Learn Russian: Вам надо проверить пульс, пока вы не допрыгались. - You need to check your pulse before you ask for trouble.

It's formed using the base verb прыгать (to jump) along with the prefix до- and the postfix -ся. This specific combination (до- + -ся) is used to show that an action was done to the point of a negative limit or bad outcome. Literally, it implies "jumping until you ruin things," which idiomatically translates to "pushing your luck" or "asking for trouble."

Why is there a не in пока вы не допрыгались when the English translation says "before"?

The construction пока не followed by a perfective verb usually translates to "until" or "before" an event happens. While не is a negative particle, the Russian logic here is "while the event has not yet happened." So, пока вы не допрыгались literally means "while you haven't yet pushed your luck too far," or more naturally, "before you ask for trouble."

Why is допрыгались in the past tense if this is a warning about a future action?

You can use the future perfective here (пока не допрыгаетесь), but the past tense is very common in spoken warnings like this. Using the past perfective frames the negative outcome as a completed fact. It makes the warning feel more urgent, like saying "fix this before the bad result is already a done deal."

Just as a refresher, why do we use the dative Вам here instead of Вы?