Power · Pro test
Drop jump RSI: how quickly does your client rebound?
Your client steps off a box and jumps straight back up. From high-speed phone video, MovePath measures ground contact time and rebound height, and divides one by the other to give RSI.
Front view · high-speed videoOne drop per videoResult: RSIAbout 3 min
What it measures
RSI = rebound height (m) ÷ ground contact time (s), to two decimal places. Height uses the same flight-time method as the countermovement jump.
Two jumps can reach the same height, but a longer time on the ground means a slower rebound. RSI puts height and speed into one number.
Choose a box height of 20, 30, 40 or 50 cm. Don't compare RSI across different box heights.
Where to put the phone
- Front view about 3 m, lens near the floor (30–50 cm)Box behind the client, landing spot 30–50 cm in front of it. Keep the head in frame at the top of the rebound.
- High-speed video, uncutFilm with a high-speed mode such as slow motion, and pick the clip as filmed without trimming it in the gallery. One drop per video.
- Step off, don't jump offStart recording once the client is on the box. Hands on hips, step forward off the box, and as soon as both feet land, jump as high as possible. Stand still for over two seconds after landing.
What the report shows
- RSIThe highest RSI and the average across drops, with contact time (ms) and height (cm).
- Change since last timeOn a re-test, the first sentence states the change since last time, and a trend chart shows the same test over time.
- PhotosContact, take-off and landing, face blurred. Taken only with the client's photo consent and kept only on the trainer's phone and in the PDF. Report links carry no photos.
- Test video ProReplay the ground contact phase in slow motion to check the RSI.
Reference data
There is no age- and sex-based reference table for this test in the report yet. Instead, the report shows the change since the same client's previous test. We only add tables whose numbers we have checked against the original paper.
Please note
MovePath is not a medical device. This test records measurements to guide exercise; it is not a diagnosis. App readings may differ from a goniometer, tape measure or stopwatch. Use them to compare the same client's first test with today's, measured the same way.
This is a Pro test. Pro opens after launch, and early access sign-ups hear about it first.
Before you invest in equipment, start with your phone
One phone, 3 minutes, one report. Client photos never leave your phone. Email us and we'll let you know when early access opens.
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