Abstract: A mattress for recumbent prophylaxis, which has a plurality of support elements in sequence relative to one another, with each support element having at least two air-inflatable double chambers or inflatable members connected together by a fillet. Each double chamber or inflatable member has a bottom hollow body connected to an opposite, top hollow body by a common partition wall with at least one opening. The support elements are detachably connectable with one another and are arranged transverse to the longitudinal axis of the mattress. Each of the bottom hollow bodies are connectable by a short connecting piece through hose connections to an air pump assembly in such a manner that the different chamber systems which are not communicating with one another can be acted upon with air alternately.