Posts Tagged ‘calories’

Basal Metabolic Rate and METS – Biggest Loser Theory

September 18, 2008

I wanted to know how many calories I needed to eat to find my food deficit per day when I count calories as I eat. I also wanted to know how many calories I burn doing exercise so I can add that to my food deficit. I can then take these two numbers combined and count them against how much weight I need to lose, presumably all fat, times 4000 calories per pound of fat. This is where I came up with about a quarter million calories for my around 60 pounds I am in the process of losing. Here is what I found. (skip to the bottom if you want the short step by step version)

In order to know how many calories you burn during an exercise you need to know two things. First how hard you are working out in units called METS, and second your Basal Metabolic Rate (BMR) which is your personal multiplier. It is possible to determine it without these two numbers specifically, for example you might know how many watts you are producing and can therefore get to the same point. But, the formulas all have the components and could be separated out if you like to do algebra tricks just to show off. Often scientific studies are done where a specific form of exercise is measured and so you can use other things in your formulas like average heart rate. But this is only good if you accurately measure and know your own personal constants. For example, your VO2max, so that you can accurately predict how much oxygen is being consumed, hence you are again back at METS if you want to be.

METS, or metabolic equivalents, are how many times harder you are working out as compared to if you were doing nothing. This number has been found experimentally for all sorts of things. You need to have a sanity check of course, as you can do just about anything at various levels of activity. For example, I could vaccuum the house at a pace that was easy and at a pace that made me sweat. I could lift the chairs and move the sofa or just hit the center of the room. So if you see a number for vaccuuming you have to also make sure it is equivalent to some other exercise where you know the number is valid. Typically, mph numbers on a treadmill are accurate because so much has been done to study these values. So you look at a table of activites to determine the METS of your activity. You multiply this by your BMR (calories per hour) to get how many calories you will burn in an hour of that particular activity. Part of the METS calculation has to do with how many muscles you use. So this is why bike riding is fewer METS versus an elliptical trainer if you do what you percieve to be the same effort, more muscles are being used for the elliptical workout.

Basal Metabolic Rate is measuerd by getting a good night sleep and then while awake but not stimulated, that is no coffee, no stress, just sit and relax and breathe into the tubes tied onto your face as if nothing was wrong. The digestive system needs to be inactive, so, no eating while you sleep either (for 12 hours actually). It is measured directly by measuring the heat your body gives off, or indirectly, by measuring how much oxygen you consume which correlates nicely to the heat thing. There are many formulas for getting an estimate and they are all based upon trying to predict how much oxygen per body weight is going to be used while resting. It is measured as energy per time usually calories per hour is what you will want to calculate. There are many online calculators for this, the simplest one I saw was 11 times your weight for a man and 10 times for a woman. This one is incorrect though. This is per day so you must also divide by 24 if you want the hourly rate. There are two good equations to use for an estimate that gets you close to each other so either can be used. I substituded english units because, although the metric system is great, I don’t use it, and this is for me after all.

Mifflin formula

  • For men: (4.53 x weight(lbs)) + (15.88 x height(inches)) – (4.92 x age(years)) + 5
  • For women: (4.53 x weight(lbs)) + (15.88 x height(inches)) – (4.92 x age(years))  -161
  • The Katch-McArdle formula is the same for men and women as it uses lean body mass, instead of weight, which is just subtracting 1 from the percent of fat, so 30% fat would use 0.7 in the equation (BMI is not body fat percentage by the way, it is a slightly higher number). The BMI to body fat calculators are not perfect so unless you know your body fat by a more accurate measure you might as well use the first method.

  • 370+ ((9.8* weight(lbs)) * (1-percentage of body fat)
  • For me the numbers are 1845 and 1794.

    This is not the number of calories we must eat to maintain our body weight, it is 1.2 times this because of what is called the thermic effect of food. Basically, it takes calories to digest food, so you have to eat 20% more than you thought to get the number you were looking for. Then of course this number assumes you sit around doing nothing all day, so you add calories for ALL activities if you want to see how much you need to eat exactly. Or in my case how muc of a deficit is created by eating less than this number. If you lead a very active life you might need to eat 90% more, or very sedentary is only 20% more. This activity of course assumes workouts and such, i.e a very active person works out 4 times a week. But since I don’t want this number, I want to put that in the workout deficit column, so I will just use 20%. Any extra in there is going to have to do with the general activities I do such as working at a desk is more than my BMR, walking around in a store, and even the EPOC is going to be a part of this calculation. For me all of this stuff is “gravy” for now. It is a non-zero number that gives me a boost, if I can keep the other stuff where it needs to be I can lose weight for sure, this just makes it come off a little faster than I could calculate. This is going to be true for anyone as well, even the sedentary person. There is just less “gravy”.

