'exercise' originates from Latin, specifically the word 'exercitium', where 'ex-' meant 'out' and 'arcere' meant 'to keep or hold'.

'exercitium' transformed into the Old French word 'exercice', and eventually became the modern English word 'exercise' through Middle English.

Initially, it meant 'to keep busy or occupied', but over time it evolved into its current meaning of 'physical activity to improve health'.