theguerillachemist

Terbutaline sulfate is a prescription bronchodilator that, like clenbuterol is also a beta-2 adrenergic agonist. Chemically, it has a tertiary butyl group which makes its more selective for beta-2 vs beta-1&3. It also lacks a para hydroxy group on the ring which helps prevent its metabolism by COMT.

In this study, researchers gave 18 young and active males 5mg/30kg twice a day or a placebo for 4 weeks(the normal Rx dose is 15mg/d). Subjects in the terbutaline group noticed an increase in maximal muscle contraction(97N vs the placebo), as well as an increase in max and average peak power in cycling(25W vs -7W in placebo). But the most interesting effect observed was an increase in LBM by 1.7kg(3.7lbs). Not only that, but subjects also lost 1.3kg(2.8lb) of fat. Not bad body recomposition in 4 weeks with no change in diet. Researchers theorized that the muscle gain was attributed to a significant increase in follistatin expression.

Follistatin is a negative regulator of myostatin. As expected, taking this high of a dose of beta-2 agonists caused heart palpitations, restlessness and shakes/tremors, similar to using ephedrine or clenbuterol. This is a very promising study that shows in a controlled setting not only the anabolic properties of beta-2 agonists but also the fat loss abilities.