Purpose The purpose of this trial was to compare the effectiveness of standardized outpatient cardiac rehabilitation combined with treadmill power walking versus standardized outpatient cardiac rehabilitation alone on health‐related quality of life (HQoL), functional exercise capacity (FEC), left ventricular ejection fraction (LVEF) and metabolic equivalent of tasks (METs) in patients who went post coronary angioplasty (CA). Further this study evaluated the association between average numbers of steps taken with above clinical outcomes. Methods In a pragmatic sequential randomized clinical trial, 24 patients were randomized into two groups (n = 12) and participated in a standardized outpatient cardiac rehabilitation program (SOCRP) with treadmill power walking as an intervention group and SOCRP alone in control group. Scores obtained before and after 4 weeks of intervention, that is, after 12 treatment sessions were assessed using a HQoL questionnaire and 6‐min walk test (6 MWT). Average number of steps taken throughout the 4 weeks, METs and LVEF values were obtained by pedometer, exercise stress testing and echocardiogram respectively. Results Significant improvements were found in intergroup and intragroup comparison after 4 weeks of cardiac rehabilitation (p < 0.05). Scores of 6 MWT and LVEF significantly improved in the intervention group (p < 0.003) compared to the control group (p < 0.032). HQoL components that is, global and physical, MET values and average number of steps were significantly higher in the intervention group compared to the control group (p < 0.001). Conclusion SOCRP with power walking was more effective in improving HQoL, FEC, LVEF, METs and average numbers of steps than SOCRP alone although both interventions were significant after 4 weeks in patients underwent CA and completed cardiac rehabilitation program. Positive significant associations were found between the average number of steps taken with scores of METs and scores of global and physical domains of HQoL.