A method for transmitting successive messages forming a frame in a telecommunication system with M sources (s1, . . . , sM), L relays and a destination, M>1, L≥1 according to an orthogonal multiple-access scheme of the channel between the M sources and the L relays with a maximum number of M+Tmax time slots per transmitted frame including M slots and Tmax cooperative transmission slots. The method includes: a slow type link adaptation determining an initial rate for each source by destination based on an average SNR of each link and transmitting to each source the initial rate; and for each frame out of several, successively transmitting the messages of the M sources during the M slots phase with, respectively, modulation and coding schemes determined from the initial rates. The link adaptation maximizes the aggregate rate of all the sources subject to the constraint of a target average BLER εcom after Tmax≥X≥1 cooperative transmissions.