Keeping knee ligaments in line: How to strengthen your knees and avoid injury

Wondering how to strengthen your knees? Whether you're training for a marathon, chasing your kids around the backyard or simply taking the stairs every day, healthy knees make it possible to stay active.

But because the knee is one of the body's largest and hardest-working joints, your knee ligaments are also some of the most commonly injured. While some knee ligament injuries happen suddenly after a fall or awkward twist, others develop over time from repetitive stress, muscle imbalances or poor movement patterns.

The good news? Learning how to strengthen knees can help improve stability, reduce your risk of injury and keep you moving with confidence.

Here's what you need to know about the ligaments of the knee, why they matter and simple ways to take care of them.

Understanding your knee ligaments

First, let’s break down your knee ligaments and how they work. Your knee is a complex joint made up of bones, cartilage, tendons, muscles and four major knee ligaments that work together to provide stability. These ligaments also allow you to bend, straighten, pivot and change direction.

The four primary ligaments of the knee include:

• Anterior cruciate ligament (ACL): Located in the center of the knee, the ACL helps control forward movement and rotational stability. It's the ligament most commonly injured during sports that involve cutting, pivoting or sudden stops.
• Posterior cruciate ligament (PCL): The PCL sits behind the ACL and prevents the shinbone from moving too far backward. PCL injuries are less common and often occur after direct trauma, such as a car accident or a hard fall onto a bent knee.
• Medial collateral ligament (MCL): Found along the inside of the knee, the MCL helps stabilize the joint against forces that push the knee inward. It's frequently injured during contact sports.
• Lateral collateral ligament (LCL): Located on the outside of the knee, the LCL provides stability against forces that push the knee outward. LCL injuries are less common but can occur with significant trauma.

Together, these knee ligaments keep the joint stable while allowing smooth movement. When one is stretched, sprained or torn, everyday activities—and especially sports—can become painful and difficult.

Common symptoms of a knee ligament injury include:

• A popping sensation at the time of injury
• Knee pain and swelling
• Difficulty bearing weight
• A feeling that the knee is unstable or "giving out"
• Reduced range of motion

Although athletes are at higher risk, anyone can injure the ligaments of the knee through a fall, awkward twist or other accident.

How to strengthen knees for healthier joints

While there's no guaranteed way to prevent every injury, building strength around the knee can improve stability and reduce stress on the ligaments. Here’s how to strengthen knees and support long-term healthy joints.

1. Focus on your hips and glutes

Strong hips and glute muscles help control how your knees move during walking, running, jumping and landing. Weakness in these muscles can allow the knees to collapse inward, increasing stress on the ACL and other knee ligaments.

Exercises that target the glutes and hips include:

• Glute bridges
• Clamshells
• Side-lying leg raises
• Lateral band walks
• Step-ups

Building strength in these muscle groups improves alignment and helps distribute force more evenly throughout the lower body.

2. Strengthen your quadriceps and hamstrings

Your thigh muscles play a major role in supporting the knee joint. The quads help control knee extension, while the hamstrings assist with bending the knee and help protect the ACL by limiting forward movement of the shinbone.

Effective strengthening exercises include:

• Bodyweight or goblet squats
• Split squats
• Romanian deadlifts
• Hamstring curls
• Wall sits

Start slowly, focusing on proper form, and gradually increase weights or resistance as your strength improves.

3. Improve balance and movement mechanics

When it comes to preventing knee ligament injuries, strength alone isn't enough. Your body also needs good balance, coordination and control.

Single-leg exercises help train the muscles that stabilize your knee during everyday activities and sports. They also improve your body's awareness of joint position, known as proprioception.

Helpful exercises include:

• Single-leg balance
• Single-leg deadlifts
• Step-downs
• Single-leg squats (as tolerated)

For athletes, learning proper jumping and landing techniques is especially important. Landing with your knees aligned over your hips and ankles instead of collapsing inward can significantly reduce stress on the ACL.

4. Don't skip recovery

Remember that rest is an essential part of getting stronger—as essential as doing the right exercises. Without adequate recovery, muscles become fatigued, making it harder to maintain proper form and increasing the risk of injury.

To support healthy knees:

• Take rest days between intense workouts.
• Increase training gradually instead of making sudden jumps in intensity.
• Stretch regularly to maintain flexibility.
• Get enough sleep to support muscle recovery.
• Replace worn-out athletic shoes when needed.

Recovery gives your muscles time to rebuild, allowing them to better support your joints during activity.

Preventing knee ligament injuries

Some injuries can't be prevented, but many happen when muscles are fatigued, movement patterns are poor or activity increases too quickly.

You can help lower your risk of knee ligament injuries by:

• Warming up before exercise
• Strength training at least two to three times per week
• Practicing proper form during sports and workouts
• Increasing mileage or training intensity gradually
• Listening to your body instead of pushing through pain
• Cross-training to avoid repetitive stress

Female athletes have a higher risk of ACL injuries than males because of differences in anatomy, hormones and movement patterns. Strength training programs that focus on jumping, landing and cutting mechanics have been shown to reduce that risk.

If you experience sudden pain, hear a pop or feel your knee become unstable after an injury, stop the activity and have your knee evaluated rather than trying to "walk it off."

Caring for your knees

Even with the best prevention strategies, injuries can still happen. If you've recently injured your knee, start by limiting activities that worsen the pain and consider using the RICE approach during the first 24 to 48 hours:

• Rest: Avoid activities that increase pain.
• Ice: Apply ice for 15 - 20 minutes several times a day.
• Compression: Use an elastic wrap or compression sleeve to help reduce swelling.
• Elevation: Raise your leg above heart level when possible.

If pain, swelling or instability continues, it's time to see a sports medicine or orthopedic specialist.

Your provider may perform a physical exam and recommend imaging, such as X-rays or an MRI, to determine whether you've injured one of the knee ligaments or another structure inside the joint.

Treatment depends on the severity of the injury and may include:

• Physical therapy
• Activity modification
• Bracing
• Anti-inflammatory medications
• Surgery for complete ligament tears or persistent instability

Many ligament sprains improve with conservative treatment, while complete tears—particularly of the ACL in active individuals—may require reconstruction surgery followed by several months of rehabilitation.

No matter your age or activity level, taking the time to learn how to strengthen knees is one of the best ways to support your long-term mobility.

By building strength throughout your legs and core, practicing good movement mechanics and allowing your body time to recover, you can help protect your knee ligaments and stay active for years to come.

Living with knee pain? Speak to a doctor today or take our knee pain quiz.