    So 1845/24 gives me my METS 1.0 calculation = 77 calories per hour per METS. So if I engage in an exercise that is 10.0 METS, I burn 770 calories per hour. An example of 10.0 METS is running on a treadmill at 6.0 miles per hour. Here is the most complete list out there. If you do certain exercises often and want to calculate in a different way, you can certainly do that. But this is going to be as good as any method out there unless you are a research scientist or doctor and have access to all sorts of special equipment to measure it more closely.

    So the short, step by step version is:

    1. Calculate your basal metabolic rate (BMR) using the formula above. (for me 1845 calories)
    2. Multiply BMR by 1.2 to find how many calories you need to eat a day to live a sedentary lifestyle. (for me 2214 calories)
    3. Divide BMR by 24 to determine a 1.0 METS. (for me 77 calories per hour per METS)
    4. Get a list that shows the METS equivalent (see above) or learn how to estimate it based on your activity level. Multiply these out times the hours to get your activity deficit. (For example, 30 minutes at 6 mph on the treadmill, (10 * 77 * 30/60) is 385 calories for me)
    5. To lose weight using the biggest loser method multiply your weight by 7 to get the number of calories to eat, subtract this from your BMR to find your food deficit per day. (for me 758)
    6. Add up all your deficits, you would include all activities not just workouts if you want an accurate number. (for me I am getting about 1000-1300 a day)
    7. Everytime you accumulate 4000, you lost a pound of fat. Be sure you are not working out in a way that will burn muscle off. This is why the biggest loser diet has you doing weights or resisitance workouts to be sure you are building or at the minimum maintainning muscle.

    Nutrasweet is unsafe?!

    June 20, 2008

    In honor of one of my favorite shows on the radio, called Science Friday, I decided to do a little research today, Friday, into my diet in a scientific direction.

    So I got to thinking about the NutraSweet thing and thought I would look into it. I vaguely have the notion that NutraSweet probably isn’t all that good for a person, but neither is 12 teaspoons of sugar worth of high fructose corn syrup that you will find in a can of normal soda. So first let’s tackle the sugar equation to verify it.  

    So I figured it out and it was too much math. I will give the result and suggest you don’t read the section below unless you really care about how I came up with the equations. There are two equations. You choose which one you want based on the more reliable number. If you know how many calories there are due to sugar then you can calculate the teaspoons by dividing by 16.14. If you know how many grams of sugar carbohydrates there are you can divide by 4.17 to get the equivalent teaspoons of sugar. A 12 fl oz can of Coca-Cola Classic has the equivalent of 9 teaspoons of sugar. A 12 fl oz can of Pepsi’s Mountain Dew has the equivalent of 10 1/4 teaspoons of sugar. The worst offender I could find is Jones Cream Soda which has the equivalent of 11 3/4 teaspoons of sugar based on the 190 calories. I am not positive the can has 190 calories some of these nutrition websites look a bit shaky to me I will have to check it out next time I find myself in the supermarket.

    Too Much Math it gets hard to read but I wanted to show how I calculated this stuff…

    They give you stats for 8 fl oz of coca-colabut a can holds 12 fl oz, brilliant. It says 27 grams of carbs but it actually has to be 25.06 to get the 97 calories. Each gram of carbs has 4 calories (actually 3.87 if you do the math on sugar 774/199.8=3.87) . Since a teaspoon of sugar is 4 grams, (actually a cup of sugar is 200 grams and a cup has 48 teaspoons so its 200/48=4.17). I love how the field of nutrition just rounds all this stuff to even numbers…

    [On a side note can you guys tell yet that I am an engineer? Who else would care about the actual numbers being so precise. Sometimes I wonder about me.]

