The noted positive physiological effects of reasonable dosages of thyroid hormones included-
*increased protein synthesis rate
*increased rat of fat oxidation
*increased sensitivity of receptors for androgens,slin,gh.IGF1,PGE1,PGF2,clen,ephedrine,cr eatine
*increased metabolization of protein,carbs,fats,and micronutrients.
*increased metabolic rate and calories expenditure
*enhanced oxygen consumption by most tissues
*improved recovery time

noted negitive sides
*loss in lean muscle mass
*increased heart rate
*insomnia
*diarrhea
*vomiting

Thyroid hormones govern the body's metabolic rate. This means that the metabolismof nutrients and subsequent cellular utilization or storage rate is dependant upon blood circulatory thyroid hormone levels. Higher levels result in elevated over all metabolic rate providing that other metabolic factors are accommodated also.

THYROID HORMONES AND CALORIE EXPENDITURE

Those who are familiar with, or have read the section DNP are aware of the term "oxidative phosphorylation". This is a process by which cells/mitochondria convert ADP (Adenosine Diphosphate) into ATP (Adenosine Triphosphate). Basically this means adding another phosphate molecule to ADP so that it can be converted back into the body's energy/ ATP. But the term keeps kids flunking biology anyway. DNP makes cells waste calories and burn fat by "uncoupling" the oxidative phophorylation process and making ti less efficient, even when at rest.

Thyroid hormones are powerful uncouplers of oxidative phophorylation. However this is a different method of action than that induced by DNP. thyroid hormones increase cell/mitochondrial substrate oxidation by effecting both cytochrome-C reducers and cytochrome-C oxidizers. This increases metabolic rate and substrate (nutrient/food) use as fuel for either ATP or heat production . Heat production by a cell is referred to as thermalgenesis, in this casse the conversion of fat into heat. Though other substrates such as glucose/ glycogen can be used for heat production also under adverse conditions.

THYROID HORMINES AND FAT OXIDATION

Fat oxidation or thermalgenesis involves the conversion of fat calories into heat. In the case of thermalgesis caused by thyroid hormones it is due to "special uncoupling proteins" found in fat, muscle and organs called UCP-3. Two things before we continue here. first UCP-3 stands for uncoupling protein -3 (big deal) and special refers to specific not special like the weirdo we all dated once and tried to expalin later. When UCP-3 is increased the calorie expenditure through thermalgenesis increases. But decreases will result in an increase in fat stores. As example, supraphysiological T-3 levels increase UCP-3 600% and below normal levels results in a 300%decrease. this is ehy calorie restricted diets significantlly decrease in results after 2-4 weeks. the body down-regulates thyroid hormone production to save calories and reduce calorie expenditure as heat . the result is less UCP-3 and slower metabolism.
Thermalgenesis and oxidative phosphorylation ncoupling is the reason ahtletes used synthetic thyroid hormnes during calorie restricted or diet phases. The individuals were able to ingest more calories than normal while still burning fat. It should be noted that a minimum of 2 grams of protein per pound of body weight was ingested daily during exogenous thyroid hormone use to prevent excessive muscle catabolism or loss. Athletes commonly stacked adrenalgenic beta-agonist drugs like Clenbuterol,Ephedrine/Norephedrine, or Fenoterol to increase UCP-3 levels and act synergistically with thyroid hormones to favor fat oxidation and reduce muscle loss. DNP was another option commonly used as well. Obviously anabolic/androgenic steriods insulin,GH, and other growth enhancement drug were commonly stacked with thyroid hormones too.

THYROID HORMONES ARE ANABOLIC