T4 (L-Thyroxine) is produced in higher amounts than T3 (triiodothyronine) and functions as a T3 precursor.
Around 40% of T4 in the body is converted into T3 through the process of removing an iodine group from its outer ring (deiodination).
Once converted, the body’s cells use T3 to deliver oxygen and generate energy within various tissues and glands within the body.
The thyroid gland generates 20% of the body’s total T3 whereas the remaining 80% is created outside of the thyroid gland in other tissues.
Most people secrete between 10-22 mcg T3 and 94-110 mcg T4 each day.
l-thyroxine t4 bodybuilding
In the world of bodybuilding, where every ounce of fat matters, T3 and T4 play significant roles. These thyroid hormones, especially T3, are sought after for their fat-burning properties.
Due to the more aggressive nature of T3 compared to T4, many bodybuilders have used it as a tool for rapid weight loss in order to enhance their performance, make weight, or shed necessary body fat to obtain their desired physique.
T3 Dosage Bodybuilding
Athletes typically run anywhere from 25-50 mcg on average over the course of 8 weeks to enhance fat loss.
If using a tablet or liquid form, competitors will generally start their dosage at 12.5mcg and then gradually increase their daily dosage by 12.5mcg every 3 days until they reach 50mcg.
They will continue to run 50mcg through the end of their contest, however, some coaches may slowly lower their clients’ dosage a few weeks prior to competition in order to reduce the loss of lean mass or prevent muscles from flattening out the day of the show.
After the completion of their contest, most competitors will use the same protocol for tapering off and drop their daily dosage by 12.5 mcg every 3 days and run the final 3 days of their T3 cycle at 12.5mcg total.
Those who opt for capsule form may choose to run 25mcg for the entire duration or they may follow a similar tapering method depending on each capsule’s concentration.
In most cases, capsules are extremely hard to dose properly, especially if they contain higher amounts of T3, such as 50mcg per capsule.
You won’t see most bodybuilders or fitness models purchasing Synthroid or generic T4 to enhance their physique as T3 is nearly 5x more potent than T4 and under normal conditions, the body only converts up to 40% of T4 into T3.
l-thyroxine T4 Bodybuilding Dosage
If using a T3:T4 combo, it’s best to purchase a product that contains a 1:2 ratio.
For example, some competitors will use this thyroid hormone combo in liquid form.
Each bottle typically contains around 30mL and each mL should contain around 100mcg:200mcg of T3 and T4 respectively.
However, it’s best to not exceed a limit of 50mcg:100mcg so competitors should usually only need to use about 0.5mL per day once they’ve reached the peak of their cycle.
T4/L-Thyroxine Side effects
Side effects from excessive doses include weight loss, trouble tolerating heat, sweating, anxiety, trouble sleeping, tremor, and fast heart rate. Use is not recommended in people who have had a recent heart attack. Use during pregnancy has been found to be safe. Dosing should be based on regular measurements of thyroid-stimulating hormone (TSH) and T4 powder levels in the blood. Much of the effect of levothyroxine is following its conversion to triiodothyronine (T3).
L-Thyroxine powder Chemical Properties
Melting point 235 °C
alpha -5 º (1N NaOH:EtOH 1:2)
density 2.4440 (estimate)
Fp 9℃
storage temp. Keep in dark place,Inert atmosphere,2-8°C
solubility Dissolves in 4M ammonium hydroxide in Methanol at 50mg/ml
pka 2.2(at 25℃)
form Powder
Boiling point 576.3±50.0 °C(Predicted)
color White to Pale Brown
Water Solubility insoluble
Sensitive Light Sensitive
Merck 9491
BRN 2228515
InChIKey XUIIKFGFIJCVMT-LBPRGKRZSA-N
CAS DataBase Reference 51-48-9(CAS DataBase Reference)
EPA Substance Registry System L-Thyroxine (51-48-9)
Contact us, you can buy L-Thyroxine T4 powder
More Introduction:https://en.wikipedia.org/wiki/Levothyroxine
