Good article, the studies linked to it describe people who are hyper, and it makes sense being hyperthyroidism could cause muscle breakdown. I don't think in the study it was reported what level of FT3 cause the muscle break downWhile the link below describes in great detail why high thyroid hormone levels may make building muscle more difficult, there are lots of other reasons why you would not want low levels (low energy, etc) and there are other ways to counteract this issue such as eating more, so lowering thyroid for this one reason doesn't seem like a great idea unless you can do so with no other adverse affects.
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Thyroid Hormone Effects on Energy Metabolism and Protein Turnover at a Glance
Thyroid hormones are hormones that are secreted by the thyroid. The thyroid is an endocrine gland in the front of your neck that’s located directly belowthinksteroids.com
Optimal for what?Optimal FT3 should be anywhere around 3.7 to 4.2 or so.
I wanted to see what everyone experience was in regards to building muscle and optimizing thyroid, perhaps hearing some anecdotes from ectomorphs like me.I can assure you that having sub optimal levels will most surely interfere with muscle building. You’re probably seeing posts about how t3 is catabolic etc. Those guys take huge amounts to burn fat. Being within normal range will have zero negative impact on muscle building and only positive.
Predict estradiol, DHT, and free testosterone levels based on total testosterone
This tool provides predictions based on statistical models and should NOT replace professional medical advice. Always consult with your healthcare provider before making any changes to your TRT protocol.
Enter your total testosterone value to see predictions
Results will appear here after calculation
A form of estrogen produced from testosterone. Important for bone health, mood, and libido. Too high can cause side effects; too low can affect well-being.
Dihydrotestosterone is a potent androgen derived from testosterone. Affects hair growth, prostate health, and masculinization effects.
The biologically active form of testosterone not bound to proteins. Directly available for cellular uptake and biological effects.
Lakshman KM, Kaplan B, Travison TG, Basaria S, Knapp PE, Singh AB, LaValley MP, Mazer NA, Bhasin S. The effects of injected testosterone dose and age on the conversion of testosterone to estradiol and dihydrotestosterone in young and older men. J Clin Endocrinol Metab. 2010 Aug;95(8):3955-64.
DOI: 10.1210/jc.2010-0102 | PMID: 20534765 | PMCID: PMC2913038