Two early rehabilitation training models in male patients after coronary artery bypass surgery: application of continuous walking training as an alternative to interval cycle ergometer training

Introduction
Walking training is a good alternative to the commonly used cycle ergometer training. It is still necessary to develop rehabilitation programs based on walking characterized by a high degree of safety and effectiveness. Application of continuous walking training as an alternative to interval cycle ergometer training in men after coronary artery bypass graft (CABG) surgery, using the 6-minute walk test (6-MWT) to determine the initial training load.

Material and methods
Forty-four men aged 45 to 76 years, up to 3 months after CABG surgery, were randomly assigned to continuous training on a treadmill (study group) or interval training on a cycle ergometer (control group), performed 6 times per week (12–15 sessions). Participants underwent the treadmill exercise stress test (TEST) and 6-MWT at the begining and after completion of the rehabilitation program. Before and 3 minutes after the 6th and 12th training session blood lactate concentration was determined.

Results
Energy expenditure in TEST increased from 4.4 to 6.3 MET in the study group and from 5.0 to 6.5 MET in the control group. Distance walked in 6-MWT increased from 420 to 519 m and from 438 to 510 m, respectively. Resting heart rate (HR) and double product (DP) decreased only in the study group as well as systolic blood pressure (SBP), HR and DP at peak exercise load in baseline TEST. Mean energy expenditure during training sessions was 2.6 MET in the study group and 2.8 MET in the control group (NS). Exercise blood lactate concentration did not exceed 2.0 mmol/l in both groups.

Conclusions
Both rehabilitation programs were of similar effectiveness and their intensity did not exceed the anaerobic threshold.