Bio impedance discoveries


(charlie3) #1

I got a bio impedance smart scale on Amazon last September (Renpho). One of my goals for resistance training was to gain a pound a month for 24 months. Last fall I got concerned it wasn’t happening. Over training is the usual reason so I reduced my 3 times a week workouts from 3 sets of 10 exercises to one set of 10 exercises. Session time went from 60 minutes to 20 minutes. I hated it but it worked. I have high confidence because of 6 months of bio impedance data.

This first screen shot from the Renpho app is muscle mass. The first data point is September 30th. Each point is the end of one month. I went to single sets at the beginning of December, the third dot. That’s when progress accelerates. The graph starts at 120 pounds of muscle mass. Over 6 months increases to 128 pounds. That is just a bit better than a pound a month, right where I want to be.

The chart below is fat free body weight covering the same 6 months as above. The change 126.2 to 134.8, a change of 8.6 pounds

Finally overall body weight, 143 pounds on 9/30 to 155.2 pounds on 3/25, a change of 12.2 pounds. So may be a pound of muscle is costing me half a pound off fat. The trade of is not so bad because I started zero carb on the first of March and hideously over eating.

The above gives me more confidence to continue a one set approach. Before making this post I researched other smart scales besides Renpho and couldn’t find a reason to recommend some other one. If some one knows more about smart scales than me and has personal experience with a better one please chime in. I’m ready to invest in a better smart scale if such a thing exists.


P.S. A few more points.

The Renpho scale estimates my bone mass increased from 6.4 to 6.8 pounds, a few ounces. It’s interesting that the improvement didn’t start until after I reduced sets to one per exercise so may be my bones weren’t recovering either. A few ounces might not seem like much but when you’re 70 years old it’s nice to see that number go up instead of down.

Another interesting trend Renpho estimates is my BMR, sedentary calories per day. As with the other positive trends it was creeping up at best until I reduced the volume of lifting.


12 hours in on first fast in 30 years!
(Allie) #2

If overtraining is a concern you may want to check out heart rate variability.

I use HRV4TRAINING on a daily basis, just takes 60 seconds each morning before getting out of bed.

https://www.hrv4training.com/ - site is down at the moment for maintenance but it’ll be back soon.

I also use the Renpho scale you have and way prefer it to the Tanita I used to use.


(charlie3) #3

Thanks much for the HRV tip. I’ve been aware of that for a while but haven’t figured out enough to get started. I paid the money, got your app (a leap of faith), passed the signal quality test and recorded the first data point. Do I limit this to one time per day?

I was a hobby lifter years ago. My physique model is a 19th century farmer or stone mason. In the days before electricity and tractors lots of people had serious muscle. Back and legs get most of the work because that’s where the muscle is. I don’t do isolation work on arms.

I have a decent basement gym that has been waiting patiently for me to get interested again, which happened a year ago. Goals are the same as 25 years ago but priorities are reverse order. Back in the day I thought I was exploiting metabolism to build muscle. Now I’m exploiting muscle to strengthen metabolism. I don’t want to gain as fast as possible. I want to gain for as long as possible.

I try to keep reps higher than 12 to minimize wear and tear. The convincing science I’ve found is that higher reps grow muscle just as well as lower reps at my intermediate level and 48 hours is the ideal rest interval. With those constraints one set per exercise every 48 hours seems to get the best results for me, for now. I care about hypertrophy but only look for strength gains, meaning adding a rep and/or adding a couple pounds to the bar. I figure as long as strength is increasing hypertrophy has to follow at some point.

Thanks again


(Allie) #4

Yes one measurement each day, ideally at the same time - it limits you to just one and will over-write results if you re-test. In the app set up you can enter a preference for measuring either morning or evening. I always do morning about ten mins after waking but while still in bed so as to get the measurement recorded before I’ve done any sort of activity or consumed anything at all. You’ll need to measure for a few days in a row to establish a baseline then the app will be able to guide you.

