from you. Definitely worth the price! But then again, pretty much all of your stuff is!

    Anyway, to make a long story short, you whipped me back into shape in no time. At my best (8 reps, 3 sets) I was squatting 130 lbs, straight-leg dead lifts 65 lbs, chest press 100 lbs, one arm rows, 35 lbs, shoulder press 65 lbs, bicep curls 25 lbs, and two-hand tricep presses 40 lbs. I know I could have worked out with even more weight, but I didn’t have a spotter. I share this simply to drive home the point you made. Just because women work out with heavy weights does not mean they will gain weight or develop large muscles and look like a she-man.

    I’m only 5′ 3 1/2″ 115lbs. It takes a lot for me to gain muscle and lose fat. Cardio alone doesn’t do it. I get thin but lose the muscle mass. Strength training, however, does both.

    Recently I’ve taken up power walking while wearing a 15 lb weighted vest and 6 lb weighted gloves. I mix up my walks with squats, dead lifts, and walking lunges as well as a variety of upper body exercises. I’m hoping to eventually work up to the full 30 lbs of weighted vest and plan to continue my workouts even in spite of our brutal Canadian winters.

    By the way, did I mention I’m a 100% raw vegan, which is counterintuitive to what most people think about strength training people. And no, being raw vegan has nothing to do with why I have difficulty putting on muscle and losing excess fat. A slow metabolism has everything to do with that, which is another vital reason strength training is soooooo important!! In combination with a healthy diet, weight training really does help activate the thyroid and keeps it from becoming sluggish!

    An awesome article. Can hardly wait to read the follow-up Part 2.

    Thank you so much Cathe for being such a wealthy inspiration to so many women AND men (even my husband was working out with you via video. he thinks you rock!!)

    Much love and light,

  4. So, I understand exactly what you’re saying, but now I’m even more confused? My BMR calculates at 1597. I set my activity to moderate – I sit at a desk all day, but workout hard at least an hour a day. My TDEE comes out to 2475. I eat between 1600-1800 cals a day, closer to 2000 on Sat. My weight hasn’t moved in ages. Inches have dropped, but not pounds. I calorie counted EVERYTHING for about a yr, and lost 10lbs in the beginning, and now I’m stuck. I quit with the cal counting maybe a month ago, but am still aware of what I eat. So what’s the deal? I seem to be stuck, weight wise, no matter what I do.

  5. Hi Nan,

    There are only two possibilities in your case. Either you are consuming more calories than you think you are or your TDEE is lower than the formula indicates. Most people over estimate calories burned and underestimate calories eaten. Everyone who eats less calories than they consume will lose weight – there are no exceptions to this law of thermodynamics. Though you are probably just miscalculating your calories consumed and your calories burned, you could also have a thyroid issue. A problem thyroid can account for up to a 40% reduction in your BMR. In your case your BMR would be 638 calories lower than you think and your TDEE would only be 1475 calories per day. This would certainly explain why you’re not losing weight, but incorrectly estimating calories burned and your activity level would too.

  6. Thanks for the response. I actually just got thyroid results back today. It’s all good. I weighed and measured and recorded every bite for a year (isn’t that enough to drive a girl bonkers!) So the cal counts are accurate. I’ happy with the way I look and feel and what I can do physically, just the # on the scale bugs me. Gotta just learn to accept it. I also know I have a lot of extra skin (ew I know, but from a decent weight loss – so I think that may throw the numbers. It’s just THERE – can’t do anything about it, but it obviously has weight) The inches are coming down, so I’ll just keep going with what I know, and hopefully the scale will catch up. I will say calories burned during a workout are a guesstimate based on the workout manager and other databases I’ve looked at. I really have to look into an HRM. I was surprised to see the article on the FDA allowing for a 20% calorie variance. I caught a snippet of that on the news the other day when I was on my way out the door. Surprise!!! We aren’t eating what we think we are. Trying to stick to good, whole foods and lots of water. And keep on bouncing along. Obsessing over the number on the scale isn’t good, either. Thanks for the response.

  7. I also think my TDEE seems high. I am 5″3″ and 139 lbs and workout 5-6 days a week and have a sedentary job. It’s putting my TDEE at 2100+ calories/day. From what I know of my body, eating this much would cause me to gain weight in a skinny minute (pun intended!). I really have to get my calories below 1400 to lose weight historically. I know I don’t have a thyroid issue…it’s been checked. And I’m not technically overweight (though close to being), but it just seems high to me. Any other thoughts? I don’t think my calorie counts are 100% accurate, but also don’t think they’re off by THAT much.

