Starting running and hypothyroidism

It would seem that there may be a link between endurance running and hypothyroidism (not necessarily causal, though). I've recently started running for the first time and my thyroid function has declined; it may be coincidence. I definitely wouldn't class myself as an endurance runner as I'm only just able to keep going for 28 mins without stopping (thanks, c25k!). Has anyone else had a similar experience? Was it temporary or did you need to adjust the dose of whatever medication you're on for the long term?

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  • hose, I don't think it is a coincidence. I've read several articles about the negative consequences of endurance training and many athletes causing their own hypothyroidism. It may also be the reason that you can buy T3 over the counter for this very purpose. Dr. Mercola has been the source for some of them.

  • But would sub-30 mins really be counted as 'endurance'? I guess it doesn't really matter since I've discovered that I love running and I'm going to keep doing it. I've been hypothyroid for nearly 20 years, so there can't be much life left in the old gland now (hint, hint, gland: give up the ghost already!)

  • Increased activity can make you feel that you're running out of steam. I had to raise my medication for this reason in April.

  • That's interesting, because up until Nov last year I had run for 4 years. The first year or two were great, but the following two years (esp the last year) just became more and more difficult until I had no choice but to stop. I didn't know I had a thyroid problem then, and have only just started NDT. It was in fact the running that alerted me to the thyroid issue really as I went from running to barely being able to walk up hills!

  • I run a lot and it makes me feel better! I've just had my dose reduced from 75mcg to 50mcg as my TSH had dropped to 0.09, so I don't think it necessarily follows that it would negatively affect your thyroid (I personally think it's coincidence / other changes such as healthier diet that have changed things for me though). Glad you're enjoying it and well done for doing the C25k!

  • Just make sure that you actually feel okay with the dosage decrease; don't let your GP be a slave to the numbers. The free T4 result is the most important one and you may want to be nearer to the top end of the range. (My optimal results are TSH 0.05, fT4 19, and my GP is happy with this because anything less and I feel crappy.)

  • Thanks for the input, I am keeping a close eye on how I feel as I really don't want to go hypo again! But I've been having palpitations, chest pains and insomnia so I'm trying a lower dose to see how I go. FT4 was 19. If I feel worse I'll put my dose back up, my GP is reasonably good so I think he'll be ok with that.

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