Leg Extension form check
Film a set from your phone and FORMA counts the reps and tells you what went wrong on each one. It runs entirely on your device — the video never leaves your phone, and you do not need an account.
Check my leg extensionHow to film it
Film from the side, seated, with your knee clearly in frame.
What it measures
- Knee angle — the angle the rep is counted from and the live readout on screen.
- Hip angle — the second angle it watches for the faults that matter on this lift.
How a rep is counted
A rep is counted when your knee angle passes 105° and comes back past 150°. Depth is judged separately, so a short rep still counts — and still gets told it was short.
Form is judged at the top of the rep, where the lift is hardest and where it breaks down.