Beginners shouldn’t be doing AMRAP =P
At least, until they learn what they can handle. Besides, it is generally implicit in AMRAP that you keep going until you literally only have a rep or two left in the tank.
Most people stop way before that.[/quote]
Doing some AMRAP curls? Knock yourself out. Almost a no-brainer. I think this concept takes on a somewhat different and highly subjective meaning on a movement like the squat.
As Many Reps As Possible before…
Your form deteriorates?
You fail a rep?
You are pretty sure you can only do one more?
You pass out?
You feel like you should stop?
You get injured?
Additionally, the relative weight factors in here. On a light weight/high rep set I may feel fine sucking gas for 5 or 6 seconds before going back into the hole. On a heavier set that bar will get racked unless I am totally sure I can get it, and once I get out of my rhythm that certainty evaporates rather quickly.
As you already stated, the AMRAP “sweet spot” is not something that a beginner is likely to have a good feel for without the awareness that comes with time under the bar spent pushing your limits.
And this lifter would recommend a conservative approach to finding those limits.