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    What causes heart rate to drop during exercise?
    An_193111 posted:
    During 20 minutes on the treadmill, I checked my heart rate periodically. Shortly after I started, it was 72. The next time I checked, it was 68. I was just warming up, and I had it set to the lowest speed, so I sped it up slightly. When I checked again, it was back up to 72, so I figured things were okay. I continued to gradually step up the pace, but was never at any time feeling over-exerted. I didn't check my heart rate again until I'd been on it for nearly 20 minutes. That's when I discovered my heart rate had dropped to 42. Thinking the monitor must be wrong, I tried it again, and got the same result. I started slowing down the pace to cool-down, and checked it again...this time it was 40, so I stopped and got off of the treadmill. I was feeling a little light-headed, but that could've just as easily been due to the fact that I hadn't eaten, and after resting for about 10 minutes, I felt fine. What's the deal? Can that heart rate of 42 possibly be right? I am in my late 50's, and had some issues with low blood pressure a few years ago. I went through a full panel of testing for heart problems, and everything checked out okay.
    toneman84084 responded:
    Did you try taking your pulse yourself? I know that I can't trust the equipment at the fitness center, it's usually off by some amount depending on the equipment. I always take it manually and verify the machine.

    Just a thought.
    CardiostarUSA1 responded:

    "....and had some issues with low blood pressure a few years ago. I went through a full panel of testing for heart problems, and everything checked out okay."

    Things may/can change at any time, even in a split-second.

    "What's the deal? Can that heart rate of 42 possibly be right?"

    It may/could be.

    In general-only here, during vigorous exercise/physical activity, one's heart/pulse rate and blood pressure (BP) should rise accordingly, though in some, heart rate and/or blood pressure may drop, which may/can be indicative of a problem, thus requiring a thorough investigation by a qualified doctor or doctors.

    As reported, causes of a drop in heart/pulse and/or blood pressure during vigorous exercise (exercise-induced decrease) includes, but is not limited to, problems in the coronary arteries (e.g., atherosclerosis, arteriosclerosis), the heart muscle/myocardium (e.g., damage or dysfunction), and the heart valves (e.g., regurgitation/leakage or stenosis/narrowing).

    Normal resting range heart/pulse rate is 60-100 beats per minute (BPM). Average resting heart/pulse rate in men is 72-78 BPM and in women is 78-84 BPM. Under 60 BPM is bradycardia (slow heartbeat). Bradycardia may/can cause various symptoms such as lightheadedness or dizziness, confusion, weakness, or syncope (includes passing out and fainting).

    be proactive in your health care and treatment. Most important, communicate/interact well with your doctors. Best of luck down the road of life.

    Take care,


    WebMD member (since 8/99)



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