Children's Hospital Colorado

ACL Recovery Time: When Can I Play Again?

An athletic trainer checks a young male athletes knee after a knee injury.

You child hears a pop. You see swelling. Someone on the sidelines says the acronym – ACL. Your world momentarily stops. Exams, physicians, MRIs and possibly ACL reconstruction surgery follow soon after. Now what?

The anterior cruciate ligament (ACL) is one of the main stabilizing ligaments within the knee complex. Research has shown about one in every 60 young athletes will experience an ACL tear at some point over the course of their athletic career.

The rehabilitation process following this injury is significant and should not be taken lightly. Many sources have reported a large range of timelines regarding length of time between injury and return to high level sports. As more research is performed within the adolescent population, tissue-healing and length of time prior to achieving symmetrical strength is being extended.

How long does it take to heal from an ACL injury?

The time to return to sport can vary greatly because every child heals and regains strength at different speeds.

Our physical therapists focus on regaining strength, balance and range of motion post-operatively and addressing faulty movement patterns that may contribute to the original injury itself. This approach helps decrease risk of re-injury on the same side and assists with preventing additional injuries on the opposite side.

In order for this process to be completed thoroughly and safely, Children’s Hospital Colorado sports medicine experts use a 9-12 month average timeframe for returning to sport.

How do you test to see if I’m ready to return to sport after ACL injury?

Athletes should have clearance from a physician before returning to their sport to confirm they have symmetrical strength, range of motion, power production and balance.

Our physical therapists will conduct the return-to-sports test once deemed appropriate. This test measures:

  • Endurance
  • Strength
  • Power Production
  • Balance
  • Agility


In order to “pass” the return-to-sport test, the athlete must achieve more than 95% in each category when comparing the surgical side to the uninvolved side. Quality of movement and form is also assessed by the testing physical therapist.

The physical therapist will discuss gradual progression back to sport(s) to help ensure that a safe return to the field or court is achieved.

Learn about ACL rehabilitation from our Sports Medicine Center experts.