You can set upper and lower limit vibration alerts on the Frontier X to the heart rate zones just like other users since these thresholds can be customised to a single heartbeat. A good rule of thumb to follow if you know the difference between your resting heart rate before and after your beta-blocker would be to customise your heart rate threshold for the zone you want to work in, by subtracting the difference between your resting heart rates. We are working on tools that will create more custom features for individuals like yourself in the future. Remember to check with your doctor prior to beginning an exercise program to make sure your heart can keep up with what you have planned.