| The purpose of this study was to evaluate the relative effectiveness and efficiency of forward chaining, reverse chaining and total task presentation in the acquisition of three targeted motor fitness skills with individuals diagnosed as severely mentally retarded. The modified sit and reach, modified supine tuck and modified squat thrust were task analyzed into seven subtasks each.;The subjects were then given four baseline trials in which the skill was demonstrated and a verbal command was given. Following baseline trials the subjects were instructed over 12 sessions in each of the motor fitness skills using the designated instructional strategies and a system of least intrusive prompts and systematic reinforcement. During each instructional session six learning trials were conducted on each motor fitness skill. The order of presentation of the skills was counterbalanced over the instructional sessions. Two weeks after the instructional sessions ended, four retention trials were conducted identical to the baseline trials.;An alternating treatments single-subject design was employed. Individual and group data were analyzed utilizing both visual analysis and descriptive statistical methods. Additionally, acceptable measurements were reported relative to content validity, social validity, reliability and procedural integrity.;Based on the data obtained, there was no significant difference between forward chaining, reverse chaining and total task presentation in the celeration, number of trials, time and amount of prompting required to reach criterion on three targeted motor fitness skills. Further, there was no significant difference between the three instructional techniques in the retention of three targeted motor fitness skills.;After a screening procedure, six individuals from a midwestern school were selected and divided into two age groups. The subjects were then randomly selected to receive instruction in each of the motor fitness skills, each paired with one of the instructional strategies. The mixture of instructional strategies and motor fitness tasks was counterbalanced throughout the study.;The results of this study suggest several implications and avenues for future research regarding motor fitness skill acquisition by youngsters diagnosed as having severe mental retardation. These are discussed relative to task type, task analyses, individual differences, reinforcement density, instructional timing and prompting strategy. |
