Just a curious question, but I was doing some research on clen and as we know it increases your metabolism/heart rate. I was taking clen last summer and I decided to get my blood levels check. Well my CPK values (something dealing with the muscles of the heart) were through the ROOF! They were like 10 times of what the normal should be around!!! I decided to get off the clen and check my blood levels a few weeks later and wow what do you know, they went down a good bit (but still very high). Well I continued to check my blood levels every two weeks and everytime I got the results, my CPK values continue to go down until they were within normal range. This just got me a little nervous and a bit scared to take clen again. I certainly do not want to be messing with my heart like that and I don't want to die of a heart attack at a young age, so I have just steered clear of clen from then on. Any of you bros out there are nervous or weary of taking clen and how it can possibly effect your heart in the long run?