Can astronauts jerk off or toss the troff in space? Would their heart monitors would show it to be elevated? Or can or has any two astronauts ever had sex in space?
Did you know that you can orgasm without the associated spike in heart rate? Takes some practice, but you can even separate ejaculation and orgasm, and still have both.
It's alllll about how much you're willing to practice. It comes down to breath control combined with awareness of each stage of arousal and managing the two.