BMR Calculator
Now that we defined BMR, let's see how we can use it to our advantage when it comes to losing weight.
Like figuring out your body fat, you can calculate your BMR in a variety of ways, use an online calculator to input your current weight, height and age or have it officially measured at a nutrition center. From what I've heard, the online calculator though it takes a generic approach, is fairly accurate, so that's what I used.
Plugging in my stats, I get the following figures:
My BMR is 1658
Now to determine my daily caloric needs I use the Harris Benedict Formula which multiplies my BMR by the appropriate activity factor:
- Sedentary (little or no exercise) = BMR x 1.2
- Lightly active (light exercise/sports 1-3 days/week) = BMR x 1.375
- Moderately active (moderate exercise/sports 3-5 days/week) = BMR x 1.55
- Very active (hard exercise/sports 6-7 days a week) = BMR x 1.725
- Extra active (very hard exercise/sports & physical job or 2x training) = BMR x 1.9
Now here is something else I recently learned, though I exercise quite a bit, if your job is one where you sit in a chair for about 8 hours a day and you drive 1-2 hours and when you get home spend most of the evening in bed, at computer desk or watching TV, you are considered sedentary. When I worked retail, I could call myself moderately active, as I spent 8 hours on my feet, walking up and down the store and hauling clothes and an hour a day walking to and from work.
An hour or so of exercise a few days a week does not make you an active person. But that's my theory. You can figure yourself accordingly if you feel active based on what you do.
Back to me ![]()
Sedentary (little or no exercise) = BMR x 1.2
1658 x 1.2 ='s a daily caloric needs of 1990 to maintain my current weight.
There are approximately 3500 calories in a pound of stored body fat. So, by creating a 3500-calorie deficit through diet, exercise or a combination of both, I'll lose one pound of body weight. (On average 75% of this is fat, 25% lean tissue) If I create a 7000 calorie deficit I will lose two pounds. The calorie deficit can be achieved either by calorie-restriction alone, or by a combination of fewer calories in (diet) and more calories out (exercise). This combination of diet and exercise is best for lasting weight loss. Sustained weight loss is difficult or impossible without increased regular exercise.
If I want to lose fat, a useful guideline is to lower my calorie intake by at least 500, but not more than 1000 below maintenance level. For people with only a small amount of weight to lose, 1000 calories will be too much of a deficit. Minimum calorie intake should never drop below 1200 calories per day for women or 1800 calories per day for men. Even these calorie levels are low.
Without factoring in exercise 1990 - 500 = 1490 daily calories to net me a 1lb loss. Here's where the numbers get tricky, say your daily caloric deficit fluctuates between 250-500, again not factoring in exercise, your deficit for 7 days will look like this:
M -200, T -175, W -500, Th -500, F -250, S -400 S -350
For a grand total of 2375 calories a .7lb loss (2375 / 3500), which may not even show up on the scale. Let's go a few more days into the following week shall we?
M -350, T -280, W -500
Well what do we have here? A 3505 deficit and your 1lb loss will show up, not on the 7th day, as is widely touted, but on the 9th day. Unless you are regimented and know your stats to a tee, I suspect most of us lose weight over a period of 7-11 days.
Back to me ![]()
Let's fast forward a few weeks, your resident fat fighter has shed 10lbs, hey it's not impossible, last time I blurted my stats on this site I was 196, today I'm 192 thankyouverymuch…waitaminute…::rubs eyes::…I. Lost. Weight. Boo-Yah!
At 186, my BMR is now 1615. Granted it's not a huge drop from 1658, but just enough to see at a lesser weight, I need less calories, 1938, to maintain my weight. If I continue to consume the same calories as I did before that netted my loss, 1490, I'll either stall or gain a bit.
To remedy that, I can do a few things, cut my calories down even more to 1438 (1615x1.2 = 1938-500 = 1438), but I'll eventually stall out at 1200, besides who really wants to eat less food? Or I can *gasp* work out, harder.