  8. Nancy, the TDEE calculator gives and average number based on the information you input. The TDEE number that is calculated is not an exact number and may need to be adjusted by you as it can not consider genetic or thyroid factors. In school the class average may be an 80 on a test, but this doesn’t mean everyone who took the test scored an 80. Some of the class might have received a 100 and some might have failed the test with a score of less than 50. The same is true of the calculated value for TDEE. For most people it will be close to correct while others it may not be. In your case it does seem pretty close though since you have to eat less than 1400 calories to lose weight. That’s only a one pound weight loss per week based on your calculated TDEE. Usually a calorie deficit of 500 calories is a good safe number for a calorie reduction weight loss plan.

    Also, the following is a story I quite often tell that is related to your question. About 27 years ago a study was done at the University of Virginia concerning weight loss. Football players were put on calorie deficit weight loss program of 2000 calories per day. They were instructed to write everything down they ate each day no matter how insignificant it may have seemed to them. Scientist and doctors monitored the program. After a determined period of time all of the test subjects were weighed and the doctors and scientist were shocked to learn that hardly any of the players had lost weight as the science and math said they should have. They just could understand how players that were eating less calories than they were burning did not lose weight. It just didn’t make any sense. Then one of the doctors had an idea. They had all of the players turn in their journals and they removed any snacks and vending machines from the dorm. Then for the next several weeks each player was only given the exact amount of food they had listed in their daily journal each day and guess what? Every single player lost the weight as the math and formulas had predicted.

    The moral of this story is that people almost never calculate calories eaten correctly and always forget to list a few items that can add hundreds of calories to their daily intake. When combined with inaccurate food labels and overestimated calories burned this is why so many people can not lose weight. If you have calculated everything correctly and create a daily calorie deficit of 500 calories you will lose exactly one pound per week. This is not something that may happen, but instead is an absolute law of thermodynamics. If you don’t lose one pound per week on a 500 calorie deficit daily diet then you have either calculated calories eaten incorrectly or your TDEE is calculated incorrectly.

  9. Hi from Spain Cathe! Thanks so much for your article, can´t wait for part B next week! I kept a food diary as I was baffled as to why I wasn´t losing weight and yep, all those small things that you pop into your mouth (including drinks – coffee-fruit juice – alcohol etc) all add up! A biscuit here, a handful of crisps there, I realise that I have to be super strict! At the end of the day there are 3500 calories in a pound of fat so I know that I need a 500 calorie a day deficit. I sometimes eat 2 biscuits or a chocolate bar and actually FORGET that I ate it! So I have to ask myself ´why?´ why am I eating this? If the answer isn´t ´because I´m hungry´ I try hard to walk awy after all like they say ´a moment on the lips, a lifetime on the hips!´

  10. Thanks so much for your thoughtful reply.

    Your blog post inspired me to lift some weights this morning…it was Gym Style Legs for me. Great fun!

  11. If I’m reading the responses correctly, it almost seems impossible accurately calculate how many calories you’re buring through exercise. The calories burned indicator on my treadmill goes strictly by my speed, distance and time. My pedometer also incorporates my weight. Neither bring in my age as a factor. And then there’s the whole muscle ratio, which will increase your calories burned. But if you don’t really know what your muscle ratio is… that just adds more mystery.

    I do have an underactive thyroid; but have been taking medication for it for several years and it is “normal”, so long as I take the meds.

    Is there a way to really get an accurate indication of your calories burned? I’m using the Nutrition software on the Workout Manager and religiously mark what I eat and measure it before I put it on my plate. I don’t have snack food at my house, so I know I’m not munching on anything I don’t record.

    I like knowing about this BMR and TDEE, but I’d really like to have an accurate number.

  12. I think it is important for those who are making a switch from cardio and/or cardio and light weights to realize that it may take some time to raise the amount of total calories they burn at rest as a result of adding muscle. In other words, if one does one hour of cardio six times per week currently and burns, say 2,200 calories a week – when he or she switches to three one hour cardio and three one hour weight lifting sessions, the total number of calories burned for the week as the result of exercise may be more like 1,800. I think it takes time to increase one’s muscle mass up to the point where one’s resting metablic rate has increased enough to close that gap back up.

    It is worth the effort, though – I do believe weight training is the best bet for over-all health and long-term weight loss and maintenance. I just wanted to make some cardio junkies (like I was) aware that they may need to dial back their carb calories for a while when they start swapping weight training for cardio sessions.

  13. I can’t get the Workout Manager to figure my BMR and TDEE. I followed the steps –Settings, save, weigh in and the workout manager does not post the info…what am I doing wrong? Do I need to complete more info somewhere?

  14. Thanks for this article Cathe. For myself, I can see the difference since I’ve started with STS. I’m on my second round now and can’t stress enough how this has help, and continues to help me, as I turn 52 next month. Impatiently waiting for part II


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