For most of history the period after an illness broke was treated as a separate stage with its own regime. Convalescence had rules, and much of the institutional support for it came from religious communities.
Recovery was a defined phase, not an absence of illness
Older medical writing distinguishes sharply between the crisis of a disease and the long return afterwards.
The second phase had its own prescriptions covering food, sleep, air and exertion, and physicians expected relapse if the transition was rushed.
Modern usage has largely lost the word, and with it the assumption that returning to ordinary activity is a graded process rather than a single moment.
Diet carried most of the therapeutic weight
Where few effective remedies existed, regulating what a recovering person ate was among the interventions a caregiver could actually control.
Preparations moved by stages from liquids through soft foods to ordinary meals, and the sequencing was described in considerable detail.
Much of this knowledge sat with household and monastic cooks rather than physicians, and survived in recipe collections rather than medical texts.
Religious houses supplied the buildings and the labour
Sustained nursing requires people who are free to provide it, and monasteries and similar institutions had populations organised around obligation rather than wages.
Infirmaries within these houses served members first and often extended to travellers and the poor, with the duty framed as a religious one.
Rules for such communities set out how long a sick member might be excused from the ordinary schedule, which gave convalescence formal protection.
Time and place were prescribed deliberately
Guidance frequently specified where a recovering person should be placed, favouring light, moving air and separation from the ordinary noise and traffic of a household.
Quiet was not only comfort. It reflected a view that mental agitation delayed recovery, so visitors and news were regulated alongside food.
Where a change of location was possible, spa towns and rural retreats absorbed convalescents in numbers, which is how many of them grew.
The category faded as acute care improved
Shorter illnesses and effective treatments reduced the length of the recovery phase for many conditions, and hospital economics came to favour early discharge over extended stays.
The specialised institutions that once handled the stage largely disappeared or were converted to other uses, leaving the work to households that no longer had a shared vocabulary for it.
Anyone recovering from serious illness should follow the guidance of their own clinicians, but the older framing remains a reminder that the end of an illness and a return to full activity are not the same event.