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Beginner's Guide to Knee Pain


Knee pain is one the most common reasons for athletes to seek out physician assistance. “It can be caused by both overuse and trauma, which is what athletes do to their knees almost every day," says Jennifer Lewis, PT, ATC, a performance physical therapist at Athletes’ Performance. Structural abnormalities can make the problem worse.

How It Happens

The knee is an intricate joint consisting of multiple structures that have to distribute forces from the ground up through the body, as well as from the upper body down through the leg. As a result, there are many different reasons and causes of knee pain, and the pain can be in several different places throughout the knee.

Most knee pain results not because the knee itself, but from some other part of the body, Lewis explains. For instance, a tight iliotibial band, hip flexors, or quadriceps muscles, dominant hamstrings or quads, or weak hip rotators can all contribute to excessive stress and strain being transfered to your knees. Also, if your core is unstable, your body will try to gain that stability somewhere else—often times at the knees.


Where Does It Hurt?

Front of the knee

  1. Above the knee - pain from quadriceps muscle strain and quad tendon inflammation, often from activities where the knees come past the toes, as with poor squatting technique.
  2. Below the kneecap - the source of pain is the patellar tendon, which connects the knee cap to the top of the lower leg.
  3. Under the knee cap - pain from excessive compression of the knee cap and from arthritic changes underneath the knee cap.

Back of the knee

  1. Pain can be to the inside, middle, or outside, often due to hamstring or calf muscle tendon involvement or poor joint mobility, especially when bending the knee.

Inside of the knee

  1. Pain can be due to tendinitis from the groin muscles and where the tendon inserts. It also can be due to ligament strain of the medial collateral ligament (MCL) or irritation to the medial (inside) meniscus.

Outside of the knee 

  1. Pain can be due to tendinitis, often from a tight iliotibial (IT) band. It also can be due to ligament strain of the LCL or irritation of the lateral (outside) meniscus.

By the Numbers

Number of menisci that act as shock absorbers within the knee and help distribute forces evenly throughout the knee joint.

Number of major ligaments that support the knee joint (two are inside the joint capsule (ACL and PCL) and two are outside the joint capsule (MCL and LCL)

Number of muscles that cross the knee joint and attach above and below it.

Who’s At Risk

Endurance athletes (runners, cyclists), explosive athletes (basketball players, cyclists, skiers), and anyone who participates in repetitive, movement-based activities is at risk. In addition, adolescents, females and taller people may be more susceptible to knee pain, as well as people who have poor strength and neuromuscular control through their glute muscles.


  • Intense pain, inflammation, or bruising at the site of the injury
  • Pain when walking or getting up and down, and with stairs
  • Reduced and/or painful range of motion
  • Feeling of locking, catching, giving out or buckling with weight-bearing

Initial Treatment

  • Apply ice applications for 15-20 minutes, 3-4 times a day.
  • Aspirin, acetaminophen, ibuprofen and naproxen may relieve pain and reduce inflammation.
  • Compress the knee joint with an elastic wrap if inflammation and swelling are present.
  • Use a pillow to elevate the knee while at rest and during the night.
  • Rest until symptoms diminish, which could take several days or several weeks.
  • See a doctor if the pain is severe or if the pain persists for two weeks.


Comeback Strategy

Gradually increase the intensity, duration, and frequency of training. Coming back too early might force you to compensate for the injury by changing the way you move or the technique necessary to perform well in your sport. So go through all the movements required in your sport without pain before returning to action. And apply ice packs for 15-20 minutes after an exercise session.


Incorporate these prehab exercises into your comeback workouts:

  1. Side-Lying Abduction
  2. Side-Lying Adduction
  3. Glute Bridge
  4. Glute Bridge - 1 Leg
  5. Face-down, Glute Activation With Knee Flexion (for quad lengthening)
  6. 1/2 Kneeling Hip Flexor Stretch

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How to Avoid This Injury

Do not increase the intensity, frequency, or duration of your exercise routine more than 10 percent each week. Wear pads or other protective devices (braces, wraps) to cushion blows taken in volleyball and basketball, and protect the knees.

Movement Prep

Incorporate these movement prep exercises into your warm-up routine:

  1. Mini Band Walking - Forward, Bent Knees
  2. Mini Band Walking - Lateral, Bent Knees
  3. Mini Band Walking - Forward, Straight Leg
  4. Mini Band Walking - Lateral, Straight Leg
  5. Lateral Squat
  6. Knee Hug - In Place
  7. Leg Cradle
  8. Bounding - Forward (focus on "sticking" the landing to improve single-leg stability)
  9. Bounding - Lateral (focus on "sticking" the landing to improve single-leg stability)

Jim Brown, Ph.D. has written 14 books on health, medicine, and sports. His articles have appeared in the Washington Post, New York Post, Sports Illustrated for Women and Better Homes & Gardens. He also writes for the Duke School of Medicine, UCLA School of Medicine, Cleveland Clinic and Steadman-Hawkins Research Foundation.

Training Progam: Decrease Pain and Tightness

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Tags: Knee, Injury Prevention, Triathlon, Regeneration, Injury, Prehab, Skiing, Knee Pain, Rehabilitation, Snowboarding


  1. Jennifer Lewis, PT, ATC, Performance Physical Therapist, Athletes’ Performance, Phoenix, Arizona
  2. American Physical Therapy Association
  3. eMedicine.com
  4. MayoClinic.com
  5. National Guideline Clearinghouse