Mufasa - How's the Bioelectrical Scale Working

Hey Mufasa - I just wanted to get some feedback from you as to how your bioelectrical impedance scale is working for you. How often are you measuring and how reliable are the measurements. By the way, I submitted an article to TC about 2 weeks ago, but have not heard anything. Maybe he’ll take a look one day.

Hey, Jason! Thanks for asking! Your information has been invaluable in my understanding of these devices. Well…this is what I have so far: I use two devices, and have been using them in parallell: The Omron BodyFat Analyzer (Which is hand held, and doesn’t do your weight) and the Tanita 612(with “Adult” and “Athelete” settings).I weigh first thing every Monday morning, taking measurements with both settings on the Tanita .I am still gathering data, so I don’t want to make some profound statement like you often hear on the board (that goes along the lines of "don’t buy that man…it’s a piece o’ crap, man, and I hate mine, man!!!)However…I have been able to make some preliminary observations:

  1. The more “overfat” you are, the ACTUAL bodyfat level you are may be off, but I am seeing a consistency among the devices in monitoring overall trends.

  2. AT THIS POINT, the Omron appears more “stable” in terms of week to week fluctuations, but as I lose more fat, the two devices appear to correlate closer and closer, with the Tanita showing less fluctuations than it did at higher fat levels.(It will be intesting to see on the Tanita when the “Adult” readings will be the same as the “Athelete” readings, and at what bodyfat percentages this will correspond to).


    3)My own observations have shown that, in fact, inconsistency of diet, hydration status, and time of day can, in fact, effect the readings, with vast differences between a.m. and p.m. (All my data will come from a.m. readings, however, which according to both manufacturers, is NOT the best times to use the devices). When I gather these numbers AND gather comparative data on Pre-Workout/Evening Readings (which are recommended by the manufacturers for various reasons), I’ll let everyone know.


    THINGS ARE VERY PRELIMINARY NOW! So don’t anyone ask for numbers, percentages, etc., because I don’t want to become part of the “impedence device hating Hallelujah chorus.” From what I’ve seen so far,however, they can be effective, easy-to-use monitoring TOOLS…let me say it again…TOOLS…IF used correctly and to monitor trends.


    As you’ve said before, Jason…NO way of measuring, including hydrostatic, are going to be exact. We just have to stick with one, and use it 1)Correctly and 2) Consistantly. For me…I think that will be the impedence devices.

mufasa - i noticed some very cool trends over an 18 month period using my hand held omron analyzer as well. my analyzer seems to be a bit different than yours though. it has settings for up to four people consisting of height, weight, age and sex. it gives the LBM, fat mass and percentage to the tenth of a percent. i too HAD a tanita 612 and couldn’t get as consistent results with it and quickly sold it to a friend. i took three measurements per day with the omron first thing in the a.m. (preworkout and postworkout) and in the evenings. it was cool to see how your body stores, sheds and repartitions fluids through the course of a single day and in the long term as you either shed fat or gain muscle. i noted correlations between preworkout muscle volume, post workout pump, workout performance and strength gains. after gathering several months of data and taking careful notes along the way i found that days when i experienced increased performance i had registered a reading that indicated (based on similar readings and other readings in the vicinity) i was at maximum muscle volume. and i experienced extreme increases in post workout pump just prior to noticeable strength gains in conjunction with a proportionally larger bf% drop (as compared the trend at the time). these signs were very similar everytime i experienced a growth spurt. i think that if you take good data and pay close attention to your body (make note of even the most seemingly insignificant thing) you will see what i am talking about. i swear by these devices. good luck bro. kevo

Thank you for the replies guys. Unfortunately, at the moment, I only have access to a Tanita scale at work. It is the TBF-551 which has 4 memory slots, the athlete setting and adjusts in 0.1% increments. Although I do work in an exercise physiology lab, I can’t just strip down and hop on the scale anytime of day, thus I have not been able to utilize it effectively. I think I will try to bring it home and fiddle with some different ideas. For the past 5 months, I have been using skinfolds to track body composition and have been measuring weekly with my training partners although 2 times a week is the norm. I am not satisfied with my current tracking system and I think I’m going to modify it so that I can do everything at home on my own. I think I will use the 3 site skinfold equation (chest,ab,thigh) and also possibly buy an impedance unit. Mufasa - keep me posted on which device you believe is most reliable. That is a very important thing to know especially if you are going to fork over $100 for something. I’ve gotta run, but would like to discuss further. I think this area is a topic that desperately needs more clarification.

Here are a few other observations that I have noticed using the Tanita scale. Its reliability is very good within a session. I can take 5-10 measurements within a 10 minute time frame and each measurement is almost the same. About +/- 0.1% percent for body fat. As I mentioned before, I am only able to use this device during the day and this leads to inconsistent timing. I drink upwards of 2-3 gallons of water a day (especially with the new Surge dilution recomendations). Each gallon weighs around 8 lbs, thus I have huge weight fluctuations but it is all due to water. Therefore all the variability that I see in my measurements, I have to attribute to physiologic variations in my weight (due to fluid balance changes) and fluid balance changes rather than anything inconsistent with the measurement technique. Fluid balances with any bioimpedance device are a double edged sword because fluid variation changes weight and impedance leading to increased errors.

Anyways, enough rambling. You have to use these devices first thing in the morning because that is the ONLY time in an active athlete or bodybuilder that things are remotely consistent. As for the company's suggestion to use it later in the day, it just does not work if you are using the device religously to monitor changes.

Kevo - I am very intrigued and may end up trying something similar to what you did with the 3 a day measurements. The goal with keeping a training log, diet log, body comp log and what not is to stay on track but also is to find hidden gems withing all the data. How much science and discovery have come about due to accidents? Without detailed record keeping one will never know why something really happened the way it did.

