Exercises for ACL Injuries: What Physical Therapists Recommend

Learn how physical therapy helps treat ACL injuries and get recommended knee exercises from physical therapists.

Published Date: Mar 12, 2024

Exercises for ACL Injuries: What Physical Therapists Recommend

Learn how physical therapy helps treat ACL injuries and get recommended knee exercises from physical therapists.

Published Date: Mar 12, 2024

Exercises for ACL Injuries: What Physical Therapists Recommend

Learn how physical therapy helps treat ACL injuries and get recommended knee exercises from physical therapists.

Published Date: Mar 12, 2024

Exercises for ACL Injuries: What Physical Therapists Recommend

Learn how physical therapy helps treat ACL injuries and get recommended knee exercises from physical therapists.

Published Date: Mar 12, 2024
Table of Contents

You don’t have to be Tom Brady to come back from an ACL injury. Yes, the former Patriots quarterback was sidelined with an ACL tear at the beginning of the 2008 season but played for 14 more seasons winning four more Super Bowls, but he’s not some anomaly. Even if you aren’t a professional athlete, you can recover from an ACL injury and return to all the activities you enjoy.

“An ACL injury can feel pretty upsetting,” says Vanessa Matos, PT, DPT, a physical therapist at Hinge Health. “People think they’re going to have knee pain forever and won’t be able to return to their prior level of function.”

But many people — even those without the resources and white-glove rehab available to professional athletes — can recover completely. “You can return to high-level activity after an ACL injury with dedicated and consistent work,” says Dr. Matos. And you don’t always need surgery, either. Some evidence suggests that physical therapy might work as well as surgery for some people with a torn ACL.

Read on to learn more about anterior cruciate ligament (ACL) injuries — their symptoms, causes, and treatment options — including exercises recommended by Hinge Health physical therapists.

Our Hinge Health Experts

Vanessa Matos, PT, DPT
Physical Therapist
Dr. Matos is a Hinge Health physical therapist with a special interest in treating orthopedic injuries in athletes and patient education.
Jonathan Lee, MD, MBA
Orthopedic Surgeon and Medical Reviewer
Dr. Lee is a board-certified orthopedic surgeon and an Associate Medical Director at Hinge Health.
Dylan Peterson, PT, DPT
Physical Therapist and Clinical Reviewer
Dr. Peterson is a Hinge Health physical therapist who focuses on developing clinical exercise therapy programs and member education.

What Is the Anterior Cruciate Ligament?

The anterior cruciate ligament (ACL) is a fibrous band of tissue in the knee joint that connects the femur (thighbone) to the tibia (shinbone). It’s one of four primary ligaments in the knee joint, and plays a pivotal role in maintaining knee function. It provides stability to the knee when your shinbone moves forward away from your body, prevents excessive rotation, and ensures knee joint alignment during activities like running, jumping, and pivoting.

The ACL is the most commonly injured knee ligament, with more than 200,000 people in the U.S. tearing an ACL each year, according to research.

What Is an ACL Injury?

Anytime there’s a sudden twisting or pivoting motion of the knee, there’s the potential to irritate, sprain, or tear the ACL. ACL injuries often occur when playing sports like football, soccer, tennis, basketball, pickleball, or downhill skiing, where there are frequent starts, stops, changes in direction, lateral movements, and, in the case of football, high-impact collisions. 

ACL injuries can occur outside of sports, like during a car accident. They can even happen in everyday life when you're chasing after kids, playing with your dog, moving quickly to catch something, or avoiding an obstacle, like while hiking. Uneven surfaces like grass and trails can make these movements riskier. But that doesn’t mean you should avoid these activities. Staying active and strengthening muscles that support your knees can help prevent an ACL injury or a reinjury.

ACL injuries are divided into three levels of severity: 

  • Grade 1 is a sprain, in which the ACL has been overstretched, not torn. The ligament still provides stability, and you haven’t lost any knee function. You may have some pain and swelling, but you can walk on it and perform most everyday activities.

  • Grade 2 is a partial tear, in which the ACL has been overstretched to the point that it is loose and can’t provide full stability, making walking and stair climbing difficult. You may feel like your knee is going to give out as you do these activities, especially when changing directions. 

  • Grade 3 is a full tear, sometimes referred to as a rupture. When this happens, you’ll feel less stable putting weight on your injured leg, and walking will be more difficult.

