i have used clen few times. Once I took a dose before the gym and did deadlifts. I hard a hard time breathing between sets. I thought it was pretty much worthless IMO
Sweated , heart raced, shakes. The results were not worth the jitters and sleepless nights.For the first week, then like usually the stuff stops working after a week . Then tried it agian 3 weeks later and it worked full blast again.
If you are going to use clen time it in the opposie time of the day as you're workouts to avoid the breath problems
Ephedrine works just as good and actually has less side effects ( even just 25mg ) is enough to speed up the fat burning process.