Q: I am a 71 year old male with a resting heart rate of about 57. It goes up to about 100 when standing, 140 walking if I run up to 175. Also they change rapidly and sometimes my monitor reads zero. Are theses rates dangerous?
A: With a rate of zero, you should be dead. Zero is a dangerous rate. I have to wonder if your monitor is functioning properly. It is normal for your heart rate to increase with activity. It would be smart to discuss with your doctor if you need to take any precautions with exercise.