ACL Injury Symptoms

No matter what caused your injury, the symptoms of an ACL injury are generally the same, including:

  • Sharp knee pain at the moment of injury

  • Feeling or hearing a popping sound when the injury occurs

  • Swelling in the first few hours

  • Loss of range of motion

  • Difficulty walking or bearing weight on the injured knee

  • Sense of instability

  • Feeling like the knee is going to give out or having the knee give out

  • Soreness

ACL Injuries: A Hinge Perspective

Anytime you hear that you’ve torn something in your body, it’s perfectly natural to be a little alarmed. And it’s understandable if you feel hesitant to bear weight on an injured ACL, and you may worry about reinjuring yourself. You may be fearful of surgery or possible long-term effects like arthritis. Your concerns are valid, but take heart: Ligaments, including the ACL, are resilient bands of connective tissue. They’re designed to recover and heal.

One of the most important components of recovery — whether you need surgery or not — is movement. As our Hinge Health care team likes to say, movement is medicine. It helps to maintain range of motion, brings nutrients to the knee joint for healing, and strengthens supporting muscles. 

A physical therapist can help you overcome any hesitations you have about moving with a torn ACL. They can design an exercise program tailored to your symptoms and abilities. You can see a physical therapist in person or use a program like Hinge Health to access a PT via telehealth/video visit.

Causes of an ACL Injury 

ACL injuries occur when the anterior cruciate ligament absorbs too much force. Here are some common ways that can happen:

  • Rapid change in direction

  • Sudden twisting

  • Direct impact to the knee, such as a car accident, fall, or collision while playing sports

  • Abrupt stop

  • Pivoting when your foot is firmly planted

  • Landing awkwardly, perhaps after a fall or jump

Treatment Options for an ACL Injury

Treatment for ACL injuries typically involves two options: non-surgical and surgical approaches. Treatment depends on the severity of the injury, as well as other factors such as your activity level and overall health. Non-surgical approaches may be recommended for mild or moderate injuries or for those who are good candidates based on lifestyle, age, and other factors.

Here are some of the conservative treatment options for an ACL injury:

  • P.E.A.C.E and L.O.V.E. protocol. This new self-care model replaces the R.IC.E. method (rest, ice, compression, and elevation), making movement — instead of rest — a central part of your recovery plan while still protecting and rehabbing the injured knee.

  • Ice and heat. Ice can help reduce swelling and pain immediately following an injury. Apply ice for 10 to 20 minutes at a time as needed. After the initial swelling has subsided, you can switch to heat if that feels better to you.

  • Physical therapy. Physical therapy is a research-backed treatment for ACL tears. In addition to recommending exercises, a physical therapist (PT) may also use neuromuscular stimulation (low-level electrical impulses that cause muscles to contract) to enhance strength and function in surrounding knee and leg muscles. Whether or not you have surgery, physical therapy should be part of your recovery program to improve coordination and confidence in movement, stability, strength, power, and function so you can return to the activities and sports you enjoy. People who get back to doing the activities they did before their injury report a higher quality of life than those who don’t, research shows.

  • Knee bracing. If knee instability is keeping you from being active, a brace may help, but it’s not a replacement for exercise therapy. A brace may be helpful immediately following surgery, but overall evidence for its effectiveness after an ACL injury is inconclusive, so you should follow the advice of your doctor or physical therapist. 

  • Patience. You can make a full comeback after an ACL injury, but it’s going to take time, so don’t rush your recovery. “One of the greatest predictors of ACL reinjury is returning to sports too quickly,” says Dr. Matos. That said, you’ll be able to return to everyday activities sooner.

ACL Surgery: What to Know

The thinking on surgery for torn ACLs is evolving, and doctors may not be as quick to opt for a surgical treatment as they may have been in the past. Some research suggests that rehabilitation and physical therapy may provide similar benefits as surgery for some people. 

While some ACL tears may require immediate surgery, the recommended approach is to start with prehab exercise therapy before surgery to determine if function and stability can be regained without it.

“Some people have really good results without surgery,” says Dr. Matos. “Our joints are stabilized by many structures, not just the ACL. There's the joint capsule, the meniscus, and other ligaments and muscles surrounding the joint. The stability of the joint is a combination of all of these structures.” For some people, rebuilding strength in these areas may provide enough stability that surgery isn’t needed.

For others, surgery may still be recommended after prehab and that’s okay. The goal is to get you back to doing the activities you enjoy, and sometimes that requires surgery. Don’t think your prehab was for nothing — whether you have surgery or not, physical therapy is a pivotal part of recovery. All the strengthening you did before surgery will aid in your post-op recovery as you return to PT to continue to regain strength and function. 

Exercises to Help Protect Your ACL

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These exercises focus on strengthening the primary knee muscles, the quadriceps, and surrounding muscles, like the hamstrings, glutes, and core, to provide a good support network for your knees. The first two moves are examples of early rehab exercises that activate the quads without placing stress on the knee joint. They also help to alleviate swelling by moving fluid and nutrients around the knee joint. The next three moves are more dynamic and target multiple muscle groups to build more strength and improve function. All these exercises can help keep your knees healthy whether you’re looking to prevent an ACL injury or avoid a reinjury. They can also help to minimize the effects of other knee problems, like arthritis, in the future.

