Your watch is not lying, but it is not telling the whole truth either.
This is one of the most common ways weight loss stalls in the real world. People train harder, close the rings, see a big “calories burned” number, and still do not see the scale budge. The conclusion turns personal fast: my metabolism is broken, my body is different, none of this works.
The explanation is usually less dramatic than people expect. It’s an accounting problem. The inputs are estimated, the outputs are noisy, and the gap between what you think you burned and hat you actually ate gets filled with wishful math.
The fix can be as simple as an audit. Keep the tracker. Keep the log. Add a reconciliation step so the numbers work for you instead of against you.
The easiest place to start is with calorie burn. Wearables struggle most with energy expenditure. Research finds consumer devices can be decent at steps and often reasonably close on heart rate, while calorie burn estimates vary widely across brands and activities.
A large systematic review of wrist wearables reported poor accuracy for energy expenditure across devices. The paper is here if you want the details.
So a smart watch is usually best as an estimator. It takes signals like heart rate, motion, and your profile data, then runs them through a model. Models can be directionally helpful while still being wrong in absolute terms. That is why two people can do the same workout, see different burn numbers, and both devices can still be helpful.
Now look at the other side of the ledger. Food logging tends to undercount intake. Portions drift. Oils and sauces go missing. Restaurant entries are guesses. Snacks and gut-feelings like tastes don’t make it into the log. And once a big burn number shows up on your wrist, it becomes very easy to grant yourself extra calories that the spreadsheet never approved.
Then comes compensation. Increase exercise and many people unconsciously reduce other movements. More sitting. Less fidgeting. Fewer steps outside the workout. Total daily burn often rises less than the workout calorie estimate suggests because the rest of the day shifts quietly.
The honest calorie burn story has a boring conclusion: your data needs a reconciliation step.
Build a three-column reality check for two weeks. Let the trend settle arguments.
- Column 1: Intake. Log what you eat as consistently as you can. A calorie tracker spreadsheet in Google Sheets gives you structure from day one.
- Column 2: Burn. Use your watch’s total daily burn if it provides it, or use steps plus workouts as a proxy. Treat this as an estimate, not a permission slip.
- Column 3: Outcome. Track daily scale weight, then focus on the 7 day average.
Now compare what the numbers predict to what happens. If your spreadsheet says you are in a 500-calorie daily deficit, you would expect roughly one pound per week of loss over time. If the 7-day average weight is flat after two weeks, one of the inputs is wrong, the timeline is too short, or both.
In practice, the most common outcomes look like this.
- The watch overestimated burn. Extra food got “earned” on paper. This is a classic stall. Stanford researchers found wrist devices could be fairly close on heart rate while doing a poor job estimating calories burned. That write-up is here.
- The log underestimated intake. The spreadsheet says 1,900, reality lands closer to 2,300, and the gap hides in weekend meals, cooking fats, snacks, and “small bites.”
- Water masked the trend. Hard training, salty meals, poor sleep, and higher carbs can raise water weight. The scale can look stalled while fat loss continues. That is why averages matter.
- Maintenance was different than the calculator. TDEE formulas provide a starting estimate. Your real maintenance is personal. A TDEE calculator spreadsheet can set a baseline, then you adjust based on outcomes.
Once the error is clear, the plan can stay gentle. Most people do best with one controlled lever and one consistent target.
- Control one number. Intake works best because it is easier to standardize than burn.
- Under-credit exercise calories. If you are eating back all your “burn,” stop. Consider counting only a portion, or none, until the trend supports it.
- Use weekly averages. Daily scale changes are noise. The 7-day average shows direction.
- Adjust one variable at a time. If weight is flat for two consistent weeks, reduce intake modestly or add a bit of walking.
If weight loss is your goal, tie everything together in one place. A dedicated weight loss spreadsheet keeps the process trend-focused and reduces the urge to negotiate with your watch day by day.
Wearable data shines at behavior. It nudges you to move, reinforces consistency, and gives you a feedback loop. Food logs shine at awareness. Pair them, reconcile them against the scale trend, and you get a system that corrects itself.
The goal is clarity, then one small adjustment that moves the trend the right way.
If you have a medical condition, a history of disordered eating, or you are considering aggressive calorie restriction, talk with a qualified clinician or dietitian before changing your approach.