I tend to switch up my training the same as I switch up my eating windows, constant variety. Sometimes high reps low weight, other times lower reps high weight. On heavier days if I can comfortably complete 3 or 4 sets of 12 then I increase the weights. Lighter days I tend to do 3 or 4 sets of however many reps I can do, normally around 20 - 30 each set.

Routine wise I alternate between a pull / legs / push / legs routine and a single body part split (chest / shoulders / legs / back / arms) combined with almost daily yoga and without fail daily meditation. On the days when the HRV app advises me to take things easy, I limit to just yoga & meditation, maybe sometimes some gentle cardio but I walk miles each day so don’t often feel the need for additional cardio work.


(charlie3) #5

So I’ll try to keep the morning habit. Do you find the app’s advice about rest holds up in practice?

In younger days I expressed the typical ambition towards lifting, to gain as fast as possible. That is a risky goal. A kid says he wants to drive his car as fast as possible. He pins the accelerator pedal to the floor and steers until he loses control and crashes. That is pretty much what happens with gaining muscle “as fast as possible”. It works until over training or an injury interferes. So I’ll go slower on purpose, stay with a pound a month, even if progress could be faster.

In the mean time going to ZC is more disruptive than I expected, mostly satiety issues. May be HRV will help with that too.


(Allie) #6

It certainly seems to yes, and it knows before I do too - some mornings I feel fine but it tells me to be careful, then when evening comes (my usual training time) I realise it’s right.


(charlie3) #7

Paul, I was asking the butcher to add fat to the chuck he was grinding for me. That seems to make no difference. Food has a big psychological factor. The solution will probably be specific to my temperment. I’ll be surprised if I learn to rest easy on animal products only. In the mean time I’m excited by some recent discoveries on the exercise front.

I took another careful look at 7 months of Renpho scale, training, and nutritiion records and come to some surprising conclusions with high confidence.

  1. I gain muscle mass at the same rate whether doing 3 sets of 10 exercises 3 times a week or 1 set of 10 exercises 3 times a week. (I’m convinced the gains are faster on the single set routine. I call that hyper resonsive, not newbie gains. Gains come easier if the lifter is not over trained, usually caused by over enthusiasm.

  2. I do 60-80 minutes a day of brisk walking and about the same amount of cardio on an airbike most every day. May be I would gain muscle mass faster with less of this but it doesn’t interfere with gains above my pound a month goal.

  3. I can accomplish the above eating maintenance calories at less than 30 net carbs.

The next challange is to see if I can keep adding a pound a month of muscle and get rid of 5 pounds of fat over a couple of months.

To keep it simple, what shouts out to me is I gain muscle mass as well or better on 1 set of 12 exercises 3 times a week as 3 sets or 2 sets 3 times a week. One set of 12 exercises means a 30 minute workouts. For now doing more is a waste of time and energy or worse.


(Bob ) #8

@Charlie3, I realize this hasn’t been updated a while, but I wonder how your progress is going. I find your gains interesting to say the least! Especially where you say, "I gain muscle mass at the same rate whether doing 3 sets of 10 exercises 3 times a week or 1 set of 10 exercises 3 times a week. "

You said you’re 70; I’m a few years younger than you. While I’m primarily a cyclist for fun, we have a Bowflex that I still haven’t maxed out on. Somewhere I got the idea I didn’t need to do more than one set to exhaustion once a week. I’ll be stepping that up.

I’m also interested in the Renpho bioimpedance scale. I have an old Tanita (I mean like late '90s) and really don’t know how it compares to anything newer. I saw the Renpho and was skeptical it could really measure all they’re claiming. It does so much more than the Tanita does!


(charlie3) #9

I have learned a lot with the Renpho scale. I measure once a day, first thing in the morning but draw conclusions about trends every two weeks to a month. It’s hard to go wrong at that price. If I knew of a superior system I’d get it.

I think the most important mistake lifters make getting started is to decide they want to gain muscle “as fast as possible”. If they stick to that injury is the inevitable outcome. Ironically fast as possible means what ever happens, good or bad.

