A veteran client returned to me for the first time in a few years with right hip pain. Upon her return, her stated goals included getting instruction for “strength exercises to alleviate pain.” Seems like a reasonable request, right?
However, she’s a busy pediatrician who is married and has two kids of her own. She runs very early in the morning to allow time for all this. An important role of the sports-medicine clinician is to recognize the conundrum of “unlimited wants, limited resources.” Where in her busy schedule can she devote even more time and energy for additional exercise?
My favorite saying is, “The best exercise is living well.” That is, how we position and move our bodies plays the biggest role in how we feel. In running, this refers to stride efficiency, which plays the biggest role in our:
- Speed — Both our top speed and top endurance;
- Feelings — The relative ease and comfort of running; and
- Recovery — How quickly we rebound from training and racing.
Beyond that, stride efficiency also directly impacts our:
In other words, if you position and move efficiently, then running can actually improve mobility and strength without any supplemental exercise input! Most runners have, at some point, experienced the phenomenon where the more they run, the more mobile and strong they feel.
But the converse must also be true, that inefficient posture and movement may facilitate stiffness and weakness. I see this consistently in the clinic. My manual therapy and the client’s stretching improve mobility, yet that motion regresses after only a few runs. And consistent strength training fails to yield improvement in strength measurements or functional tests.
How do some runners, who perform copious mobility and strength work each day, continue to struggle with pain, injury, or performance issues, while other runners do next to no exercise besides running and thrive? Could the prime variable be efficiency?
In stubborn pain cases, only when we evaluate efficiency, do we see improvements in mobility, strength, and pain relief. Additionally, when we optimize efficiency and apply strength, we see gains in both injury prevention and performance. Thus, efficiency may be the true source of living well.
This begs the questions:
- What is efficiency and how does it help or harm our running?
- How do we find efficiency?
- What role should strength and mobility inputs have in our athletic routine?
Introducing the Efficiency Equation: Efficiency x Load = Fitness
Just as some runners can do little “prehab” activity, stay healthy, and run fast, so too, are runners who are seemingly able to round into shape quickly and perform at a high level off of minimal training. Yet there are others who undertake consistently large volumes of training and racing, yet can’t seem to progress fitness and performance. Why?
While admittedly a loaded question with many possible variables, basic efficiency plays a huge role in the ability to build fitness and perform:
- Posture efficiency creates automatic core stabilization, creating a strong base of support.
- Fully mobile arms and legs moving with minimal resistance generate maximal propulsion for long durations.
But what about the converse?
- Inefficient posture fails to keep a trunk stable and creates energy-absorbing hinge points.
- Inefficient limbs exert excessive strain on other parts of the body, including the trunk, and can absorb excess energy.
A Tale of Two Runners (and how the Rich Get Richer and the Poor Get Poorer)
Take two runners, each running 10 miles per day at the same pace. Runner A has efficient posture and mobile, efficient limbs. Runner B has inefficient posture (say, excessive trunk extension) and as a result over-strides.
Runner A is far more likely to:
- Run faster with less energy;
- Have minimal spine or leg pain;
- Recover faster because they use less energy and absorb less landing forces; and
- Improve their training capacity, endurance, and top-end speed faster.
The efficiency variable of our equation isn’t simply the continuum difference between fast and less fast. Efficiency is a determinant of:
- Fast versus slow,
- Pain-free versus painful,
- Mobile versus stiff,
- Strong versus weak, and
- Healthy versus unhealthy.
In these cases, the efficient Runner A gets fitter, stronger, and more mobile. The inefficient Runner B does not. Runner B has to exert increasing amounts of energy and effort to keep up with Runner A. And if they fail to give up this pursuit, more often than not, they become injured in the process.
Mathematics and the Efficiency Variable
If we apply basic mathematics to running fitness, “Efficiency” represents a positive number ranging from greater than 0 to above 1.
Good Efficiency x Load = ↑Fitness
“Good Efficiency” has a value greater than 1.
As with Runner A above, a positive efficiency variable becomes a multiplier of load. Applied mileage, speedwork, long runs, and strength work on an efficient system create positive adaptations through minimal stress absorption, fast recovery, and physiological growth.
Okay Efficiency x Load = ↔ Fitness
If a runner has “Okay Efficiency,” the value is close to or equal to 1.
This represents a runner who is plateauing in either performance or health, often in a cycle of small aches, pains, and injury (“The Whack-a-Mole”). They often can only run a certain amount before succumbing to pain. This is also the runner who does copious amounts of mobility, strength training, or side endeavors like exercise classes, cross training, or yoga yet fails to experience significant improvement in mobility, strength, pain relief, or performance.
Poor Efficiency x Load ↓Fitness
In rare cases, in a runner with “Poor Efficiency,” the value is less than 1.
If efficiency is poor enough, any amount of activity is so stressful that fitness decreases with load application. These are the runners who get stuck in an injury cycle that includes frequent bouts of complete rest followed by flare-ups when they try to resume. Significant inefficiency means that the load application immediately targets sensitive areas and creates tissue strain. With efficiency this poor, it is common to have increased pain with smaller and smaller loads (“The Sinking Ship”).
