Where to put the phone
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.
What comes back
- Bar speed on the way up, per rep and across the set
- Depth, as range of motion
- Bar path deviation from vertical
- How much the bar slowed from the first rep to the last
What is not reliable here
Filming from behind means forward-and-back drift lands on the depth axis, which a single camera estimates rather than measures, so it is the least reliable number in the set. Side-on gives a better answer to that specific question and a worse one to everything else.