Iliotibial band syndrome (ITBS), often shortened to IT band syndrome, is one of the most common running injuries. It causes pain on the outer side of the knee that comes on while running and can make it hard to bend your leg. The good news: by adjusting your training load and strengthening your hips, it heals well in the vast majority of cases.
The short answer
- IT band syndrome causes pain on the outside of the knee, often after a set number of kilometres or when running downhill.
- Rather than friction, it seems to be compression of a richly innervated tissue lying under the iliotibial band.
- Treatment starts with load management: cut volume and downhill running, without necessarily stopping all exercise.
- Strengthening the glutes and hip abductors is the best-supported exercise approach.
- If the pain lasts more than a few weeks, see a physiotherapist or sports doctor.
Contents
I got this injury after my first marathon. No pain during the race, but as soon as I crossed the finish line I felt pain on the outside of my knee. A few hours later, simply bending or straightening my leg was extremely painful. Let’s look at where this injury comes from and how to treat it.
What is iliotibial band syndrome?
The iliotibial band is a wide band of fibrous tissue running down the outside of the thigh. At the top, it is connected to the tensor fasciae latae muscle (TFL) and the gluteus maximus. At the bottom, it attaches to the top of the tibia after passing over the outside of the knee.
The pain has long been explained by the band rubbing over a bony bump on the femur (the lateral epicondyle) each time the knee bends, hence the “friction syndrome” label. That explanation is now being questioned. Anatomical studies have shown that the band is firmly anchored to the femur and does not really “slide” back and forth. The pain is more likely due to compression of a richly innervated layer of fat and connective tissue just beneath the band, at around 30 degrees of knee flexion (Fairclough et al., 2006).
This detail matters in practice: it is not a tendon “wearing out”, but an area that does not tolerate repeated compression. What counts is to reduce that stress for a while, then make your body better able to handle it.
How to recognise it
The pain is located on the outer side of the knee, slightly above the joint. It often starts after a fairly constant time or distance, then builds until you have to stop. Downhills and stairs easily bring it on. It usually settles at rest. Only a health professional can confirm the diagnosis, as other knee problems can feel similar.
What causes IT band syndrome?
Like most running injuries, it is first a question of load. A sudden jump in mileage, a run much longer than usual or a race with a lot of downhill are classic triggers. To avoid these spikes, it helps to track your training load week by week.
On the biomechanics side, a systematic review found a tendency towards greater hip adduction (the thigh moving inwards) and more knee internal rotation in affected runners. The authors stress, however, that the evidence is limited and based on few studies (Aderem and Louw, 2015). Another study observed that runners with the syndrome had weaker hip abductors on the painful side (Fredericson et al., 2000).
When I got injured, I had run the marathon in light racing shoes I used for competitions: the Asics DS Racer. They have a slight pronation control, while my foot strike is neutral. Long distance plus a not-quite-suitable shoe: that combination was enough. Unless you have a specific condition, choose models that do not alter the way you run too much, and avoid switching shoes abruptly before a long race.
How to treat IT band syndrome
As soon as the pain starts, I encourage you to see a sports doctor or physiotherapist for medical advice. Personally, I also see an osteopath whenever I have pain. That time, he noticed my ankle was stiff. Even if the pain is at the knee, it is worth looking at the whole chain: ankle, knee and pelvis work together.
Keep in mind that treatments for ITBS have been little studied in good-quality trials (Ellis et al., 2007). The advice below is therefore based on the best available evidence and clinical experience, not on certainties.
Adapt your running rather than stopping completely
Total rest is not always necessary. The idea is to reduce what triggers the pain: volume, long runs and especially downhills. Some running physiotherapists even suggest keeping your interval sessions, walking the recoveries if needed and sharply cutting volume. Running a bit faster changes the knee angle and may be better tolerated than slow jogging.
For easy endurance running, you can replace some of your running with an activity that does not hurt: swimming, deep-water running or, for some, cycling. A simple rule of thumb: mild pain that is gone the next day is acceptable; pain that increases during the session or the next day means you need to back off.
Strengthen your glutes and hip abductors
This is the best-supported approach. In Fredericson’s study, runners followed six weeks of hip abductor strengthening: their strength improved and most of them were able to return to running pain-free (Fredericson et al., 2000). The study had no control group, so be cautious about the size of the effect, but it has shaped current management.
In practice, do exercises such as side-lying hip abduction, single-leg glute bridges, banded lateral walks or controlled step-downs two to three times a week. Increase the difficulty gradually.
To come back with a plan that accounts for your training load and includes strength sessions, you can try RunMotion Coach free for 7 days.
Stretching, foam rolling and massage: relief, not a cure
Many runners stretch their IT band. Yet this band is extremely stiff: a stretch or foam roller is unlikely to really “lengthen” it (Falvey et al., 2010). Stretching the glutes and TFL, or massaging the thigh, may still feel relaxing. Do it if it helps, but don’t count on it to fix the problem.
Ice and anti-inflammatories
Applying cold for about ten minutes can calm the pain in the days after a flare-up. A handy trick is to use a bag of frozen peas to wrap the outside of the knee (don’t eat them afterwards if they have been frozen and thawed several times). When I was injured, I also tried Pressurice, a cooling compression wrap, which was very practical.
Bear in mind that ice mainly relieves pain: its effect on healing has not been shown. Recent recommendations also advise avoiding anti-inflammatory drugs without medical advice and favouring a gradual return to activity (Dubois and Esculier, 2020).
How to return to running after IT band syndrome
Start with 20 to 30 minute easy runs on flat, even surfaces, then gradually increase the duration. Bring back downhills and long runs last, as they load the area the most. Our return-to-running programmes give you a concrete progression. And to avoid a relapse, read our article on how to prevent running injuries.
If the pain persists despite a few weeks of adjustments, or comes with swelling or the knee locking, see a health professional.
FAQ: IT band syndrome
How long does IT band syndrome last?
It depends on how long you have had the pain and how quickly you adjust your load. Caught early, it often improves within a few weeks. If it has been there a long time, it can take several months.
Can you run with IT band syndrome?
Often yes, by reducing volume and downhills. Mild pain that is gone the next day is acceptable. If it increases during the run or the next day, cut back further.
Should you stretch your IT band?
Stretching may bring relief, but the band is very stiff and unlikely to really lengthen. Strengthening the glutes and hip abductors is more useful.
What is the difference between IT band syndrome and patellofemoral pain?
IT band syndrome hurts on the outside of the knee. Patellofemoral pain is felt at the front, around or behind the kneecap. A health professional can tell them apart.
Hang in there! With patience and strength work, most runners make a good comeback. To start again with a tailored plan that builds your load gradually, try RunMotion Coach free for 7 days.
Updated on 30 October 2026.
Sources: Fairclough et al., J Anat, 2006 · Fredericson et al., Clin J Sport Med, 2000 · Aderem and Louw, BMC Musculoskelet Disord, 2015 · Falvey et al., Scand J Med Sci Sports, 2010 · Ellis et al., Man Ther, 2007 · Dubois and Esculier, Br J Sports Med, 2020.
