Last updated October 22, 2026
Vitalis gives you numbers about your own body and training. Numbers feel authoritative, so it is worth being explicit about what they are — and what they are not.
Vitalis does not diagnose, treat or prevent any condition. It is a self-tracking tool. No output from this app — report, plan, chart or assistant reply — constitutes medical advice, and none of it creates a doctor-patient relationship.
We cannot see your full medical picture, and the app does not try to. It knows only what you enter, and it cannot tell whether what you entered is complete or accurate.
Please consult a doctor or registered dietitian before acting on anything here if:
Stop exercising and seek medical help if you experience chest pain or pressure, fainting, unusual shortness of breath, or a heartbeat that feels wrong.
If you think you are having a medical emergency, call emergency services. Do not wait, and do not use this app.
Every derived value in Vitalis comes from a published formula. Those formulas are estimates for populations, not measurements of individuals.
Typical individual error around 10%. It underestimates in people with very high muscle mass — muscle burns more than the equation assumes — and overestimates in people with very high body fat, because fat is treated as if it were partly lean tissue.
The activity factor is a coarse bucket with five levels. Two people who both choose 'moderate' can differ by several hundred calories, because the factor cannot see how much you actually move. Most people overestimate their level.
Estimated from BMI, age and sex — it never measures fat directly. An error of five percentage points is common, and it is systematically wrong for very muscular people and for older adults.
Day-to-day change is mostly water, glycogen and food residue. A swing of one or two kilograms between consecutive mornings is common and usually reflects those factors rather than fat — but it is not always harmless. If weight moves sharply and you cannot explain it, treat that as a reason to check with a doctor rather than as noise. Read the seven-day average; do not judge fat change from a single morning.
This is why the app shows trends and ranges rather than single authoritative figures, and why — once you have a few weeks of consistent data — it shows an adaptive estimate back-calculated from what you actually ate and how your weight actually moved, alongside the formula value.
Reports, training plans, nutrition plans and assistant replies are produced by a language model. Language models can state things confidently and be wrong. They can misread context, over-generalise, or produce a plan that does not suit your situation.
They are also non-deterministic — the same question can produce a different answer tomorrow. Treat AI output as a well-informed first draft from someone who has seen your numbers but has never met you.
Training — particularly with free weights, at high intensity, or after a long break — carries a risk of injury. You are responsible for choosing loads and volumes you can handle, for using correct technique, and for stopping when something hurts. A plan generated by this app is not a guarantee of safety, and it does not know your movement quality.
Missing days, estimated portions, unweighed food and inconsistent weighing conditions all distort the analysis. The app flags gaps where it can, but it cannot know what you did not record.
If your numbers look wrong, check the inputs before concluding the app is broken. Consistent conditions matter more than precision: same time of day, same scale, same state.
Tracking is a tool, not a virtue. For some people it creates clarity; for others it feeds anxiety or disordered eating. If logging your weight or food is making you feel worse, that is a real signal and worth acting on — talk to a professional, and consider not tracking for a while. The app will still be here.
This document is provided in English. Any translation is for convenience only; the English version prevails.