Jason N - right on about the accidental discoveries. what i found to be the coolest thing was that during the first several months of collecting data i wasn’t even paying attention to what the data was saying. i was merely collecting data and taking notes. but then i started to notice things. ya know when you get the instinctive sense that something is happening, but you are not quite sure what, but you feel that it is something positive? i had an upsurge in these instincts during this period of time as i was becoming more aware of my body than i ever had before. and it wasn’t until after i seriously looked at the data and compared it to my training logs that i noticed the corellations. now i know what to look for in the data. along with my instincts the data confirms that what i am doing is working for me. without tracking body comp to this level and using the data as my road map all i would have is this “something seems different to me today. i must be doing something right” method of navigation. as a technical minded person needing to quantify things i hate flying without instruments. kevo

What else do you monitor on a regular basis. I am working on creating a daily spreadsheet where I keep track of pro, carbs, fat, fiber, cals for diet. Hours of sleep, waking pulse, morning weight and bodycomp. Weekly, I’ll add a skinfold caliper reading. Other options include waking temperature daily and possibly some girth measurements, but I don’t think I want to add those on a regular basis. Do you have any other ideas for simple items to track that may have an effect on one’s training program?

sounds like you got the right idea! kudos, bro.

on a daily basis i track morning weight & bodycomp (pre and post workout), evening weight and bodycomp, protein, carbs, fat, calories, sodium, water intake, weight before and after cardio (to track water loss), workout stats (sets, reps, strength increase / decrease, relative performance), perceived muscle fullness and appearance in the mirror. for a short period of time several months ago i tracked pulse rate, blood pressure and morning temperature, but i haven’t taken those in quite a while. every once in a while i will take my body measurements. i rarely ever take pictures, but prolly should.

for me at least it seems that many of the variances that are seen from day to day are due to nothing more than water fluxuations. hydrations levels or more importantly how the water is stored within your tissues (whether it be in muscle or elsewhere) always seems to be one of the most important factors for me. without fail i can always trace my progress or lack therof back to specific hydration scenarios.

impedance monitors track this sort of thing really well. if i get too lean though the analyzer won’t even register and it gives me an “E4 ERROR”. which means gain some more fat and try again later. the real trick is looking at the data in as many ways as possible, finding patterns and learning how to interpret it based on known principles. kevo

Thanks Kevo, I’ll let you know what I see.

I also have a scale and was experiencing wide fluctuations in the readings of bodyfat until I thoroughly read the manual. It said something about some people having a type of skin that can impede an accurate measurement but that it can be corrected by dampening your feet. I usually check the scale right after I get out of the shower and the results have been very consistent. Otherwise I just wipe my feet with a damp cloth.

B.Daddy…that’s interesting…I think that I’ll try the damp feet. I’ll let you guys know how the Tanita begins to compare to the Omron AND to see if there are those periodic fluctuations. Should be interesting!

(Is it BiG…or BiD(typo?))…anyway, Bro…I couldn’t find the info you quoted in the Tanita Literature…hope the post was legit, and not a “joke” for the T-folks!!!


Jason N.: In your experience, does the idea seem legit? (of moistening the bottoms of your feet) for the scale type impedence devices? Mufasa

obviously the dampening of the skin will help conduct the electric pulse a bit better. i noted differences between times when my hands were dry vs. moist (ie. winter vs. summer). callouses on the bottom of ones feet could be a factor as well as dry or oily skin. in general though both your hands and feet stay pretty much the same all the time and would prolly be canceled out as a reason for wildly inconsistent measurements. if your hands/feet are wet or dry or lotioned or whatever just make sure you are consistent with it and all should be fine. kevo

Of course, moistening the feet will help with conduction, but how much water should you use and is the external application of water at the conducting surfaces changing the measurement? I don’t think this is a good idea. Everyone I’ve talked to in academics that use biolectrical techniques say you should have WARM, DRY skin. If you are getting goosebumps and the skin is constricting, you won’t get good measurements. I would still stand behind my original suggestion, do it first thing in the morning after going to the bathroom. I have noticed that I get pretty cold very quick, so try to stay warm right out of bed. Then take the measurement again after you have completey dried off from your shower. Your skin should now be very warm and you should be able to conduct a signal better, but I think that your skin should be dry.

Fell free to try the suggestion of wetting the feet, but I don’t think it will help with reliability.

I’ve been thinking about the water question for a bit. I think that their might be some good rationale behind it after all. When using electrodes for bioelectrical impedance measurement, you want the skin warm and dry, BUT the electrodes which generate and measure the current are covered in gel allowing for better conduction. Maybe wipe the feet with a damp cloth and try the measurement, but no other part of the body should be wet.

Wow, I misspelled my own name. Duh!!

When I first got my scale there was a section starting with “a small percentage of people have skintypes …” blah blah blah. I just figured that I wouldn’t be in the minority so I didn’t even read the rest. Then I noticed wide fluctuations in my readings from day to day. I’m talking 5% changes. Then I went back and looked for that section and it stated that some skin types require damp feet for consistent readings. I’m not joking and ever since I’ve been doing that the readings have been constant.

To be honest I don’t even really care how accurate the readings themselves are (to a point) as long as they are consistent. As long as it tells me if my bodyfat is going up or down compared to my last reading then that is information that I find useful and use to determine what diet and activities negatively or positively affect my body.

As someone else said, these things may not be perfect, but if you use it simply as a tool, they can be a great help.

Thanks, Big! I think I’m going to start the parellell measurements with dry and damp feet. I’ll keep you guys updated…Mufasa