The Analytics Behind Losing 15kg in 3 months

This summer I decided it was high time for slimming down, mostly because I got tired from the simplest things – like going up the stairs for 4 floors. So in the way worthy of a project manager with engineering background, I set an objective, I made a plan and I started tracking the metrics. After all …

You cannot manage what you do not measure.

Start weight: 108 kg

Target weight: 93 kg

Delta: 15 kg

Budgeted time: 4 months

Targeted loss/month: 4 kg /month


Below, you can find the charts. I did not use any real time apps, or gadgets or wearables. I’m old fashioned like that: analog scale and Google Spreadsheets.


Weight loss plan: target vs. real


Above: Real measured weight is painted in blue, while the (linearly) planned target weight in painted in red.


Delta Weight

Above: the “ahead-of-plan” metric (also called “buffer”), as measured as planned weight minus real measured weight.

Note that the points in the chart are not equally-spaced.


Average Variation

Above: the average daily loss. Note that the points in the chart are not equally-spaced.


My conclusion from this 3 month+ experience:

  1. Measuring relatively often keeps you focused, as in allows you to reinforce a concrete, practical small target every few days (or once a week), rather than a big monthly target.
  2. No matter how disciplined one is, weight loss does not occur at a constant pace. Some weeks you exceed you target, some weeks you miss it. See the average daily variation chart.
  3. Weekly targets don’t matter that much on the long term, but they can motivate and drive your actions and choices (i.e. salad instead of pizza, orange squeeze instead of Cola) on the short term. Missing a target every once in a while is good if and only if it motivates you.
  4. Don’t obsess over daily micro-measurement. Some days you are better hydrated before you measure yourself and some days you are less so. Therefore, it can seem you suddenly gained 1 kg, when there is no actual change. Always assume there is an inherent daily “noise” in your measurement which evens out on the long term (weeks, months). To even out the noise, try to do all measurement at the same time of day, using the same scale. Note: I have not kept daily measurement, so that noise is not visible on my charts.

All in all, now I feel much better. And I’m very proud of my analytics.

Bogdan Written by: