Hemodynamic Responses to Resistance Exercise in Patients With CAD
What are the hemodynamic responses to resistance exercise with moderate load (international guidelines) versus resistance exercise with high load in patients with stable coronary artery disease (CAD)?
Fifteen revascularized patients with CAD with moderately good ventricular function engaged in 2 different bouts of resistance exercise: 3 sets each of 15 repetitions max and 4 repetitions max. The resistance exercise protocols were performed in a randomized, crossover design on separate days 48 hours apart. Measurements of systolic and diastolic blood pressure (BP), heart rate (HR), stroke volume, cardiac output (CO), and systemic vascular resistance (SVR) were monitored pre-exercise and continuously during exercise.
Systolic and diastolic BP pressure increased significantly more with medium-load resistance exercise than with high-load and were significantly higher with longer duration (15 repetitions max) than shorter duration (4 repetitions max). Elevations in BP were explained by moderate increases CO primarily due to elevations in HR; SVR decreased in both resistance exercise protocols. Both protocols were well-tolerated, though participants preferred the high-load/low-repetition to the medium-load/high-repetition resistance exercise.
In patients with stable CAD, high-load/low-repetition resistance exercise causes less BP elevation than medium-load/high-repetition resistance exercise and is otherwise well-tolerated and preferred by the participants. Thus, it is prudent in this high-risk population to recommend high-load/low-repetition resistance exercise and to increase load before increasing repetitions as resistance exercise progresses, particularly in patients with CAD for whom BP is a concern.
Patients with CAD are likely to experience loss of skeletal muscle mass and strength, which adversely affects overall health and independent living. Therefore, the trend is to add resistance exercise to cardiac rehabilitation, though American Heart Association and other international guidelines endorse low-to-medium load/medium-to-high repetition resistance exercise for these patients. This study suggests, however, that high-load/low-repetition resistance exercise is well-tolerated in patients with CAD and results in a significantly lower BP than low-load/high-repetition resistance exercise. Therefore, increasing load before number of repetitions (duration) is advisable if BP is a concern.
< Back to Listings