Performance Mobility, Part 1: Introduction And Hip Flexion and Extension Mobility

Joe Uhan introduces a performance-mobility series and discusses hip flexion and extension mobility for endurance running.

By on January 10, 2017 | Comments

Stay the Course

[Author’s Note: This is Part 1 in a six-part series on functional mobility self-assessment and restoration for runners. See also Part 2 on trunk rotational mobility, Part 3 on foot and ankle mobility, Part 4 on knee mobility, Part 5 on trunk extension, and Part 6 on hip abduction and rotation mobility.]

Happy New Year! Here’s to another year of running far and–if we can help it–relatively fast.

Running itself seldom requires enhanced motivation or resolve. However, to consistently perform the ancillary tasks–stretching, strength, and other concepts we know can improve our running–is often as difficult as the toughest New Year’s resolutions out there.

What’s worse, it’s difficult for runners to know what exactly to do and why. Strength training is great, but there’s a lot of stuff out there. The same for stretching, although for most runners it tends to be even less enjoyable and may even come at a cost. A scientific-literature search of “stretching and running” yields a depressingly opaque palette of data. Some studies show benefit while others show outright detriment via loss of speed, power, and tendency toward more injury! (The nerve!) Thus, more often than not, the individual runner’s consensus is ‘the null approach.’ That is, do nothing and hope for the best.

However, before swearing off stretching forever, allow me to present a new concept, something I call performance mobility. Simply, what mobility do we each need to run in a consistently strong and efficient way? And then, how do we best (with unlimited wants and limited resources) develop and maintain it?

“Stretch What You Need To:” Performance Mobility Defined

Ask any successful veteran runner about the key to sustainability, and what they’ll tell you (explicitly with words, or implicitly with results) is consistency: doing the same thing (in a philosophical sense), day to day and year to year. Consistency breeds fluidity, more output for less effort, and sustained momentum–the axioms of endurance success. Implicit with consistency isn’t just X miles at Y pace Z times a week. It is also how you run: how the body moves, arms and legs, hips and shoulders, one foot in front of the other. Consistent performers have consistent body language.

Consistency is king and so, therefore, is consistent mobility.

As a medical professional, runners constantly ask, “What should I stretch?” Here has been the evolution of my answer over the years:

  • Early years: “I don’t know!” This was based on the equivocal, confounding literature on stretching.
  • Middle years: “Stretch what you need to stretch!” Only half tongue in cheek, this notion was based on treating individual runners: through clinical experience, determining mobility needs for specific running issues. In doing this work, consistent patterns began to emerge.
  • Today: “How are your ‘mobility metrics?’”

‘Mobility metrics’ are self-assessment tools for determining if we have the mobility necessary to run efficiently. They cover body systems that, like running, are whole body:

  • Feet and ankles
  • Knees
  • Hips
  • Spine
  • Shoulders

For each body group, there is a running-specific mobility test. In performing each metric, runners should ask themselves:

  • Do I have full mobility?
  • Is the mobility equal on both sides of my body?

These measures of performance mobility represent my best estimate of the foundational mobility required for high-efficiency, peak-performance running. From there, what happens next is simple. Got the mobility? You’re good to go. Coming up short? Get to work! Suddenly, stretching is no longer a burdensome chore. Instead, it’s as important to training and racing as putting on running shoes. Moreover, deficits of performance mobility will be instructive: range-of-motion loss is often a sign of stride inefficiency, especially when mobility loss is asymmetrical.

In 2017, we will outline five mobility metrics: what they are, what they mean to your running (why they are vital for peak performance and problem prevention), and how to maximize and maintain them. In doing so, our goal is to help you develop performance mobility as an important tool for efficient, joyful, and sustainable running.

[Author’s Note: This article is Part 1 of this five-part series on performance mobility. Part 2 and Part 3 have now also been published.]

The Hip Flexion and Extension Mobility Metric

The hips are everything in running–the true powertrain of the stride. How well our hips move can provide the best information on stride integrity. If the hips lose motion (and, in turn, strength), overuse injuries can quickly occur, above or below. As such, having full and equal hip flexion and extension motion is crucial for both top speed and injury prevention.

