This study examined the strategy utilized by patients with cardiovascular disease to regulate exercise intensity using the Rating of Perceived Exertion (RPE) and tested if a step-up procedure would reduce overshoot of target heart rate (HR). Also the study investigated if Prescription Congruence and Intensity Discrimination, components of the Intensity Self-regulation Model, could be validated for these patients. An estimation and production paradigm was used. HR was measured at 2-min. intervals during 6-min. stationary cycle ergometer exercise trials. Data for four experimental trials were compared: (1) a work intensity set by experimenter to achieve a target RPE of 11 (Estimation 11), (2) an intensity set by experimenter to achieve a target RPE of 13 (Estimation 13), (3) an intensity varied by participant every 2 min. to produce a target RPE of 13 (Production 13), and (4) a Step-up Procedure with the intensity varied by participant, first producing a target RPE of 11 during the first 2 min., followed by producing a target RPE of 13 from min. 2 to 6 of exercise (Production 11 + 13). A very small effect size was found for HR between Production 13 and Estimation 13, and a moderate effect size was noted for the increased HR when patients produced a target RPE of 13 as compared to 11. The participants could be divided into 2 groups: 10 patients comprised a Higher group whose HR at 2 min. during Production 13 was greater than HR at 2 min. during Estimation 13, and 6 patients in a Lower group with HR at 2 min. during Production 13 less than or equal to HR during Estimation 13. A large effect size was found at 6 min. for the reductions of the Higher group's HR overshoot and for the Lower group's HR undershoot during Production 13. All participants in the Higher group (n=10) had a clinically significant HR overshoot of 5 beats x min.(-1) at 2 min. during Production 13. Using a Step-up Procedure (Production 11 + 13), a large effect size was found for the reduced number of patients (n=3) with an overshoot of 5 beats x min.(-1) at 2 min. This supports the ability of participants in cardiac rehabilitation programs to meet the Prescription Congruence and Intensity Discrimination components of the Intensity Self-regulation Model in the RPE 11-13 zone. Evidence was found for overshoot/undershoot of target HR at 2 min., supporting a proposed third component, Production Strategy, of the Intensity Self-regulation Model. The 2-min. Step-up Procedure reduced some patients' tendency to "overshoot" target intensity.

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