How to film it, and what comes back
These are the movements Forge's camera tracking has been checked against real lifts. Each page covers where to put the phone, what gets measured, and what is not reliable on that particular movement.
There are four, because four have been validated. We are not publishing a page for every exercise in the library and calling the output coaching. See the full validation list.
Back squat
Phone on the floor or a low box, landscape, about three metres back, with the whole athlete in frame from head to feet at the bottom of the rep. Behind the lifter is what has been tested.
Bench press
Any angle you can film from is an angle Forge will measure, see the caveat for what each one costs. Square to the side, camera level with the bar, is the most accurate, because it is the only view where a lying athlete's own height can be used to set real-world scale. From the foot of the bench or behind the head, scale comes from shoulder breadth instead, which works from those angles and is looser.
Pendlay row
Side-on, low, the full bar path in frame from the floor to the athlete's chest. The dead stop on the floor between reps is what makes this one segment cleanly.
Box jump
Side-on, far enough back that the athlete and the whole box stay in frame at the top of the jump. Landscape, and keep the phone still, this mode reads the box's top edge out of the footage.