The information contained in these videos is intended to be used for educational purposes only and does not constitute medical advice or treatment for any specific condition. Hinge Health is not your healthcare provider and is not responsible for any injury sustained or exacerbated by your use of or participation in these exercises. Please consult with your healthcare provider with any questions you may have about your medical condition or treatment.

Prevention of an ACL Injury

Injuries happen, but here are some strategies that can help reduce your risk and minimize the severity if an ACL injury does occur.

  • Warm up before physical activity. A five to 10-minute dynamic warm-up prepares your body for more intense activity and has been shown to reduce injury. Try butt kicks, side shuffles, high knees, and squats to warm up your lower body.

  • Exercise regularly. You’re more likely to get injured if you’re inactive during the week and then go out and play hard on the weekend. An exercise program that includes a combination of dynamic stretches, agility work, strength training (including the core), and even plyometrics (jumping activities) may help prevent ACL injuries, according to research

  • Check your technique. If you’re starting a new activity, lessons can be helpful to ensure good technique during high-risk activities like downhill skiing, soccer, or pickleball. A physical therapist can also provide sport-specific recommendations.

  • Wear proper equipment. Running shoes aren’t appropriate for soccer, tennis, or pickleball because they don’t have the lateral support needed for activities with a lot of side-to-side movement and quick changes in direction. If you’re a skier, make sure your bindings are properly adjusted. Properly fitted, sports-specific footwear can help protect against injury.

PT Tip: Strengthen Your Core and Hips, Too

“If you think of an ACL injury as an isolated knee injury, you’re missing many pieces of the puzzle,” says Dr. Matos. “You need stability from the top down and the bottom up. Strengthening the core and hips can help keep the legs and knees in a strong functional position.” When these muscles are strong, they support the legs, increase stability, improve coordination, and take pressure off knee joints.

How Hinge Health Can Help You

If you have joint or muscle pain that makes it hard to move, you can get the relief you’ve been looking for with Hinge Health’s online exercise therapy program.

The best part: You don’t have to leave your home because our program is digital. That means you can easily get the care you need through our app, when and where it works for you.

Through our program, you’ll have access to therapeutic exercises and stretches for your condition. Additionally, you’ll have a personal care team to guide, support, and tailor our program to you.

See if you qualify for Hinge Health and confirm free coverage through your employer or benefit plan here.

This article and its contents are provided for educational and informational purposes only and do not constitute medical advice or professional services specific to you or your medical condition.

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References 

  1. ACL Tear. (2023, August 2). Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/16576-acl-tear

  2. ACL Injury. (2022, December 1). Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/acl-injury/symptoms-causes/syc-20350738

  3. Evans, J., Mabrouk, A., & Nielson, J.I. (2023, November 17). Anterior Cruciate Ligament Knee Injury. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK499848/

  4. Filbay, S.R. & Grindem, H. (2019, February). Evidence-based recommendations for the management of anterior cruciate ligament (ACL) rupture. Best Practice & Research: Clinical Rheumatology. 33(1), 33-47. doi:10.1016/j.berh.2019.01.018

  5. Frobell, R.B., Roos, H.P., Roos, E.M., Roemer, F.W., Ranstam, J., & Lohmander, L.S. (2013, January 24). Treatment for acute anterior cruciate ligament tear: five year outcome of randomised trial. BMJ, 346, f232. doi:10.1016/j.berh.2019.01.018

  6. Saueressig, T., Braun, T., Steglich, N., Diemer, F., Zebisch, J., Herbst, M., Zinser, W., Owen, P.J., and Belavy, D.L. (2022, November). Primary surgery versus primary rehabilitation for treating anterior cruciate ligament injuries: a living systematic review and meta-analysis. British Journal of Sports Medicine, 56(21), 1241-1251. doi:10.1136/bjsports-2021-105359

  7. Knee Injury Prevention: Exercises to Keep You from Getting Sideline. (2018, August 31). JOSPT Perspectives for Patients. Journal of Orthopaedic & Sports Physical Therapy, 48(9), 734-734. doi:10.2519/jospt.2018.0509

Table of Contents
What Is the Anterior Cruciate Ligament?What Is an ACL Injury?ACL Injury SymptomsACL Injuries: A Hinge PerspectiveCauses of an ACL Injury Treatment Options for an ACL InjuryACL Surgery: What to KnowPrevention of an ACL InjuryPT Tip: Strengthen Your Core and Hips, TooHow Hinge Health Can Help YouReferences