The phrase "designated period" refers to a specific, set amount of time that has been chosen or assigned for a particular purpose or activity. Full definition
However, it is crucial to note that the statute does not designate a period of time. (traffictickets.com)
During designated periods, even some periods of high work demand, employees were required to take time off. (sciencemag.org)
This means that we have to have designated periods where you are actively focusing on not losing weight or stressing about it (read more here about the importance of maintenance). (renaissanceperiodization.com)