The Most Important Exercise After ACL Surgery

The Most Important Exercise After ACL Surgery

The journey back to full, pain-free function after an ACL injury or ACL surgery is often a long, difficult process. Unfortunately, many athletes find themselves dealing with long-term issues and high re-tear rates after an initial surgery, largely due to subpar rehab care. And the only thing worse than tearing an ACL, is tearing the same ACL twice!

When going through rehab after an ACL tear or ACL surgery, one of the MOST important keys to successful rehab is gaining back full quadriceps function. When we talk about full quadriceps function, we mean that the quadriceps muscle has to regain full strength and power in order to control the knee during daily tasks and sports activities.

And here is where people recovering from ACL injuries or surgeries run into problems. Most PTs are taught in PT school that they need to focus on “closed kinetic chain” exercises (exercises in which the foot stays planted on the floor, such as squats, split squats, step downs etc), and they need to AVOID open kinetic chain knee extension (ie leg extensions).

Leg extensions are not only safe to do after ACL surgery (although they may have to be modified/constrained in the beginning), but leg extensions are also the ONLY exercise that truly isolate the quadriceps muscle, and can ensure that we are training the muscle to its fullest potential.

While exercises like squats, split squats, step downs, and deadlifts are great and should ABSOLUTELY be used in ACL rehab, patients recovering from ACL injuries and surgeries have a habit of changing their movement during these exercises so that they’re unloading the knee and quadriceps muscle and shifting more of the work to the hip muscles. And while we want to ensure that the hip muscles are strong as well, if this isn’t corrected over time, and the quadriceps aren’t trained and developed to their fullest potential, it leaves the person at high risk of not only a limited recovery and performance once they’re done with physical therapy, but they’re left at a risk of re-tear as well. 

Because of this, leg extensions are probably the single most important exercise that you can do after an ACL injury or ACL surgery!

Properly using the leg extension exercise can help us in a number of different ways:

  • Increased quadriceps muscle size
  • Increased strength of the quadriceps
  • Increased power of the quadriceps
  • Improved ability to decelerate quickly on the field
  • Improved ability to quickly cut and pivot on the field

WHEN and HOW the leg extension is programmed for a person after an ACL surgery will depend upon the specifics of their case, but they should absolutely be used in ACL rehab.

We have worked with numerous athletes after they have undergone ACL surgery and had subpar rehab at other, generalized physical therapy clinics, and often what we see is pretty alarming.

It’s not unusual for us to see that a client’s quadriceps on the surgical side is 30, 40, or even 50% weaker than the quadriceps on the non-surgical side, despite being months (or sometimes even years) out from their surgery. If an athlete tries to get back to competitive sports with THAT much strength loss in their quadriceps, they’re at best going to have limited performance on the field, and at worst at a much higher risk of re-tear than is needed.

This scenario can largely be avoided with an expertly made ACL rehab program that includes leg extensions as a staple part of the rehab plan. If you, or somebody you know, are dealing with an ACL injury or have gone through ACL surgery and are looking for help getting back to 100%, click below to speak to somebody from our team to see if we can help you reach your goals.

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Ryan VanNieuwenhuyze

Barbell Physical Therapy & Performance

"We Help Active Adults, Lifters, And Athletes Solve Their Pain And Get Back To The Workouts And Sports They Enjoy Without Medication, Surgery, Or Stopping The Activities They Love."