Well, my HR is only 88 resting, but 150 when I do stepper. I'm not feeling any sides like headaches, cramps, or losing any sleep, as they have subsided. I don't see the point of going any higher.
Do you subscribe to the idea that clen loses potency and needs to be cycled, or the opposite: that one can take it as long as they need and it's not diminished?
Clen makes me feel a bit drained, but once I start working out or doing cardio, suddenly I am energized. I do feel, however, the rep output has diminished, when it comes to explosive movements like bench.