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Medical Why stress is bad for the heart

  1. Dec 4, 2012 #1


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    why stress is "bad" for the heart

    Hi. I don't understand why stress is "bad" for the heart while exercising is "good". For example I'm having a final exam tomorrow worth 100% of my grade for a course and I'm having a huge stress (I feel adrenaline rushes almost permanently). I'm also used to run 10 km twice a week and so I know how painful running is (extremely painful). In both cases the heart beats much faster than when at rest, but I don't understand why stress would be different from say running, for the heart.
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  3. Dec 4, 2012 #2
    Re: Stress, heart

    You might find "Why Zebras Don't Get Ulcers", by Robert Sapolsky a good read. It is a really well written, not super technical, treatment of stress and its relation to diseases.

    Its been a few years since I have read it so I am fairly hazy on the details but the big take-away is basically that you are correct. Stress is stress whether it comes from exercising or freaking over an exam. The difference between the two is that the former is a very acute condition (IE you exercise for an hour a few times a week) while the latter tends to be chronic (stressing for a couple of weeks straight around exam-time). It is the condition of chronic stress and the accompanying metabolic/hormonal cascades which lead to the detriment of health in the long term. Basically it reinforces the idea that too much of anything is a bad thing.

    Again, if you are very interested you should check out the book.
  4. Dec 4, 2012 #3


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    Re: Stress, heart

    First of all thanks for the book suggestion.
    Actually I'm very confident that exercising in the gym or running is much, much more stressful for the heart than freacking out for an exam. Keeping a running rythm for 40 minutes at your maximum capacity is extremely painful and the heart is working much harder than when one has a mental stress. In fact I do not know if it's possible for the heart to work even harder without breaking itself. And it's well known that exercising a few times a week is good for the heart.
    I am guessing the difference really comes to what you mentioned: the hormonal cascades. I wonder which hormones that pop ups when we're stressed are "bad" when applied for a long time and repeatedly over days.
  5. Dec 4, 2012 #4
  6. Dec 4, 2012 #5
    Re: why stress is "bad" for the heart

    I'm no expert on the physiology of stress myself. I've jus done a bit of reading on the subject.

    You are both correct, there are differences between exercising strenuously for an hour a few times a week and constantly worrying about exams, bills, career etc.

    The point is that there are also many similarities IE sympathetic nervous system tone/fight or flight etc.

    The HUGE difference between the two situations is the frequency and duration of the stress. In essence, constantly freaking out about things doesn't allow ones body to 'calm down'. Meaning there is a constant amount of low intensity 'fight or flight' going on. It's not necessarily about the magnitude of the stress response at any given time point because them exercise would be horrible for you. It's more like an area under the curve type of deal. Exercise gives a lot of stress in a relatively short amount of time with a good amount of recovery time to allow for adaptation whereas finals leave one in a state of low level stress for very long periods of time.

    You can also look up Selye's GAS model/principle for further reading.
  7. Dec 9, 2012 #6
    Re: why stress is "bad" for the heart

    I'm stressing out from reading the list of warning signs - I seem to have about 95% of them :bugeye:
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