Activity math explainer
How NectariaFit Calculates Activity Calories
See which activity details the AI interprets, which calculations remain deterministic, and why activity calories are still approximate.
Published by NectariaFit · Updated
Language interpretation and calorie math are separate jobs
When you write “walked 5 km in about an hour,” the assistant can identify the activity, distance, duration, and source wording. That is interpretation. NectariaFit does not let the model invent the authoritative calorie value that is stored beside the activity.
The backend maps the interpreted activity to a configured activity type, applies bounded correction rules, and calculates the result from validated inputs. The model proposes the structured action; application code owns the calculation and database write.
Distance and profile weight drive the current calculation
The current activity calculation uses corrected distance, a configured calories-per-kilometre baseline for the activity type, and the profile weight relative to the reference weight. The final value is rounded by deterministic application code.
Duration can help describe the session, but distance is required by the current calculation. If a message describes movement without enough measurable detail, NectariaFit can acknowledge it without adding unsupported activity calories.
Personal rules are bounded and visible
People may need repeatable adjustments—for example, ignoring a particular activity source, scaling a distance, or supplying a personal calories-per-kilometre rate. NectariaFit supports a small set of validated rule types. A conversational suggestion does not become an active rule until the user reviews and confirms it.
Rules are structured data rather than executable prose. This keeps the same input reproducible and prevents an old chat sentence from becoming hidden calculation logic.
Why the result is still approximate
A deterministic formula can be consistent without being a direct measurement of human energy expenditure. Terrain, pace, efficiency, fitness, carried weight, equipment, and sensor error can all affect the real value. Profile weight and a distance category do not capture every individual variable.
For that reason, activity calories are best interpreted as a transparent wellness estimate. NectariaFit keeps the input and correction visible so you can understand where the number came from.
How activity affects the day view
Daily outflow combines a routine baseline derived from the profile with calories from logged deliberate activity. The routine level is intended for ordinary non-exercise movement, while walks, runs, and workouts are logged separately to reduce double counting.
Day, week, and month views are derived from the underlying records. Editing a historical activity changes later summaries automatically; it does not require the assistant to rewrite a cached total.