
Originally Posted by
sixoner
clenbuteral selectively targets the beta-2 androgenic receptors. it downgrades the beta-2's through continuous use and loses its effectiveness as the beta-2 receptors become desensitized usually around 14 days. the 2 week on/off protocol allows time for your beta-2 receptors to recover and then you can resume using clen effectively or you can supplement an antihistamine such as ketotifen or benadryl to upgrade your beta-2 receptors and use clen continuously for periods longer than 2 weeks at a time without interuption
eca contains ephedra.. ephedra downgrades the beta-2 androgenic receptors not selectively as it stimulates other receptors as well but it downgrades the beta-2's regardless so if you were following the 2 week on/off protocol for clen and were to take ephedra (eca stack) during your 2 weeks off you are not allowing your beta-2 receptors time to recover so when you jump back on clenbuteral it will not be effective it would be the same as if you just kept taking clen past 2weeks without supplementing something to re-sensitize the beta-2 receptors