verjtestJump testing for the whole squad, with one phone
Film each athlete from the side. verjtest measures jump height from flight time and reactive strength from ground contact, stores every result against the athlete, and shows who is down on their own baseline.
Already have a flight time or video frame count? Use the free jump height calculator for an immediate estimate in centimetres and inches.
Why
Most clubs either buy a jump mat or do not test at all. Without regular numbers, a coach cannot see fatigue building up or progress across the season. verjtest is for football, basketball and volleyball clubs that want to test every month with the phone they already carry.
What it measures
Jump height
From flight time: the moment the feet leave the ground to the moment they land, read from the ankle's vertical movement. The same principle a jump mat uses.
Reactive strength index
For drop jumps and repeated jumps: jump height divided by the time on the ground before it. Shows how well an athlete uses a short contact.
Countermovement depth
The smallest hip–knee–ankle angle before take-off. A change in depth next to a change in height usually means the athlete jumped differently, not that they are tired.
A cross-check on every jump
The hip's rise during the flight gives a second, independent height. When the two disagree, for example after a landing with bent knees, the result says so and the coach decides whether to keep that jump.
How a test session works
- Set the phone up once. Side view, at hip height, a few metres away, with the whole athlete in frame. Use the same spot and distance every month.
- Film each athlete. A few countermovement jumps, a drop jump from a box, or a set of repeated jumps. Use the phone's own camera at 60 frames a second or more.
- Check and save. The clip is analysed on the phone. You see each jump, untick any bad trial, and save the result to the athlete.
- Read the squad table. Each athlete's latest result against their own baseline, as green, amber or red. Open an athlete for their trend over the season, or export everything as CSV.
The squad table
Each athlete is compared with their own first tests of the season, never with teammates. A drop of 5% in jump height turns amber and 10% turns red. Reactive strength varies more from test to test, so its bands are wider.
| Athlete | CMJ | RSI repeated | Depth |
|---|---|---|---|
| Athlete A | 38.2 cm +1.4% | 1.62 −2.0% | 94° +1° |
| Athlete B | 33.0 cm −6.8% | 1.31 −9.1% | 101° +8° |
| Athlete C | 29.4 cm −12.5% | 1.48 −3.3% | 96° 0° |
An example of the layout, not real athletes. ● holding, ▲ watch, ■ down.
What the numbers are, and are not
These are estimates from a phone video. They are comparable over time when the setup stays the same: same place, same distance, same camera height, same frame rate. They are not laboratory measurements.
At 30 frames a second each frame is 33 milliseconds, which is a few centimetres of height. At 120 or 240 frames a second, which many phones offer as slow motion, the timing is several times finer. The result screen says which frame rate a clip was filmed at and what that means for the height.
Your data
Clips are analysed on the phone and are not uploaded unless you choose to keep one with an account. Without an account, the squad and its results stay on the device. With one, they sync to every device you sign in on, and nothing on the device is lost when you sign in. Privacy.
See it with your squad
Tell us about your club, the sport and how many athletes you test, and we will get in touch to arrange a demo.
Book a squad demo