I decided the goal would be 1 pound a month and no faster and I’d do the minimum amount of exercise to accomplish that. So far the right amount has been 1 set of 10
exercises 3 times a week. That volume could go up or down depending on training status but so far it’s been just about right. Actually I’m putting my lifting frequency to the test this week, a long Memorial weekend, by taking a break. Then I’ll see what happens coming back. I suspect I’m a bit over trained at the moment even at the reletively low volume because I tend to make the sets very intense. If you are getting along with one session a week may be that’s okay. Are you maintaining or gaining strength with once a week?


(Allie) #10

One glitch I’ve noticed with my Renpho is it always adds a couple of pounds the first time I step on it. I’ve started weighing twice each time now as the first time it’s always higher, but the second (and every other time afterwards, I’ve tested repeatedly) it gives a more accurate reading.


(Bob ) #11

Thanks for the input. I’ve been gaining some strength with lifting once a week. The first few weeks were faster - I guess the first bit is always easiest.

Maybe it’s because I’m a retired engineer but I really like your methodical approach. I’m not attracted to the “as fast as possible” view, probably because I’ve been down the road and hurt myself years ago. A pound a month is fine.

I also really like your analogy of life a hundred years ago. My main goal is just more strength for life. Something always has to be moved, or we have to put up the hurricane shutters or something.

As I mentioned I have a Bowflex, and I’ve always felt like the rubber rods have worn out and aren’t putting up the resistance they used to. I finally got a way to check what the weights really are and the resistance I’m getting is about 25% of what it’s marked. Some online checking shows that’s not an uncommon finding. I figure as long as I’m getting some hypertrophy, it doesn’t matter what the rubber bands say but I will tap out the machine sooner than if the numbers were right.


(Bob ) #12

That’s interesting. If you stand on it for a while, does the weight go down, or does it turn off and you have to start over?

I think I’m going to grab one of these.


(Allie) #13

Once it’s recorded your weight that’s it, it doesn’t change. But if I step off again, wait for the display to turn off, then step straight back on, I’m magically 2 pounds lighter. At first I thought it was caused by electrical interference from my Garmin watch as I would step back off, take it off, step back on and be lighter but now I know it’s just a glitch as it happens with or without the watch.

Interestingly this happens only first thing in the morning, not at any other time of the day. Just odd.


(charlie3) #14

The documentation, the last time I looked at it, seems to say the scale wants to be calibrated before each use. I do that by putting most of my weight on the scale and stepping off the moment it lights up. Then you should see “CAL” and then “00”, and then it should be ready to use. The pound a month goal didn’t work well until I got the scale.

What I learn from the scale is the increases in muscle mass come in fits and starts. One month will be 2 pounds, another month will be zero. I’m finding the most important thing is to avoid over training. You can over train and grow more muscle for a while then you’ll stall or get an overuse injury. I avoid all that by choosing to grow slow and steady with absolute minimal sets and lift at the higher end of the rep range where weights are lower andinjury risk to joints and connective tissue is reduced. (If I can add 25 pounds in 2 years I’ll look like Superman–retired. I don’t fly any more, FAA revoked my ticket because I couldn’t pass the eye test. Superman retired kicks sand in the bad guy’s face then runs away, really fast.) To benefit from large volumes of lifting you need to be taking drugs for faster recovery. I want to look like I got it the hard way. The world gives that more respect.

If I didn’t say already, collect several months of daily weigh in’s before expecting useful summaries. For instance, if I train 15 times a month to gain a pound of muscle that’s 1 ounce per workout. Of course the scale can’t detect that. I have 8 months of daily data. That tells an interesting story, especiially when I match it up with my training log and Cronometer data. None of this is perfect but there is good enough resolution to gain insights.

Dieters want to reduce fat, not muscle. The Renpho scale will help keep track of that, at least month to month.


(Bob ) #15

At this point, it will be interesting to switch over to the new scale (will be here tomorrow) and compare data. I’m sure it will take a few weeks or a month to get a baseline. Thanks for that tip about stepping on the scale to get the “CAL” then “00”. My 20 year old Tanita has a turn on procedure where it does some self checking and then displays 00, too. You don’t just turn it on and step on it.

