90 90 Test


The 90 90 test is a great sports industry standard. this Straight Leg Raise Test also known under the name of Active Knee Extension Test (AKET) is a test to assess hamstring length and the presence of possible hamstring contracture. See below to learn more about the test and how to best perform it.


  • The 90/90 test also called the Active Knee Extension (AKE) Hamstring Flexibility is a test that measures the hamstring muscular length as well as the range of extension of the active knee when in hip flexion.
  • To preform a 90/90 test the individual being tested needs to lay down in a supine position and flex their hips and knees into a 90 degree angle with their back in a neural position. Once in position the individual needs to grip onto the superior portion of their hamstring in order to stabilize the inferior region. The individual can now begin to extend a singular knee to their max, all while maintaining the current 90 degree angle of the hips. Once they reach their maximum extension capacity, they can then begin to flex their knee in order to return back to a 90 degree angle, either ending the test or repeating this sequence on the alternate leg.

Steps for Athlete

  1. Have the athlete begin by laying flat on their back with straight legs.
  2. Then have them begin to raise both legs simultaneously, flexing their knees and hips until they hit a 90 degree angle, holding this position.
  3. Once in position have the athlete move their hands towards the exterior portion of their hamstrings, securing a firm hold.
  4. The athlete can then begin to a singular leg only extending the knee, with the hip staying at 90 degrees.
  5. The athlete should be trying to extend their leg to the best of their abilities in order to provide the best gauge of their range of extension.

Recording Position

  • Side View, have those recording to stand 3ft away from the athlete or until the athlete is completely in frame, maintaining a firm and still hold of their recording device.


By using the 90 90 Test to asses hamstring length/range of motion and the presence of possible hamstring contracture, you can reduce the risk of hamstring injury and work to increase leg range of motion.