I match Cathe on some weights (lower body, biceps, shoulders), exceed what she uses on some (back, bench presses), and use less than her on some (flyes, some triceps). I've used Cathe's weight workouts from the beginning (and couldn't match, let alone exceed, her weights back then), so I pretty much know that if she uses such-and-such a weight for body part X, I will do best with one that is (the same/heavier/lighter). (Like in GS Back/shoulders/biceps, when she grabs just 8# for the partial reps, or when she grabs 15# --I think--for bicep work in PH, I KNOW I should go lighter than usual!)
As for when to go up: the last 2 reps of a set should always be somewhat difficult, but still possible to do with good form. Once those reps become easy, it's time to move up in weight. (With regular gym weight training, you set a range of reps, say 8-10, start with a weight that allows you to do the lower end of the range, then go up in weight when you can do the upper range of the reps--some recommend to up weights when you can do the upper range of the reps with your current weight for two workouts in a row).
>I wanna know how can you all tell what she has in her hands
>for dumbells when TV will distort the image?
>
>In most workouts, she tells us what weight she is using.
