Single Leg Jump for Height

An objective way to measure knee extensor performance capacity on each leg.

Table of Contents

• What is a Single Leg Jump for Height test?
• Test Instructions and Demo
• What do the metrics mean?

What is a Single Leg Jump for Height test?

Single Leg Jump (SLJ) testing can give practitioners an objective measure of leg power and movement quality and can be used to quantify side-to-side asymmetries, as each leg is assessed independently. SLJs are plyometric exercises that require a group of muscles to reach maximal strength in as short a time as possible.

Vertical SLJ primarily involves the knee joint structures and quadriceps musculature. Implementing the SLJ for Height (SLJ-H) test can provide practitioners with an objective measure of an athlete's side-to-side leg power, movement quality and strategies for propulsion and absorption.

Single Leg Jump for Height test instructions:

Start the Test

1. In plantiga.io, go to Record (left sidebar)
   1. From the Activity Type drop-down, select Single Leg Jump Height
   2. From the Select People drop-down, select the athlete profile(s) being tested

Check for Warnings

2. It's important to resolve all warnings before starting or data may not be recorded.
3. Click Start

Calibrate

4. Instruct the athlete to stand still with both feet on the ground for 3 seconds at the start of the assessment

Perform the Test

5. Instruct the athlete to put their hands on their hips

   Once ready, have the athlete perform 6 total jumps - 3 on each side, alternating sides (ex. L, R, L, R, L, R)

   Cue: Instruct the athlete to jump as high as they can

   1. The athlete can choose which leg to start on and should aim to jump as far forward as they can with a controlled landing
   2. They must jump and land on the same leg, and be able to hold the landing for at least 1 second

End the Test

5. Click Stop when finished
   1. (Optional) Add contextual notes
6. Choose one of the following:
   1. Done – finish and save
   2. Next – start another assessment
   3. Reset – discard the assessment

Single Leg Jump for Height demo

What do the metrics mean?

Jump height asymmetry: a comparison of left vs. right max jump heights to indicate thigh muscle strength and power performance capacity.

• When combined with Single Leg Jump for Distance testing, large jump height asymmetries can indicate trainable muscle strength and power deficits between the hip (glutes & hamstrings) vs. knee (quadriceps).

Push-off asymmetry: a comparison of the left vs. right side capacity to accelerate off the ground.

• Push-off asymmetry may occur when the one limb's hip musculature and surrounding tissues are fatigued, weak, or unable to produce enough energy to get off the ground.

Impact asymmetry: a comparison of the ability of the left vs. right to ability to absorb load when the foot hits the ground.

• Impact asymmetry may occur when the athlete lands stiffer or more abruptly on one limb than the other, or if they are using a protective strategy.