3 Reasons You Have Knee Pain From the Leg Press

A leg-press machine can be a great tool for building strong quads and glutes, but you may experience knee pain after using it.

Pain during or immediately after exercise is cause for concern. Find out why your knees hurt after you use a leg press so you can prevent and treat any potential injuries. It could be because of an injury, issues with how you do your leg presses, or the amount of weight you're using.

1. Knee Injury

"During the phase of the leg press that involves deep knee flexion, the stress goes to the posterior aspect of the knee, or back of the knee, and the bones and cartilage in the back of the knee," says David Geier, MD, an orthopedic surgeon and sports medicine specialist in Charleston, South Carolina.

Pain in that area could be the result of cartilage damage or structural damage, such as a torn meniscus, Dr. Geier says.

"Applying a large amount of stress to that part of the knee [also] can cause pain in someone with early arthritis or other injuries," he says.

• Swelling
• Inability to bear weight on your knee
• Fever, plus swelling and redness
• Inability to extend or flex your knee
• Physical abnormality in your knee or leg

2. Improper Exercise Form

If you feel knee discomfort on the leg press machine, you might be doing it with improper technique. This may lead to strain or injury.

1. Start seated with your back flat against the machine's back rest.
2. Place your feet flat on the resistance plate about shoulder-width apart, with your knees bent at about 90 degrees.
3. Hold the handles, avoiding movement in your lower back.
4. Exhale and push the plate away from you with your feet until your legs are straight, avoiding locking your knees.
5. Pause for a second.
6. Slowly bend your knees to return to the starting position.
7. Repeat.

3. Too Much Weight

You can put undue strain on your muscles and joints by trying to lift weights that are too heavy.

“If you do have knee pain from a prior injury or just wear and tear from years of being active, consider not going as deep with the exercise,” he says.

Alternatives and Safety Precautions

“Generally speaking, the leg press is safer than many other knee exercises, especially leg extensions,” says Geier, adding that this is partially because your feet stay planted on the plate of the machine.

Squats may be a safe alternative, as they also require you keep your feet planted on a fixed surface.

“This allows for both your quads and hamstrings to contract, protecting the knee during the motion,” Geier says.

Squats, however, will work your glutes and hamstrings more than a seated leg press.

Some leg-press alternatives:

• Lunges
• Deadlifts
• Rear-foot elevated split squats
• Wall sits
• Step-ups
• Cardio machines

If you have severe or constant knee pain, ask your doctor or physical therapist what options may be best for you.

The Takeaway

• Common reasons your knee may hurt after a leg-press session include injury, improper technique, or weights that are too heavy.
• Alternative exercises, as well as knee sleeves and wraps, may help you address light to moderate pain without making it worse.
• Contact your doctor if your knee pain gets worse or does not go away, or if it accompanies redness and swelling, an inability to bear weight, or a fever.

Additional reporting by Sarah Klein.