Single Leg Jump for Height Test
An objective way to measure knee extensor performance asymmetries by testing each leg individually.
What is a single leg jump for height test?
Plyometrics are exercises that enable a group of muscles to reach maximal strength in as short a time as possible. They help bridge the gap between speed and strength training. Single leg jump (SLJ) testing gives practitioners an objective measure of power and movement quality improvements during the final stages of rehabilitation for lower limb injuries. Additionally, SLH testing help to quantify asymmetries as they assess each leg independently of the other.
SLJ for height (SLJ H) test primarily reflects knee extensor performance capabilities to create vertical propulsion. A practitioner can perform the SLJ H test to evaluate the following areas of functional movement performance:
Muscle strength reserves and power
Propulsive and absorptive strategies with foot-ground interactions
Degree of inter-limb asymmetry for all of the above components of movement performance
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Important: The subject must face the same direction throughout the test. So for the Single Leg Jumps for Distance, the subject can either continuously jump forward (space permitting) or walk back to the starting point between each jump. See the video below for the protocol.
1. Tester navigates to the measure page of the Plantiga web application and selects either the SLJH test.
2. Tester selects the subject that will be performing the activity. Address any warnings that may come up once they have been selected.
3. Tester instructs the subject to stand still with hands on hips and feet planted firmly on the ground.
4. Tester begins the SLJH test, and the subject remains still as the stopwatch counts down from 5.
5. Once ready, the subject performs three jumps with each leg, alternating legs between each jump. It does not matter which leg the subject chooses to start with, and they can perform these jumps at whatever pace they choose.
6. Once all jumps have been performed, the tester instructs the subject to stop and plant their feet firmly on the ground.
7. The tester stops the stopwatch once still, and the subject remains still for 5 seconds.
8. Tester fills out optional information (RPE, Pain, Floor type...) and saves the Single Leg Jump Test
What does Plantiga measure?
Jump height asymmetry: a comparison of left vs. right max jump heights to indicate thigh muscle strength and power performance capabilities.
High jump height asymmetry (> 10%) indicates a compensatory shifting of demands due to an affected and/or weaker limb. It is a vital rehabilitation functional milestone indicator for return to activity after orthopedic and musculoskeletal injury.
Poor symmetry scores (<4/10) occur when one limb is significantly underperforming and requires strengthening interventions.
When combined with SLJ distance testing, muscle symmetry scores can identify trainable muscle deficits between the hip (glutes & hamstrings) vs. knee (quadriceps) to help improve overall movement symmetry and efficiency.
Vertical take-off acceleration (VTA) asymmetry: a comparison of how quickly the left vs. right foot leaves the ground immediately after toe-off.
High VTA asymmetry (> 10%) occurs when the opposite limb's quadriceps musculature and surrounding tissues are fatigued, weak, or experiencing pain.
Vertical landing acceleration (VLA) asymmetry: a comparison of the ability of the left vs. right to absorb impact when the foot lands on the ground.
High VLA asymmetry (> 10%) occurs when landing more abruptly on one limb than the other.
How can my athletes benefit from SLJ H testing with Plantiga?
To simplify data interpretation and provide actionable movement insights to our users for better rehabilitation and performance outcomes, we’ve created instant and customizable activity reporting tools that can be accessed and shared within minutes.
