What is Your Blood Telling You?

In my column this month at Endurance Corner, I write about laboratory (blood) tests that may be useful for athletes. I’m frequently asked which tests are useful and also how to interpret the results of the various tests. I provide some recommendations about how to work with your physician to decide when laboratory testing may be useful for you….in your particular circumstance.
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  1. says

    Hey Dr. Creswell,
    There’s a lot of spam in the comments here but I wanted to let you know there’s at least one reader who appreciates your efforts.
    Thanks from a long-retired competitive cyclist.


    PS, would love to hear about the effects of Metoprolol on vigorous exercise.

  2. says


    Good to hear from you. And sorry about the spam! Glad that you found the blog….and glad to hear that you’re a (retired) cyclist.

    Metoprolol is one of the beta-blockers, a medication designed to slow the heart rate and lower the blood pressure.

    It’s not often a good choice for athletes because it:

    1) limits the heart rate, so it will limit your high-end activities and

    2) reduces the strength with which the heart contracts with each heartbeat. It will reduce the maximum blood flow that your heart can generate.

    Metoprolol or other beta-blockers may not have a noticeable effect if you only pursue low-intensity sporting activities such as golf, etc.

    Hope that helps.


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