Details: Lie flat on the floor, hug your knee to your chest/armpit.


  • Be able to touch thigh to ribcage
  • Opposite (straight) leg should stay complete flat (and slightly lateral)

Common Deficits:

  • Inability of thigh to touch ribs (hip/pelvic flexion loss)
  • Straight leg either flexes or adducts (‘drags in’)


Range-of-motion loss at the hip causes relative overuse above and below. But what is worse is when one half of the pattern–one leg flexed and the other flat–is significantly stiffer than the other. This sort of asymmetry is the primary driver of most lower-leg (knee, shin, ankle, foot) injuries, as well as chronic low-back and pelvic pain.

Single Knee Chest

Joe Uhan performs the single-knee-to-chest test for hip mobility.

Restorative Mobility Exercises for the Hip

If you self-assessed and found some flexion and extension stiffness, it’s time to fix it! Below are some stretches to improve your hip mobility.

Upward-Facing Dog and Child’s Poses

To enact these borrowed poses from yoga, first press up and gently drag your body forward into Upward-Facing Dog Pose. Then carefully shift back on your knees and bow into Child’s Pose. These actions provide a stretch to elements of the spine, pelvis, and hips. Perform 5 to 10 times, as needed.

Upward Dog - Side

Upward-Facing Dog Pose.

Child's Pose - Side

Child’s Pose.

Runner’s Lunge

This stretch should be in every runner’s playbook. All it takes is a chair, a couple stairs, a bench, rock, tree stump… you get it. Place a foot onto such object, then drop your hands to the inside of your front knee. Then carefully place your trailing (straight) leg behind, and laterally. Your trail foot should point straight ahead. This is a key hip-flexor muscle and pelvic-joint stretch. Perform 3 to 5 repetitions of 10- to 30-second holds, per side.

Split Hip - Side

Runner’s Lunge viewed from the side.

Runner's Lunge - Rear

Runner’s Lunge viewed from the rear.

Side Lunge

This stretch helps free up the hips from the side. Assume a wide stance, then gently straighten one leg. Apply a gentle force to the straight leg with your hand on top of the thigh to feel a stretch in the straight-leg groin. This helps stretch the adductors, and elements of the hip and pelvis. Perform 3 to 5 repetitions of 5- to 30-second holds, per side.

Side Lunge - Side

Side Lunge.

Single-Knee-to-Chest Stretch

I put this one last for a reason: it will be easier after performing the previous three stretches. Using both hands, flex your knee toward your armpit. To enhance mobility, perform a “contract-relax” action by pushing away with the knee, resisting with the arms, for three seconds, then relaxing and “taking up the slack”, closer to the ribs. Perform 5-10 contract-relax stretches per side.

In subsequent columns we will outline the other mobility metrics, but the hips are where it all begins. Get them moving to kick start your new year of running!

Single Knee Chest - Top

The Single-Knee-to-Chest Stretch viewed from the top.

Single Knee Chest - Side

The Single-Knee-to-Chest Stretch viewed from the side.

Call for Comments (from Meghan)

  • Did you pass Joe’s test for hip flexion and extension mobility on both sides of your body?
  • What kind of flexibility training or stretching do you engage in, if any? Do you find that it helps you in specific ways? If so, can you describe them?
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Joe Uhan

Joe Uhan is a physical therapist, coach, and ultrarunner in Auburn, California. He is a Minnesota native and has been a competitive runner for over 20 years. He has a Master’s Degree in Kinesiology, a Doctorate in Physical Therapy, and is a USATF Level II Certified Coach. Joe ran his first ultra at Autumn Leaves 50 Mile in October 2010, was 4th place at the 2015 USATF 100k Trail Championships (and 3rd in 2012), second at the 2014 Waldo 100k, and finished M9 at the 2012 Western States 100. Joe owns and operates Uhan Performance Physiotherapy in Eugene, Oregon, and offers online coaching and running analysis at