    The final tally goes something like this. We have 37.6 grams of sugar when you scale up to the actual size of the can is 12 fl oz not 8. (Remember I used the 97 calories to get this number not the listing of grams which it doesn’t say) If you divide that by 4.17 grams/teaspoon you get 9.02 teaspoons. We can safely round that to 9 cause I can’t measure a teaspoon that close anyway. (the trick is not to round off until you are all done cause if you just rounded everything before you get errors. You would get 27 grams*1.5=40 grams then 40/4= 10 teaspoons which is too much). So take the calories due to sugar and divide by 16.14 (3.87*4.17) to get the equivalent teaspoons, or take the grams of sugars and divide by 4.17. Sometimes the carbohydrates are not broken out into sugars so you have to decide which number is better. This is easy for soda, there is no protein or fat so you can use the calories as the more accurate number. 

    So one day soon I think I will test the myth that there is so much sugar in a can of pop that it won’t all dissolve and that is why they use corn syrup. Will 9 to 12 teaspoons of sugar dissolve into 12 fl oz of carbonated water?  And, by the way, my recollection that there are 12 teaspoons of sugar in a can of pop was incorrect after all. It’s only 9 or 10 for most popular ones, but most people calculate it wrong and in my defense I just believed them.

    So now back to the evil topic of the post. [It only took me 700 words to get to the point.] Let’s compare 10 teaspoons of sugar to instead ingesting aspartame which is labeled as Nutrasweet and Equal. Nutrasweet is made up of three things, one of which alarms me. The first two are amino acids. There are 20 amino acidsthat make up the building blocks of protein, anything considered complete protein has enough of all 20 for human needs, they are each needed in varying amounts though. Sometimes proteins are incompleteand must be paired up with another incomplete protein that has some of the amino acids the other is missing. For example beans and rice.

    NutraSweet is made up of phenylalanine (50%) and aspartic acid (40%). It wouldn’t at first seem a big deal that we are consuming two amino acids of which we consume throughout the day anyway. But the concern raised is that aspartic acid is a neurotransmitter and in high concentrations can cause trouble in the nervous system such as aberrant neuron firing and cell death. There are many other probelms to that can be read in the article published in oygen magazine that I am linking to. When consumed in an isolated way the body can digest them more quickly which allows for higher than normal concentrations of these two amino acids. It is pretty obvious to me that this is probably a valid point. The digestive system will have to work for quite a while to tear up and digest that steak I ate last night while making quick work of a powder I dissolved into my chai tea.

    So even if none of this is true about the amino acids being a problem the last ingredient is definitely a problem. It is Methanol (10%). You can buy pure methanol at the race track (drag racing fuel) or at an auto store (Heet brand fuel line anti freeze in the yellow bottle). I know about methanol from my investigations into the process of making biodeisel from oil such as from waste oil used in restaurants or directly from the fields if you are willing to pay for the fresh corn or other vegetable oil. The instructions for making bio-deisel include a chemical process to take methanol mixed with a sodium or potassium hydroxide to create a very dangerous substance used to remove the fatty acids from the oil so they don’t gum up a normal deisel engine. The compound is only a catalyst and methanol must be removed/recovered from the unfinished bio-deisel at the end. All of the instructions go to great length cautioning you to be very safe with this very dangerous substance. And here I am drinking it with my chai tea!

    Another term for methanol that might be more familiar is wood alcohol. It is what moonshiners that make a bad batch are killed by. Now I am sure that the process does not involve simply mixing these three ingredients together in a blender but the chemistry term for aspartame is 1-aspartyl 1-phenylalanine methyl ester. In my study of bio-diesel there was a methyl ester created in the process of mixing the potassium hydroxide with methanol. And another chemical process that occurs with simply dumping the mix into a heated pan of oil brings the methanol back out. My body is sort of like a pan of heated oil and I am relatively certain that my body which is made to break things down can pretty easily remove the amino acids and be left with methanol. In fact here is a scientific book that talks about feeding this stuff with radiation in it to various animals to see how it is digested by where the radioactive atoms are expelled. The point I take from all these links combined is that the methanol is not a substance locked up in some chemical bond that cannot be digested by the body. So indeed I am actually drinking methanol, a known poison, with my chai tea. The methanol once released starts producing things in the body like formaldahyde which is a poison too, this is the same fluid used in the embalming process.

    I think I will switch to Splenda. I haven’t been this scared of my food since I saw Super Size Me.