How to really measure Weight Loss.

Measuring your weight is useful. Long-term fat loss is almost always accompanied by some weight loss. But it is important to understand the limitations of using scale weight as a progress-measuring tool. Your bodyweight represents much more than just fat mass. Changes in muscle mass, water retention, glycogen, etc. all influence your bodyweight development.
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For instance, now that many people will start going back to the gym again, it is likely that you will experience some weight gain during the first few days of training. This is because your body stores more glycogen (= carbohydrates stored in muscle) and this results in more water retention [1]. If you were to be overly focused on losing weight, the slight spike in bodyweight after getting back into training could leave you discouraged, but this is not fat gain.
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Also, it is possible that now many people will regain some lost muscle because they are able to lift heavy weights again. If this happens, it is likely that your rate of weight loss slows down. If you regain muscle while losing fat, typically your bodyweight won’t change as quickly since the loss of fat and the increase in muscle mass balance each other out [2].
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This is why I suggest you track more progress measures than just bodyweight. In the last slide of this post, you can find an overview of my suggestions. By also having body measurements, progress pictures, and tracking performance, you get a better view of your overall progress. So that even when your weight loss stalls, you are able to see whether it’s a true fat loss plateau or you can continue according to plan.
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1. https://pubmed.ncbi.nlm.nih.gov/25911631/
2. https://pubmed.ncbi.nlm.nih.gov/20309749/