Track daily sedentary time.
Sedentary time is best judged against waking hours rather than the whole day, since sleep is not sitting. Adding work and leisure sitting gives the total, and expressing it as a share of waking hours is what makes it comparable between a shift worker and an office worker. One movement break per sedentary hour is the common practical target, and the shortfall shows how far the current routine falls from it.
Sedentary share
Waking hours = 24 - sleep hours; sedentary share = (work sitting + leisure sitting) / waking hours x 100; breaks needed = one per sedentary hour
Sedentary behaviour is one of many factors affecting health outcomes. This tool provides a general estimate and is not medical advice — discuss individual risk with a healthcare professional.
Risk rises progressively with total sitting time and is worst when it is accumulated in long unbroken blocks. Above roughly 8-10 hours a day, breaking up the sitting matters as much as total exercise.
It reduces the risk substantially but does not eliminate it. Prolonged uninterrupted sitting has effects independent of whether you also train.
Two to three minutes of standing and walking, ideally every hour. Short frequent breaks appear more effective than a single long one.