Efficiency © x Load = ↑Fitness
We all know that runner with terrible running form who somehow fails to get injured and even performs well. Aren’t these runners defying the efficiency mathematics? Enter the Callous Coefficient (©).
A marvel of human anatomy and physiology is adaptive conditioning. Even under the most stressful stimuli, the body is capable of forming protective callouses. These can be literal, such as on the bottoms of the feet and toes, or metaphorical, where the joints of the legs and spine develop a higher capacity of absorbing detrimental stressors.
These callouses are protective of inefficient loading, to a point. But like a dam failure, once they give out, any protective quality to efficiency is also gone. This explains why many runners with bad form are just fine for many years until they hit that tipping point. The resulting rest erodes the protective callous, leaving those quirky-striding runners with their true inefficiency, and with it a failure to tolerate previous training loads.
Three Steps to Finding and Reinforcing Efficient Running
Now what? How do we find, maintain, and reinforce efficiency? And how do we increase our fitness on the basis of the efficiency variable?
Step #1: Find Efficiency.
In human biology, structure dictates function. Starting at the tiniest proteins, up to the largest bones and organs, the shape and make-up of our parts dictates how the body performs. The alignment and stacking of body segments, both large and small, dictate their functional interactions.
The alignment of body segments allows for:
- Force and energy transfer through our body with the least amount of resistance or energy absorption (strain) as well as maximal propulsion.
- Full and efficient neuromuscular activation of both core stability and propulsive muscles in our trunk and limbs.
Posture provides the stable base upon which efficient motion is derived. Without efficient posture:
- Energy concentrates in stress points, which can cause pain and injury.
- Propulsive energy is lost because it fails to generate or is mal-absorbed in the body.
The two primary posture and alignment variables are:
- Trunk alignment — Neutral, balanced stacking and angling of body segments.
- Hip hinge — Promoting both hip utilization and forward engagement for running.
Once efficient posture is established, efficient movement of body segments is the next step.
For the lower body, this includes:
And for the upper body, we mean shoulder-blade-mediated arm swing.
Where does the rubber meet the road? The end product of efficient alignment and limb motion is a footstrike that lands:
- Nearly beneath the body’s center of mass with a shin bone that is vertical to the ground.
- Outside-to-inside, finishing with medial foot arch and big toe push-off.
Step #2: Use Mobility to Enhance Efficiency.
Once you are aware of ideal posture and motion, can you do it? If you cannot, this likely means parts of your body lack the mobility to get into or maintain the position.
Our performance-mobility series was established to help runners self-assess isolated motions and restore alignment and optimal joint motion. So, if you cannot, say, maintain a neutral trunk without a rounded upper back and shoulders, or if your hips are too stiff to generate good hip mobility, then you need to apply mobility exercise to restore this motion.
Step #3: Apply Loads Progressively.
Once efficiency has been established, it’s time to add load. Basic running is the primary load application, but this can also include specific types of running, including speedwork, uphill and downhill running, and training on specific terrain. Besides running, load application may also include various strength exercises.
At this point, I hope the primary goal is clear: we are training ourselves to maintain efficiency over as many varied and specific challenges as possible. In this case, load application generates true fitness only when efficiency can be maintained under those loads.
The Runner’s Efficiency Cycle
Distilled to the essentials, an efficient runner flows continuously through the efficiency cycle:
What does efficient look like?
What do elite runners look like? What about your fastest friends? Having a strong visual image of efficiency is our starting point.
Find it and feel it.
“Look Fast and Feel Fast,” all the time, even when you’re running slow.
Work into it.
If finding and maintaining efficiency is difficult, then it’s time to go to work with targeted mobility strategies (that often include things beyond stretching like spinal and soft-tissue mobilization).
Commit to it.
Once you know what your best version of efficiency looks and feels like, commit to it. Run that way all the time, or for as long and as frequently as you can. Stride optimization isn’t easy, but we work on form with every other athletic pursuit. Commit to excellence. This often requires running a little slower in order to maintain efficient alignment and motion.
Reinforce it with strength training.
The true benefit of strength training is its reinforcement of efficient positions and movements. Beyond various run workouts, reinforce run-specific postures and motions using:
- Ground exercises (including abdominal activation, hip flexors, and push-off)
- Standing exercises (hip hinge and trunk stability)
- Dynamic exercises (hip mobility, balance, and running drills)
Efficiency is dynamic and sensitive to other inputs, so reassessment through consistent check-ins is key. Besides the basic feedback that may come from a video or picture, your body will provide many metrics of intrinsic feedback. These include:
- Aches and pains
- Ease of running
Reductions in any of these variables (with consistent loading, that cannot be explained by other factors) often indicates that efficiency has decreased.
Efficiency-focused load application creates sustainable fitness development without compromising joint and tissue health or overburdening the body’s ability to absorb stress and quickly and completely recover. This is why:
- The fastest runners are most efficient;
- The runners with the most longevity are efficient; and
- The happiest runners are efficient.
Thus, when there’s any question about what you can do to improve your running, start with efficiency. “Living well” gets you the best possible outcomes for the least amount of time and effort.
Call for Comments
- Have you experienced the phenomenon where efficiency seems to amplify your running?
- And how about the opposite, do you have an inefficient element of your running stride that gets in the way of improving your fitness?