After feeling constantly tired/exhausted for what seems like years and losing interest in everything (plus various other things), I decided to go to the doctors a couple of months ago. I gave a blood sample and three days later I got a phonecall saying I had an underactive thyroid. I was relieved to hear it was treatable and I started on 100mcg of Levothyroxine straight away.

Just over a week ago I had my second blood test. My TSH level had dropped from 156 in the first test, to 56 in the second test. As a result my medication was upped to 150mcg.

Now, my question is, as a 25 year old male I regularly play football and go to the gym. However for the 8 weeks between my first blood test and my second, I did not play football or go to the gym to see if I could feel any difference in how I felt (my muscles had started to burn and hurt when running). So, if I do exercise, will this make my body use more thyroxine, thus meaning the result of the level of TSH in the blood test may be different if I exercised? I don't want to not exercise and receive the right level of Levothyroxine, then begin exercising again - meaning I might go tired again and may actually need more thyroxine because my body will need more to compensate for the usual amount of sport I play.

I hope you can understand the question..

I really can't wait to feel normal! Not being tired and wanting to sleep all the time, being interested in things like I used to be. And I hope my memory returns also!