I have a fitness app on my phone and I use the foam rolling program on the app. Usually I just follow the demonstration and don’t think much about the muscles that I am working on, mainly because most of the muscles are large muscles or muscle groups, and I can feel the soreness especially a day after workout on those muscles (the so called Delay Onset Muscle Soreness, or DOMS). However, there is this one specific muscle that I have been having a tough time finding, not to mention feeling the tension of – the tensor fascia latae muscle.
Since it’s mentioned in the foam rolling program on my phone, it must be of certain significance. But since I can’t find this muscle on my body, it triggers my curiosity and makes me want to know more about it. After reading about tensor fascia latae, or TFL muscle, in my anatomy book recently, I finally know where this muscle is in a human body and what it does – theoretically. Despite knowing the anatomy of TFL, it didn’t change the fact that this muscle was like a stranger to me, because I still couldn’t find it!!! Also, I want to know more practical examples of TFL. Therefore, I went ahead and did some research, and here’s what I found.
How to Locate Tensor Fascia Latae?
TFL is a small muscle located in the anterior lateral side of the thigh. It originates from anterior aspect of iliac crest and anterior superior iliac spine (i.e. the prominent hip bone), then inserts into the iliotibial tract, or IT band, which is a thickened lateral portion of the fascia latae. Some include TFL in the IT band so you may be already foam rolling the muscle when you are foam rolling the IT band. TFL is about 15 to 18 cm / 5.91 to 7.09 inch long, 2.1mm / 0.08 inch deep, and can be easily covered by a hand. Therefore, to locate the muscle, you can place your hand by the side of your thigh, the wrist right next to your hip bone. Your TFL is now under the cover of your hand. You can feel the movement of the muscle when you rotate your leg (foot) inward when standing or lying on your back.
Functions of Tensor Fascia Latae
TFL is a multitasker. Its primary function is to steady the leg and torso on the thigh by tightening iliotibial tract. This function is performed on your standing leg when you are walking, running, or taking stairs. When a person is standing on one leg and the pelvis drops on the opposite side, it may imply that his/her TFL on the standing leg is not working or weak, the condition known as the Trendelenburg sign.
The second function of TFL is to flex (when you lift your leg to climb a stair) and abduct (when you do side stepping) the thigh. The third function is to rotate the thigh medially (like when you move your toes inward while standing). TFL acts with other muscles in both of these functions.
What Happens When Tensor Fascia Latae is Tight?
Above we mentioned a situation when TFL is weak. What if TFL is tight or shortened? Generally, tight or shortened TFL can mean one keeps his/her thigh flexed for too long, over using the muscle, or it can be a sign of a weak prime mover, synergist or antagonist (the muscle that is in charge of, acts together or in the opposite direction in a movement). If the situation persists, it can put excessive stress on the part that TFL affects and cause pain.
Shortened TFL is one of the causes of anterior pelvic tilt (APT). Some other causes are for example weak abdominal muscles, pulling force of fetus during pregnancy. As I have mentioned in another article, APT isn’t necessarily a bad thing. But holding this position for a long time even turning it into a habit becomes a posture problem. It will put excessive stress on the back muscle and therefore cause lower back pain. Shortened TFL can be caused by a sedentary lifestyle. When a person stands, shortened TFL can pull the front of his/her pelvis, causing the pelvis to tilt forward.
Tight TFL is also associated with Greater Trochanteric Pain Syndrome (GTPS) - which affects 1.8 per 1000 patients annually, knock knees (also known as genu valgum), as well as some IT band problems.
How to Determine If Your Tensor Fascia Latae is Tight?
There are a few tests you can do at home to see if your TFL is tight:
- I found this one the easiest and most straightforward.
- Some assistance may be needed in order to perform this test.
- I call this one the Posterior Pelvic Tilt Test
- This one doesn’t need assistance but is less straightforward than Thomas Test.
If you have a positive sign for either of these tests, it’s likely that your TFL is tight.
How to Relax and Lengthen Tensor Fascia Latae?
First thing is to massage and stretch your TFL. Massaging and stretching the TFL not only relaxes the muscle, but also makes sure that no or little compensation from TFL happens in the exercises that follow. Now this is why my foam rolling program emphasizes on the TLF.
Here’s an example of how to foam roll the TFL. It’s better to use a massage ball since the TFL is a small muscle, but if it’s your first time doing this, you may want to use a foam roll instead as it’s gentler to the muscle. Stretching the TFL is very similar to stretching the quads and IT band. In fact, I think you can stretch your TFL while doing those stretches.
Next is to work on strengthening the muscle that is the root of the problem. Take the APT for example. Shortened TFL pulls the pelvis down, therefore strengthening the abs and glutes helps to antagonize that action and keeps the pelvis in its neutral position. If knock knees are not severe, strengthening the glutes also helps to alleviate the condition. Since TFL is a medial rotator in this case, gluteus maximus acts as a lateral rotator that antagonizes TFL.
Some say massaging and stretching is the short-term solution, yet I disagree. Imbalances and posture issues don’t happen in one day. They are likely caused by lifestyle and habits. If your daily job doesn’t require a lot of physical movements, you probably have a sedentary lifestyle. As long as your lifestyle continues, to counterbalance the problem, you need to keep massaging and stretching the TFL, as well as reinforcing the muscles that are the underlying problem.
Tensor Fascia Latae once may sound like a magic spell to me but not anymore. Now I know where it is, how to relax it and to prevent potential problems caused by it.
If you have the same doubt as me, I hope this article helps answer your questions. If you have other questions or disagree with the information provided, feel free to leave your comment below.
 W. Larry Kenney, Jack H. Wilmore, David L. Costill. Physiology of Sports and Exercise. Six Edition.
 See .
 Eric Wong. 3 Steps to Eliminating Tensor Fascia Latae Pain & Tightness.
 Greater Trochanteric Pain Syndrome. Physiopedia.