More troubling is that I just began a cardiac rehab program, and did a treadmill workout at a speed/incline/duration (30 minutes) that I have been doing for years - so I know what my response should be. Normally, my heart rate would be around 130-135, and the
coreg (presumably) kept it down around 115-120. I felt fine, and was encouraged - but afterwards, I felt extremely fatigued for the rest of the day, and had a great deal of soreness in my legs.