Only what you enter, plus what is needed to sign you in:
- Your email address and a securely hashed password.
- Profile details you choose to add: display name, height, date of birth, sex, and activity level. These exist solely to calculate your calorie and macro targets, and every one of them is optional.
- Bodyweight entries, goal weight, and any notes you attach.
- Workouts: sessions, exercises, sets, reps, load, RPE, and templates.
- Nutrition: your food library, saved meals, and your daily food log.
Some of this is information about your body and your eating. It is treated as private by default: every row is readable only by the account that created it, enforced by the database itself rather than by application code.