Increase Lean Muscle Mass Improves Muscle Recovery Fat Loss Testolone, otherwise known as RAD140, has a high affinity for muscle and bone receptors, meaning it will help you build muscle quite rapidly. RAD 140 starts working shortly after ingestion, and begins binding to skeletal muscle androgen receptors, signaling your body to build muscle. In fact, within a week, most users notice an increase in training capability, faster muscle growth, faster recovery, and accelerated fat loss, too. Rad 140 is an investigational compound still awaiting FDA approval and is not a dietary supplement. For research purposes only