The relative effects of preadmission self-instructional information on levels of performance and time needed to achieve level of mastery of exercise behaviors were examined using a sample of 130 presurgical cholecystectomy and herniorrhaphy patients. Experimental interventions were (1) no preadmission information, (2) specific preadmission instructions, and (3) nonspecific preadmission instructions. Preadmission instructions consisting of either a specific or nonspecific booklet mailed to patients focused on techniques for coughing, deep breathing exercises, leg movements, and ambulatory behaviors. During hospitalization, patients' exercise behaviors and the length of teaching time required for patients to perform the exercise steps were measured. Findings showed that subjects in the specific exercise instruction group performed significantly more of the exercise behaviors common to both booklets than subjects in the nonspecific exercise instruction group. Subjects in the specific instruction group also performed significantly more of the behaviors available to them than the nonspecific instruction group. Required postadmission teaching time did not differ significantly between the specific and nonspecific information groups, but both the groups required significantly less teaching time in the hospital than the no-preadmission instruction group.