Quote Originally Posted by maillotpois
(Wow, he has the same thyroid disease I have! I can assure you his thyroid meds are not performance enhancing... )
Not entirely true. Cytomel (T3) is a very popular drug among body builders and other athletes who need a super-low body fat percentage to perform at the top of their game (hmmmm.....sound like cyclists?). You can buy it on the web (along with other anabolic steroids) and there are hundreds of articles out there that explain dosing and phasing for weight loss. Down-side is that excess T3 can damage your heart and you can also lose muscle mass.

Levoxyl/Synthroid/et al (T4) is not popular because it takes a long time to dose into your system and the nuances of proper dosing are so tricky.

BTW, after spending years in hypo hell, I definitely think thyroid meds are performance enhancing (in a different sense). When I was super-hypo, I didn't recover, suffered severe muscle and joint pain, had a compromised immune system, the list goes on and on. All of these symptoms affected my ability to race my bike. By correcting this, my personal performance was definitely enhanced.