king im on my 4th day of my cycle and i got 2 mass bottles and 1 bulk and reboot. i gotta stay in touch with u through this cycle. but i feel a little light headed after a dose not sure about heart rate but for my supports i got taurine, hawnthorne berry and some coQ10-blood &cardiovascular support. and planning on running cycle assist durring pct. but try picking up some coQ10.