Say during 194-184lbs I walked on the treadmill at 3mph, from 184-174lbs I will need to mix it up, either start running at that same speed, or increase the incline to 1-2%. The time can stay the same, even the speed can stay the same, but the intensity must change.
Keep in mind, this is all very bare bones. I didn't talk about carb bloating, or dehydration or lifting weights or muscle mass or fluctuations or a host of other things that can make it frustrating.
If you just look at it in a 1 + 1 = 2 approach:
- Figure out your BMR
- Multiply it by your current activity level (be honest)
- Minus 250-500 calories
- Eat the reduced amount of calories and however long you guesstimate you've burned 3500, you'll net your 1lb loss. Speed things up by doing some physical activity, but try to keep it realistic by losing no more than 2lbs per weigh in.
- Every 10-15lbs, spot check your BMR again, especially if you feel a plateau kicking in, and revise your calories.
I know it's a lot of info to absorb, I tried to make it as simple as possible, but if you have any questions or even objections, definitely post them, it helps me see if my theories make sense.
Next entry: Mid Challenge Break
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7 Comments
Hi Renee...and fellow anti-challengers!
I calculated my BMR and then my caloric needs. The math geek inside of me...got all excited...and posted away at my site.
My BMR is 1666.2. My caloric needs are about 1999, not counting in exercise.
My usual calorie intake is about 1350.
So...on days in which I don't workout...I bank about 649 calories a day toward my goal. On days in which I do workout...and guesstimate about 350 calories burned (which on most days is more than that)...I bank about 999 calories a day.
So...losing one to two pounds a week is something that mathematically is right within my reach!
Arindana, I'm dangerous around numbers, they are just so sexy...rawr!
hee anti-challengers, you're too cute shelley ![]()
I'm totaling my deficit via how much I burn on the cardio machine, daily goal is 500+, not hard to do on the eliptical (sp?) you hipped me too.
Well I found the calculator and I wrote it down on paper. Here's what I came up with.
My BMR is 2178. I chose sedentary activity because I am on holidays right now and am not exercising enough and I'm not working.
Once I get back to work in September I'll choose light activity because I'll up the exercise and I teach all day. I do walk from class to class (7 classes) and I usually run all over the school at several points in the day and sometimes I sit and sometimes I don't so I'm not sure if I should choose moderate if I'm exercising 3-6 times a week. I'll get opinions later LOL
To maintain my weight I'll need to consume 2178 calories. After taking off 500 calories I'm left with 1678 calories.
It will be interesting to recalculate when I up the exercise and I'm back at work.
Of course if you are weight training you'll build the muscles and speed up your metabolism so who knows how that gets factored in. hehe
This thing is an awsome guide for people in my opinion. My BMR came out.
My BMR following the forumals comes out to 3752. (6'1, 365 Pounds, 21 years old). My current diet goes between 2100-2900 Calories. Even though this is more than 500 calorie deficit when you have this much fat I doubt you are worried about feeding it
. On top of the 2100-2900 though I am weightlifting and cycling/running so my daily calorie deficit is probally much higher. Hopefully in 2 months I will be able to look back and see that it all went well.
Already down 2 panth sizes and 3 belts. ![]()
Congratulations Tyler. I love hearing about the pants and belt sizes you've dropped. Even though I haven't added exercise to my weight loss efforts yet, your progress gives me hope.
This was a really cool exercise. My BMR is 2100.6 (220 lbs., 5'4", 33 years old, totally 100% sedentary). If I want to lose 2 lbs. a week I'd go down to 1600.6 calories. If I want to lose 1 lb./week I'd go down to 1850.6 calories. It's nice to know the calculations behind this because I have been using a food diary site that calculated this for me (myfooddiary.com), but I didn't know how they did it. It's nice to know I came up with the same numbers as the site.
That is such GREAT news Tyler!! I can't wait to hear from you in 2 months ![]()
Arindana, I forgot to add what Trixie said, you don't really have to do all this number crunching, the guide they usually tell people is: eat 1200-1500 calories to lose weight. By crunching the #'s you get a bit more accurate view for your own needs, plus you see how they came up with that caloric range.
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Wow. that's quite the number crunching!!