Comparing the Effect of Eight Weeks of High-Intensity Interval Training and Moderate-Intensity Continuous Training on Physiological Variables of Exercise Stress Test in Cardiac Patient after Coronary Artery Bypass Graft

Cardiac rehabilitation improves functional capacity in cardiac patients after coronary artery bypass. The aim of this study was to compare the eight weeks of interval training with continuous training on stress test physiological variables in patient with cardiac diseases after coronary artery bypass graft (CABG) surgery.

In this clinical trial study، 30 patient with cardiac diseases in Tehran Heart Center (Iran) having had CABG surgery were randomly divided into two groups، high-intensity interval and continuous moderate-intensity training (program common). The program of interval group was included 4 repeats × 4 minutes at 90-95% peak of heart rate (HR) and continuous group، 60-80 minute at 70-85% peak HR، three sessions per week for 8 weeks. Functional capacity (VO2 peak)، distance traveled، time to exhaustion and maximum heart rate (HRmax) were assessed during the Bruce exercise stress test before and after the training program. The collected data were analyzed using the one-way analysis of variances (ANOVA) and post hoc Fisher''s least significant difference (LSD) tests.

Functional capacity was increased significantly following the both of training programs with no significant difference between the two groups (P < 0. 05). The increases in traveled distance، time to exhaustion، and HRmax after interval program were more in interval program group (P < 0. 05).

It seems that both high-intensity interval and moderate-intensity continuous training improve functional capacity in cardiac patient with cardiac diseases after coronary artery bypass sugery. However، interval training was more beneficial than continuous training in some parameters such as traveled distance، time to exhaustion، and HRmax during exercise stress test.