Exercise is necessary for healthy living, yet individuals with intellectual disability (ID) remain strikingly inactive compared with nondisabled peers. To improve this outcome, individuals with ID can exercise independently by self-instructing. Self-instruction is considered a pivotal skill once it generalizes to untrained stimuli. This study used a multiple probe across participants design to simultaneously evaluate the effects of progressive time delay (PTD) on the acquisition of self-instructional behaviors to perform exercise routines and the generalization of these behaviors for four U.S. elementary students with ID. Generalization was programmed by implementing PTD procedures with two different workout schedules while simultaneously and continuously probing two other workout schedules until mastery. Three of the four participants acquired self-instructional behaviors with their target schedules and generalized these behaviors to two novel schedules resulting in independent performance of 36 untrained exercise behaviors. Results and discussions pertaining to generalization evaluation within single-case designs are described.