Thyroid medication use as an assisted bodybuilder should be approached with caution and based strictly on individual neednot just because it's what you do during prep. Too often, both competitors and non competitors L carnitine reduces hyperthyroidism symptoms l Carnitine Supplementation in Recovery after Exercise There are 3 main types of thyroid medications available T4 T3 (usually combined with T4) NDT desiccated thyroid (a combination of T4 + T3) Most are widely available L Carnitine in Drosophila: A Review Didn't another study show carnitine was good for the heart?