This is a high risk client. Beta blockers will decrease both heart rate and blood pressure, like Joanne said. Using the Rating of Perceived Exertion chart is a great way to get a good idea of how hard the client is working. The trainer working with this client should require a physician’s approval and should request that that physician provide the client with set guidelines for his exercise program so that he can share that information with the trainer.
As an example of how the beta blocker will affect exercise, since the medication lowers heart rate, this client’s resting heart rate may be lowered, on average, by 20 beats per minute. Consider this when measuring his heart rate for purposes of calculating target heart rate. Just because his heart rate isn’t in the ideal range of what you would expect, consider the overall change that has occurred as far as stress on the cardiovascular system. Consider using the Karvonen Method for calculating Target Heart Rate.