Weightlifting Knee Injuries and Pain

Knee injury in the gym
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Lower back, shoulder, and knee are the big three "injury"' joints for active people. Even the inactive will inevitably have a mild or serious injury to one or more of these joints over a lifetime. However, adding in regular weight training into your routine can improve knee strength and prevent injury. Safety is critical when weight training, because strain and injury can occur.

Weight Training and Knee Injuries

While it may seem like weight training could contribute to knee injuries, this is not the case. Lifts like deadlifts and squats do place high forces on the knee joints, but these forces are applied mostly vertically and not horizontally or rotationally (twisting). The knees cope with vertical forces much better than high-impact horizontal and twisting forces.

While weight training is generally very safe for the knees, this is dependent on whether you practice proper form and follow the correct guidelines for each move. Even so, knee injuries do occur in weight training and in the very high forces of Olympic weightlifting, and if you have an existing knee injury from another activity, inappropriate weight training exercises could make it worse.

In general, weight training is safe for the knees as long as proper form is practiced. The body is designed to manage vertical forces on the joints. However, sudden twisting movements, poor alignment, and pre-existing injuries may put you at risk for an injury.

Common Knee Injuries

In each of the knee ligament injuries below, the damage can range from a sprain to a slight tear or a complete tear in the most serious cases. Here's what you need to know.

Anterior Cruciate Ligament (ACL)

This ligament ties the femur bone of the thigh to the tibia or shin bone of the lower leg and controls excessive rotation or extension of the knee joint. Anterior means at the front. A rear (posterior) ligament is also present. ACL injuries are seen mostly in athletes. Severe damage to the ACL usually means surgical reconstruction and up to 12 months rehabilitation.

In the gym, be careful not to allow twisting knee movements under excessive load, intentionally or accidentally.

Posterior Cruciate Ligament (PCL)

The PCL connects the femur and tibia at different points to the ACL and controls any rearward motion of the tibia at the joint. The PCL is mostly injured with high-impact forces as a result of accidents and sometimes in sports activities where a sharp blow to the knee occurs.

Medial Collateral Ligament (MCL)

This ligament keeps the knee from bending too far to the inside (medially). Damaged MCLs mostly occur from an impact to the outside of the knee, or even from an accidental bodyweight force when the leg reaches an unusual angle.

Lateral Collateral Ligament (LCL)

This is the opposite ligament to the MCL. It's on the outside of the knee and controls excessive movement outward. This ligament connects the fibula (the smaller bone of the lower leg) to the femur. Similarly the LCL is injured when a force pushes the knee outward.

Cartilage Injury

Cartilage prevents bones from rubbing together and cushions impacts. The two knee menisci (meniscus single) are cartilages that cushion the inside and outside of the knee joint. Other types of cartilage protect the ends of the thigh and shin bones. When cartilage is torn or damaged, surgery with an arthroscope may be necessary. (An arthroscope is an implement that allows a surgeon to see and fix cartilage injuries with a small incision.)

Tendonitis

Aggravated and overused tendons of the knee can cause disabling knee injuries. A related injury called "iliotibial band syndrome" (ITB) causes pain to the outside of the knee, often in runners, but it can occur in any overuse situation. Rest, stretching, and a short, two-week course of anti-inflammatory medication is often recommended. Longer duration of medication usage can result in more side effects than benefits. For pain lasting longer than two weeks, consult a physical therapist. Anti-inflammatory medication is often recommended for these types of injuries.

Prevent Weight Training Knee Injuries

There are steps you can take to minimize your risk of knee injury and pain while weightlifting. If you have an existing knee injury, take the advice of your doctor or physical therapist in the first instance.

  • Avoid certain gym workouts. Gym exercises that may be best avoided are the isolation exercises like the leg extension machine, and the leg curl exercises, either standing or on a bench. Heavy loads or deep squats should mostly be avoided.
  • Deep squat with caution. On the other hand, if your knee was perfectly healthy, with accurate technique under expert supervision and gradually progressive training load, current research shows the deep squat is a great exercise to protect against lower leg injury.

Other Causes of Knee Injury

Knee injuries, especially to the knee ligaments, are exceedingly common in sporting communities. Knee injuries can result in pain, swelling, and immobility from minor to severe effect.

For weight trainers and physically active men and women, the knee joints endure a wide range of stresses and strains. For the most part, in younger years, the knee joints serve us well. However, in sports with twisting movements—such as football, basketball, hockey, and many others—ligaments that bind the complex bones of the knee joint together can be damaged, often severely.

In addition, as we age, normal wear and tear can result in osteoarthritis of the knee joints. In this condition, the cartilage that provides cushioning between bones deteriorates and causes bones to rub together resulting in pain and stiffness.

Frequently Asked Questions

Can doing squats cause knee injuries?

If you are following proper squat form, squats should not cause knee injuries or pain. In fact, squats can be a great way to strengthen your knees. If you do experience pain while doing any squat variation, speak with your primary care doctor or a sports physician.

How do you prevent knee injuries?

Prevent knee injuries and pain by stretching your leg and knee muscles, following proper form when working out and weight training, and maintaining joint flexibility. Avoid sudden lateral movements and consider wearing knee supports to keep the muscle and joint secure.

What should you do if you hurt your knees while lifting weights?

If you feel sudden knee pain while lifting weights, stop immediately. Gauge the level of pain and discomfort you're feeling. If the pain is mild, follow the PRICE method to treat the injury by protecting, resting, icing, applying compression, and elevating your knee. If pain is moderate to severe, contact your physician.

When should you see a doctor for a knee injury?

Call your doctor if your knee pain is moderate or severe, if your knee is noticeably swollen or tender, and if you are unable to bear any weight on your leg.

A Word From Verywell

Weight training, when performed correctly, is generally safe for the knees. However, if you are concerned or have experienced a prior knee injury, you should talk to your doctor before beginning a new workout routine. Working with a personal trainer can be helpful in learning the proper technique and weightlifting form.

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5 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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