Hip Extension: Mobility & Flexibility

Hip Extension: Mobility and Flexibility

Written by Stacy Ciarleglio, a licensed athletic trainer and ultra runner. 

In the last newsletter, I started talking about the complex joint of the hip. I introduced the fact that there has to be a balance between stability and mobility in order for the hip to function optimally. Today the focus is going to be on mobility, specifically in the motion of hip extension (an increase in the angle of the front of the hip). 

During running, the hip functions like a sling shot. The body is propelled forward by a push off mechanism that involves hip extension. As the hip is in an extended position, it is storing elastic energy in the muscles in the front of the hip (hip flexors). After the gluteus maximus muscle contracts to create a powerful push off in hip extension, the hip uses the stored energy of the hip flexors to coil back up (flex), and repeat the process. For this whole process to take place properly and without compensation there must be enough mobility in hip extension.

 When looking at hip mobility, there are three things to take into consideration. First, do the bones move properly within the joint space? Second, is the muscle flexible and long enough to allow it to stretch to the necessary length needed for full joint motion? Third, are the layers of soft tissue mobile enough to glide over one another without restriction during motion?

I am going to discuss soft tissue length and soft tissue glide a little further. That’s not to say that the actual joint motion (bones moving in joint space) isn’t important. It’s extremely important and that should be the first issue addressed through your doctor. Once the bones and joint are cleared, then you can focus on the soft tissue.

Is your hip flexor long enough to allow unrestricted hip extension to occur? Try this at home (or next Wed, May 15 at 6pm at Fleet Feet….more info on this later); get into a half kneeling position with your right knee on the ground. Put your left leg in front of you so there is a 90 degree angle at the hip and knee. Your shin should be perpendicular and your thigh parallel to the ground. Place a bar (or broom stick) in back of you along your spine. It should touch your shoulder blades and top of your glutes. Push your pelvis forward (also known as a posterior pelvic tilt) so that you flatten out your lower back and it comes into contact with the stick. If you feel a stretch in the front of your right hip, you likely have limited hip extension flexibility. Switch positions and repeat the process for the left hip. 

If you felt a stretch with that test, you should work to improve hip extension tightness. Performing the kneeling hip flexor stretch, which is a similar position to the test just described minus holding a stick along your back, is a good way to help lengthen and stretch the hip flexor. Some of you might be thinking, I do that stretch all of the time, and I still have tight hip flexors. Many of us do not hold our stretches long enough to allow them to actually achieve tissue lengthening. The old rule of thumb is to hold a stretch for 20 – 30 seconds and repeat 2 – 3 times. This might be ok for muscles that are not too short that you are just looking to relax them and return them to normal length after a workout. However, current research is showing that in order to lengthen tissue that is too short, the stretch must be held for 3 – 5 minutes.

The other component of improving hip mobility is tissue glide. There are many layers of muscle, tendon, fascia, etc within the body that must move freely upon one another in order for motion to occur. If there is limited tissue glide, it will, in turn limit tissue length and overall flexibility. To work on this, get out your trusty foam roller, trigger point quadballer or ball, or Orb and start sweating! When using these tools, you want to work along the whole length of the muscle. Start just above the knee and slowly make your way up towards the hip and abdomen (one of the hip flexors muscles is located deep with the abdomen, see picture below). When you find a tender spot, spend some time on it and bend and straighten your knee. You can also rotate your hip in and out to get the tissue from different angles and work on freeing up different motions. When you incorporate hip and knee motion into your session, you will feel the tissue attempting to glide underneath your roller (or ball). Depending on how stuck your tissue is, you might sweat a little! That’s ok, this process will get more comfortable the more you do it!  

Taking the time to properly stretch (3 – 5 minute holds) and address any soft tissue mobility and glide issues can greatly increase your hip extension. Improved hip extension translates into a more powerful hip drive, better use of store elastic energy, less chance of compensation, and less chance of hip injury!