For those of you who want to track your weight but have anxiety with weight fluctuations...try this

Aaron_K123

On the forums here I see daily posts about how someone just stepped on the scale and it read 3 pounds higher and they felt devastated and like they had lost all of their progress. They maybe told that random weight fluctuations are to be expected but it is hard to see that when you just look at single scalar measurements.

So try a moving average instead to smooth out the error associated with your measurements.


Here is my weight tracked almost daily over the period of a month plotting the scalar single measurements over time.




What a mess right? How can you see anything in that garbage...is my diet working? Am I losing weight? Doesn't feel like it and it doesn't even look like it...its upsetting right?

Now here is that exact same data calculated as a moving average.



From this I can apply a fit and from that fit I can calculate that over that month I was losing a pretty consistant 0.5 pounds per week...the overall trend is clear. If I want to lose more then I know I need to adjust my diet and continue to track and see what happens to the slope over time.

Last time I lost weight I also used a moving average, with more data and more time it smoothed even more until my progress was very predictable and easy to track.



Over that period of 5 months I lost pretty consistently 1.1 pounds per week. The longer you are doing this as long as you are consistant with your diet the clearer the trend will become.


So what is a moving average? Its super simple actually.

If you measure your weight daily each datapoint is a scalar value. Lets say you track your weight by day and it looks like this:

1 180
2 179
3 177.8
4 179
5 179
6 179
7 176.8
8 179.2
9 179.2
10 179.2
11 180
12 176.8
13 176.8
14 176.4
15 178.2
16 178
17 178.2
18 177.2
19 177.2
20 177.2
21 177.2

A moving average has a period, the larger the period the more smoothing you will do to the data. Lets pick a period of 8. What that means is that on a given day your value is the average of 7 days, 3 before and 3 after plus what you just measured.

So it looks like this:

Moving average
1
2
3
4 178.7
5 178.5
6 178.6
7 178.8
8 178.9
9 178.6
10 178.3
11 178.2
12 178.1
13 177.9
14 177.8
15 177.4
16 177.4
17 177.5
18
19
20
21



So basically on Day 4 in this example the weighted average is the average of your weight on Day 1 through Day 7 while on Day 5 the weighted average is the average on your weight on Day 2 through Day 8 and so on. Notice how much smoother then transition day to day becomes then.



This certainly isn't necessary to do, but if you have high anxiety from your scale but can't bear to not track your weight you might want to give this a try. It will turn the scale from something you dread to stand on to another datapoint for your ever increasingly accurate tracking.

Mentali

I know there are some people that have scales that upload their weights automatically to a site that does a trendline instead of each weight. Is that the same idea as what you're talking about? That way the person doesn't have to look at the actual weight, but can look at the trend to make sure they're on the right path.

AnnPT77

There are apps you can get (free) that do something similar: Happy Scale (iOS), Libra (Android), Trendweight, others. Not a panacea - like, sometimes my trend line lies, especially in maintenance - but it may help some folks during weight loss.

sky_northern

trendweight does same kind of thing. I have a scale that connects over wifi and so I don't even have to look at the number when I weigh in, I can just pull up trendweight latter to see if I'm on track.

Aaron_K123

Not the same as just a trendline no, if you tried to fit a trendline to the scale weight in the first graph it wouldn't be a good fit. Moving average is to average out (smooth) the noise that is associated with weight fluctuations due to things like water retention from sodium or other reasons. With the moving average ploted the trendline will yield a much more accurate slope. That final graph is a 7-period moving average with a trendline fitted that shows over that period I was losing at a very steady 0.16 pounds a day (the slope is weight lost per day).

sky_northern

Trendweight uses moving average (based on Hacker's diet) not trendline, despite it's name.

Aaron_K123

Yeah I'm sure there are lots of free online tracking tools that do the same thing, not trying to claim I'm inovating or anything...just responding to the seemingly neverending questions about "Oh no my weight went up today what am I doing wrong?" type posts.

hjlourenshj

i also track and use the same but average from last 7 days. So i can see my moving average from today! not my moving average from 4 days ago! ;-)

AnnPT77

Aaron_K123 wrote: »

Yeah I'm sure there are lots of free online tracking tools that do the same thing, not trying to claim I'm inovating or anything...just responding to the seemingly neverending questions about "Oh no my weight went up today what am I doing wrong?" type posts.

And that's a wonderful thing - I admire what you're doing. Weight loss just seems like kind of a fun science fair experiment for grown-ups, to me, but not everyone's wired that way. I just thought I'd mention the apps because some folks aren't as cozy with calculating things themselves. (And, AFAIK, what they're doing is calculating a moving average or applying some similar smoothing approach.)

That all said, there's no calming some folks via stats: I remember one thread in the forum where a guy (the OP of that thread, IIRC) was deeply upset that the weight trending apps were not telling him his exact true weight every day, irrespective of fluctuations.

sky_northern

Aaron_K123 wrote: »

Yeah I'm sure there are lots of free online tracking tools that do the same thing, not trying to claim I'm inovating or anything...just responding to the seemingly neverending questions about "Oh no my weight went up today what am I doing wrong?" type posts.

Yeah, for sure that is awesome. I was just clarifying that what I use does that without me having to do the math myself. You make a good point, but some people are scared of math so knowing the tools that they can use I think is a good thing.

Aaron_K123

hjlourenshj wrote: »

i also track and use the same but average from last 7 days. So i can see my moving average from today! not my moving average from 4 days ago! ;-)

Yeah you can slide it whichever direction you want, have it centered or have it on one end. My example had it centered but I could have taken the average over whatever period (like 7 days) and had each day be the average of the previous 7 instead of the last three and the next three plus that day. Overall it doesn't end up changing the result in terms of the trend.

Aaron_K123

@AnnPT77 "Weight loss just seems like kind of a fun science fair experiment for grown-ups"

Yeah thats how I view it. Something to play with and mull over and learn about your own body. But I'm not going to mock someone who has fears associated with it, I get people are different.

"AFAIK, what they're doing is calculating a moving average or applying some similar smoothing approach."

No-no, they are using WeightLossCo's patented neural network to extract your true weight from the randomness a normal scale would provide you (or whatever other techno-speak garbage companies use to refer to them just using a moving average).

sgt1372

I weigh myself daily and use a free copy of Excel to track the data and compute a 7 day moving average. It's easy.

I also post my daily weight on MFP and it would be nice if MFP added a feature to compute a graph of the 7 day moving ave as well. Don't think it would be difficult or costly to do.

Aaron_K123

sgt1372 wrote: »

I weigh myself daily and use a free copy of Excel to track the data and compute a 7 day moving average. It's easy.

I also post my daily weight on MFP and it would be nice if MFP added a feature to compute a graph of the 7 day moving ave as well. Don't think it would be difficult or costly to do.

Yeah I do the same, at least I do once I have a couple months worth of data to start with (I don't typically bother until then I just did it to provide an example).

It would be stupid simple for them to implement that yeah, but they have no reason to really unless people ask for it and people won't ask for it if they don't know what it is. Its like a one step equation its not exactly hard to code.

AnnPT77

Aaron_K123 wrote: »

@AnnPT77 "Weight loss just seems like kind of a fun science fair experiment for grown-ups"

Yeah thats how I view it. Something to play with and mull over and learn about your own body. But I'm not going to mock someone who has fears associated with it, I get people are different.

"AFAIK, what they're doing is calculating a moving average or applying some similar smoothing approach."

No-no, they are using WeightLossCo's patented neural network to extract your true weight from the randomness a normal scale would provide you (or whatever other techno-speak garbage companies use to refer to them just using a moving average).

LOL - and all that in a free app, besides!