Maybe a year ago, I saw a scale like the Renpho (might have been one) and was surprised at what it said it can do. I know these products tend to get better over time as the engineers figure out new tricks, but the difference from mine was amazing. Since the one thing “Everybody Says” about the bioimpedance measurements is that they’re not accurate, I was skeptical it could do everything it claimed. My Tanita tells me the weight and %BF well enough to track changes. It might not be accurate compared to a DEXA scan, but it’s repeatable and that’s probably good enough.

I have a lot of fat to lose. According to my Tanita, I’m 26% BF, so 52 pounds of fat, and I’m sure there’s at least 10 or 20 to lose - not even in the same zip code as my ideal weight. A while ago, I did the tape measure method (Navy?) and got 2% above what the scale said, so I just averaged them. I fully expect the third reading from the Renpho to come out somewhere close to the other two.

Of course, I’m more interested in losing fat than losing weight, but on a week by week basis it’s hard to tell (like you say). I’m doing alternate day fasts, which work out to be about 42 hours. I always bike while fasted, and haven’t thought about being fasted or not when I lift.

I have a lot of things to figure out. This week, after three 42 hour fasts, according to the scale I didn’t lose any weight nor did my % bodyfat change. Did I re-proportion something positively? Those numbers are plus or minus 1 lb at best, so it’s possible, just like you say about needing time to see results in muscle gain.


(Chris - carnivoremuscle.com) #16

@charlie3 have you heard of a Skulpt device? It’s a handheld impedance scanner that you use on specific parts of your body, it’s supposed to give the most accurate bioimpedance reading of all the devices. Costs 99$ I think, however, so it’s a bit of an investment vs. a Renpho.

I haven’t taken the plunge on any of these items personally, my gym has an inBody scale which I use from time to time before I train. My only issue with the Renpho the reviews online are not terribly credible sounding. I searched for a few hours and only found what seemed like purchased reviews. Not saying I don’t believe you but it’s my inner skeptic coming out.


(charlie3) #17

At a minimum the Renpho tells me what direction things are going. It helps with discipline. I would love to have a more accurate smart scale assuming there is such a thing. My understanding is the scale only needs to produce an accurate and consistant electrical impedance reading. After that it’s all about the software. Accurage digital weigh scales don’t have to be expensive. It seems that the hardware for the impedance measurement also doesn’t need to be expensive ergo, the scale doesn’t have to be expensive. I wish a bunch of people weree using them and comparing notes–learning from each other. To support that I’m willing to give some support based on my almost 9 months of experience with this particular scale and the app.


(Bob ) #18

I hadn’t heard about the Skulpt @Dread1840, so did some reading; learned about the AIM and the Chisel, read a bunch of guys’ reviews. Interesting device.

For one thing, I wonder if it’s doing what I really care about. Since it’s measuring impedance on specific muscle groups, and telling you the percentage fat in that area, is it missing visceral fat? That’s what they say is the most dangerous.

It seems it’s best for body builders and targeted at that market; they probably do care more about percent fat in those areas than one overall number so that they can look best. Also, if you’re training for more muscle symmetry (or recovering from an injury in effort to get symmetry back) it seems practically indispensable for that.

The problem with body fat measurements is like that old saying, “when all you have is a hammer, every problem looks like a nail”. If you get a number that’s higher than you want, all you know is to reduce that number. Weight isn’t a good metric to measure our health by and I’m not sure % body fat is a heck of a lot better. A pound of fat in your liver is worse for your health than that same pound of fat in your butt. Likewise, a pound of brown fat is better to have than a pound of white fat. One number for %BF still isn’t telling you much.


(charlie3) #19

Body fat comes and goes from where it pleases. I’m content with an overall measure.


(Bob ) #20

As they say, no such thing as spot reducing. It’s going to come off where it wants to. (My wife says “last on, first off”)